9 The Details9.1 How to test the healthiness of an ecuYou can do this it's not without complications. It’s basically the same as wiring it up though. The ecu's only real health indicator is the check engine light, or the diagnostic plug. Other than that it falls down to the performance or lack of (in the sense that you can see something isnt right) or a malfunction. There are more complex methods but those are out of reach for DIY installers.
The diagnostic plug allows you to plug in a piece of equipment which will tell you all about the ecu and how it sees the sensors which is relies on. That will tell you if it's ok. It also involves a full set up, engine, loom, sensors, the works.
You 'could' hook the ecu up to power, hook the check engine light up, and see if it pumps out codes for all the missing parts. (ref diagnostic how too).
To do this you will basically need to wire the ecu up to the loom, or a loom, or a substitute for a loom, in part. You need to hook up earth, and power, and switched power. That’s only a few wires though. Then you will need to refer to the wiring diagram with great care, and make sure your connecting the right wires up. And, run the check engine light. It's dirty, nasty, cheap, bit if the little light blinks in the way it should, chances are it's fine.
It looks a bit like this.
User: 1uze30 on oldschool.co.nzThe other method is to send the ECU to a company like Anything Electronic Ltd
http://www.anythingelectronic.co.nz/ they will tell you if it's ok. It will cost money, but they can also fix it.
If your health checking an ecu it must be for a reason, did you drop it ? Don’t panic, I've done that quite a few times and they seem to be ok with it, well to a point. It is after all a sensitive electronic device. We had one ecu on a work bench next to a bench grinder for a couple of months. It fell, was put back up at least 3 times I know off, then my mate moved it and it was left on a welding bench for about 6mths.
We expected it to be toast. It works. It’s in a hilux conversion right now running just fine, which is amazing. It was installed because the engine came without a loom or ecu, or a few other things, so it was patch up and got running so our friend could run through cert and worry about the details later. He was told to replace it asap, he later used a mega squirt (ms3).
9.2 - Looms and ECU's / Transmissions9.2.1 Looms and ECU'sThe engine will likely come from an importer, or been someone’s garage. Often the loom is untouched, not uncommon to find something missing. Don’t be put off, but a MAF is a problem they are now expensive ($150 - $250).
If engine has cut loom at the back of the cam cover don’t be put off, a cut loom is more work to terminate at the ecu, because of missing wire. The problem with a cut loom is ecu plugs. You need all of them, and the pins that go into them. You don’t really need a long tail off each pin, some length is helpful.
Its not a big deal, the wiring time isn't doubled, but it is extra hours, as much as an extra 10hrs, if you have the time and don’t mind the extra work it could be more affordable.
Don’t worry about the 'right ecu' for the engine. Except for the VVTI engines, any 1uzfe ecu can be grafted to work with any 1uzfe engine, the issue is more about having the right plugs and the time taken to transfer it. It's the pin configurations, wiring diagrams, and getting it all set up right, if is first wire up, don’t try match up / mis-matched electrics, a big ask for a beginner, for aftermarket ecu installs some of the info here could be useful.
9.2.2 TransmissionsThere is a rumour that 1uzfe ecu's which operate the automatic as well will not rev beyond 3000rpm once wired up, untrue. Possibly caused by reverse (speed) inhibitor in some ecu's.
However, I had a long email conversation with one person who was certain his installation was not rev’ing beyond 2800rpm because an inhibitor in the ecu. While at the time of writing this he has yet to tell me he’s solved it, I ended up saying to him: your car has no ecu faults, you’ve made no mistake, it will build rev’s to over 2800rpm, but under load it falls flat. If your car was in my shop I would not even consider an ecu related cause, I’d consider it a load related issue: so vacuum leak, or fuel pump fault, etc. The key point here is if you can build rev’s over the inhibition point it’s something else. It turns out the error he’d made was minor and detailed above in the FPR pin information. It was just a simple wiring mistake, not even really a mistake.
I’ve yet to encounter this fabled failure to rev, others with real experience say its real. I do believe them.There is a rumour that a stand alone ecu is out there, it was installed into the Crown Majesta (89? or is it 1990 ?), untrue I've seen it, it runs the automatic too. But if I'm wrong and you find that ecu which was paired with a separate ECU to control the transmission. grab it, grab both.
There is a rumour that "you cannot get a 1uzfe to work with a Surf Automatic", also untrue. I've done it. It's three wires, there is more information about this further in the document.
If you can physically mount the auto to a bell housing or adapter plate and have the spline sit nicely in the torque converter it can be wired up to work properly. The problem with the 1uz-fe automatics is that they are not a sliding yoke box. It is possible to convert the 1UZFE range of gearboxes to be a sliding yoke box. I don’t think it’s worth the effort. I would rather just install the 1UZFE and it’s stock gearbox and have a truck type sliding spline drive shaft made up, easier and cheaper, a bit ugly in terms of it being a heavy and expensive driveshaft, but effective and very strong.
9.3 - Working with the Loom Casings and Plugs.9.3.1 Free the loomFree the Loom as much as possible from the plastic mouldings/casings, ultimately you want to separate the loom from the engine, there is a catch. Some of the plugs on the 1uz-fe engine in-so-far-as-I know might: are not used or any other engines. Well I’ve hunted through one wreaker’s yard once searching for ISCV plug (Idle Solenoid Control Value), and didn't find anything close so, take that as you will.
Here in New Zealand we get alot of Japanese importation from the Automotive industries. We get some really great stuff imported. However by the time engines land into New Zealand, they are usually well cooked. I have yet to see a 1uz engine without a broken plug. The engines which feature in this section of the document was pretty bad for plugs, this plug below is actually burned. I'm not sure what the story is, I guess the engine it came from had a fire?
obviously, it got well baked.
9.4 Here is what most often happensThe injector plugs, because they are at the top of the motor take a pounding from ambient heat, the little clip which holds the plug firmly onto the injector breaks away, rendering the clip useless, the condition a plug which is broken could easily cause a intermittent mis-fire. There are solutions you can buy brand new plugs for about $12.50 each, [edit]$15 each trademe.co.nz (seller:nzefi). Or the 4age (20v) plugs work just fine and are pretty cheap at a wreakers they are generally not roasted either. The billet injection rails (above) are nice, make big power just fine, if I was going to force the induction on a 95 onwards motor I would ditch the cast fuel rails for the billet earlier ones they are as good as anything in the aftermarket.
9.5 Brittle from heat, covered in corrosive dustThe plug above us is an ISCV plug, its missing a chunk, don’t do this, be careful with 1uz plugs someone has tried to get the plug of its female counterpart with some sort of metal tool and because the plug is brittle (they always are) it's relieved the stress by coming to pieces instead of coming off, expect the plug to break up if you try that. Despite the fact it’s missing a chunk and no longer seals from the environment in the engine bay (which is a harsh) it is still usable, I cannot find a replacement for it.
Look at the state of this coil plug above and that’s not the worse one, the other plug was hollow, again, 4age (20v) engines use these exact coils and plugs. Just visit a wreaker and get another plug, chances are it will be just fine. If that fails, start looking to other Toyota cars aged between 1990, and 2000.
There is no real reason why that coil plug could not be used for testing, but why would you. It could induce a fault, causing you to doubt your work (perhaps all of your work, if you’re new to wiring engines) and make you have the de-moralising task of going over all your work in detail, stuff that, fix the problem and move forward from there, not sideways.
9.6 Heat damageIf you find the engine your about to purchase has alot of broken plugs, reconsider the purchase or negotiate a lower price, if all the plugs are very brittle it does not bode well for the condition of the engine, it might be clean the exporter in Japan, or the importer in New Zealand washes them well, but if plugs are baked so was the engine (over and over), expect possibly of real mechanical problems if the plugs are falling apart in under a firm squeeze.
9.7 Heat damage reasons ?A another possible reason is Ultra Violet Light damage, or perhaps an engine that spent alot on time in traffic, so it's done 100k in distance and 250k in hours!, sometimes importers stack (already baked) engines up in a open yard, they sit in the sun for months and bake, causing the plugs to become brittle and weak, brittle plugs are not a good sign for the engine, means heat and sun will have effected other seals, cam cover seal to a certain point it’s ok to think the engine might be mechanically fine though.
9.8 Before removing the lower plastic housingI don’t normally feel the need to remove the entire loom. I tend to just free the loom up to the forward plug on the passenger’s side and the water temp sensors. I know above I talk about removing the entire loom. I also write about being very careful doing this because of the age of the plugs and there propensity to break apart. Really try to avoid going too far here.
Before you start removed the plastic mouldings/casings/housings and of course, the rest of the loom, consider the above comments on heat damage. Forward (of the engine) end of both plastic mouldings are plugs which may need to be unplugged. These will all be at risk of breaking easily, so will injector plugs passengers side set of plugs are particularly at risk. I'm very wearily of unplugging the four pin plug which carries the crank angle signal, passengers side camshaft sensor, they always seem to crack this plug no matter how hard I try not to. You do not 'have too' remove the entire loom like this, just .. look all I’m saying is be careful, really careful.
9.9 When you've got the loom offWhen you get the looms off it will probably dawn on you that it looks like a pretty substantial piece of kit it’s around 80 odd wires, each single wire breaks down to a simple connection like this, battery cable. Each wire is just a single connection it’s not that hard to work out where they need to go.
9.10 Wiring up the MAF / Air SensorThere are two types of 1uzfe mass air sensor, the older pre-95 cast alloy bodied type, and the later model plastic bodied type. The wiring for each it totally different.
Pay attention to the different configurations of the two Air sensing devices on the 1UZ-FE engine. It’s easy to look at the wrong diagram and be thinking you’ve made a mistake or feel confused.
9.10.1 Karmen Vortex Air Flow Meter
The Mass Air Flow Sensors converts the amount of air drawn into the engine into a voltage signal. The ECU needs to know intake air volume to calculate engine load. This is necessary to determine how much fuel to inject, when to ignite the cylinder, and when to shift the transmission (if there is an Automatic one present). The air flow sensor is located directly in the intake air stream, between the air cleaner and throttle body where it can measure incoming air. There are different types of Mass Air Flow sensors. The vane air flow meter and Karmen vortex are two older styles of air flow sensors and they can be identified by their shape. The newer, and more common is the Mass Air Flow (MAF) sensor.
This air flow meter consists of the following components:
- Vortex Generator.
- Mirror (metal foil).
- Photo Coupler (LED and photo transistor).
Which result in a measurement of 'air flow volume'
9.10.2 Karman Vortex Air Flow Meter OperationIntake air flow reacting against the vortex generator creates a swirling effect to the air downstream, very similar to the wake created in the water after a boat passes. This wake or flutter is referred to as a "Karman Vortex." The frequencies of the vortices vary in proportion to the intake air velocity (engine load).
note: do not remove the honey comb, it effects the operation of the device. You wont wreak it, but it wont measure as accurately so leave it alone.The vortices are metered into a pressure directing hole from which they act upon the metal foil mirror. The air flow against the mirror causes it to oscillate in proportion to the vortex frequency. This causes the illumination from the photo coupler's LED to be alternately applied to and diverted away from a photo transistor. As a result, the photo transistor alternately grounds or opens the 5-volt KS signal to the ECU.
This creates a 5 volt square wave signal that increases frequency in proportion to the increase in intake air flow. Because of the rapid, high frequency nature of this signal, accurate signal inspection at various engine operating ranges requires using a high quality digital multimeter (with frequency capabilities) or oscilloscope.
9.10.3 Later Model Plastic TypeThere Air flow meters work by a different principal and are a much cheaper device to make. The air flow cools a piece of metal which is suspended between two wires. There is one difference between them and earlier type is the plug has a different configuration, so pay attention to wiring, as the pins are different.
9.11 Wiring up the Camshaft sensors.The camshaft sensors are one of three speed positioning sensors. There is a little tag (protrusion) on the camshaft’s toothed cam belt wheel which the G and G1 sensors pick up on. So, what does the ecu do with this information? Well by knowing the position of number 1 cylinder and that’s in its compression stroke the ecu can use this information for fuel injection timing, direct ignition systems and variable valve timing.
The factory ecu will not run at all without both G sensors being connected correctly. There is a diagram below which shows the connection path to the ecu, I don’t normally need to interact with the wiring for them or the crank speed sensor.
9.12 Wiring up the Crankshaft sensor.In order to correctly time spark and injection events, the ECU monitors the relationship between the Ne and G signals. With most engines, the ECU determines the crankshaft has reached 10' BTDC of the compression stroke when it receives the first Ne signal following a G1 (or G2). Initial timing adjustment is critical as all ECU timing calculations assume this initial 10' BTDC as a reference point for the entire spark advance curve.
The Crankshaft sensor wiring travels down past passengers side plastic cover, stops at the coil and then continues onward down to the lower pulley. In there is the sensor it’s self and a small toothed wheel.
The engine speed sensor is the crank shaft sensor. It travels around in a shielded wire which is basically two wires in a flexible woven wire casing then covered in a plastic casing. The shielding is to protect the signals from interface and at the ECU end needs to be earthed, you can basically collect all the shielded wire up and earth the lot in one go.
Each tooth generates a pulse, in AC wave format. There is no external power source required. As the gear rotates faster there are more pulses produced. The ECU determines speed based on the number of pulses received and then applies the correct ignition and fuel maps in accordance with air volume (MAP/AFM) and air density measurements (air temp). The number of pulses in one second is the signal frequency.
This is how the NE sensor looks in the factory set up (above and below images). As above there is a toothed wheel, the sensor picks up on a cap and reports that to ecu. The toothed wheel is in fact only an 8 tooth. Which is stuff all definition. In performance engine setups there are 63:1 setups not 7:1. The increased definition allows for the removal of the ‘G’ or camshaft sensors and complete reliance on the NE sensor as a high definition source of crank positioning. Do not replace the factory toothed wheel unless you are replacing the ecu completely for an aftermarket one.
9.12.1 Ignition Timing StrategyThe ECU determines ignition timing by comparing engine operating parameters with spark advance values stored in its memory. The general formula for ignition timing follows:
Initial timing + Basic advance angle + Corrective advance angle = Total spark advance.Basic advance angle is computed using signals from crankshaft angle (G1), crankshaft speed (Ne), and engine load (Vs or PIM) sensors. Corrective timing factors include adjustments for coolant temperature (THW) and presence of detonation (KNK).
9.13 - Wiring up the O2 Sensors (four?)In so far as I know there are two kinds of 1uz-fe o2 sensors. The heated four wire kind, and the older two wire kind. Of course you find the older two wire kind on the older engines, pre 1991 (yes there are older 1uz's). The four wire kind have a powered heater in them to get them into a operational range and keep them there. The heating system has to be hooked up for the o2's to work. You do want the o2's working. The are not wide band sensors, just the on/off type. The wide band sensors tell you how much oxygen is left in the exhaust gases, factory sensors do not, they just say to the ecu something like ‘o2 found = add more gas next cycle’ and ‘no o2 = use less gas next time’.
9.13.1 ... four o2's / some engineIf your motor has two o2’s on it and they are heated four wire ones. It’s quite possible it might need two more. If it's a later model engine (1995 perhaps earlier; onwards) so that’s the OBDII engines (note can still pull OBDI codes from checklight). Look some 1uz’s have four, and as far as I know do need the other two to get the engine to run in open loop (ie normally). The only way to tell is to look at the loom and if you see two separate bundles of o2’s wires then you will need another two sensors to install OR use my work around which it detailed below.
The Ecu uses the difference between the two o2 sensors to determine if the catalyic converter is still working, on each bank of the v8. So, the ECU expects the cat to be there. There idea is for there to be a difference between the two o2 values, so you cannot put them in right next to each other. If your going to use all four put one on or near the header, and one well back after a muffler is ideal to clear the ecu of codes, per side. If you install the o2's near each other you will clear the sub o2 code, but a new code could show up about the condition of the CAT. If you going to do that you might as well just wire the primary o2's to the sub o2 pins and clear the code that way, leaving the non critical CAT code to come up and leave the engine like that. It's not like it's a big deal that way.
These extra o2's are not normally included in with the engine, they are actually bundled into the body/chassis harness because physically they are after the cat.
9.13.2 Two o2 sensors operating as fourYou can clear the sub o2 code by connecting OXR2 directly to OXR1 and OXL2 directly to OXL1. I do not connect the heating wires (e.g. (HTR2 to HTR1 and HTL2 to HTL1) there was/is not any point in doing that since it wont clear the code at all. This cleared may have cleared the primary o2 code for the left bank that I was getting in one install.
This gives the ecu two fake secondary o2 sensors (ghost ones), the problem is that there is no difference between them and the primaries, there should be a difference between the values that the primary and secondary o2's put out in a factory engine. However, it clears the code, removes closed loop mode (limp) and hey, thats the goal.
Note: this was tested by two other installers on the 6th and 7th (Dec 2011), both reported that it clears the code and closed loop (limp mode).
9.14 - Wiring up the InjectorsThe injectors are actually really simple, they get a constant feed of positive power from a switched power supply which I like to put on a relay which is switched by the ecu (MREL), but there is no good reason it cannot be off the key.
9.14.1 1uzfe injectors.The 1uzfe injectors are paired from 1989 to 1995, and sequential after that.
The paired injectors are set up like this,
Note the sharing of the cables for the ecu side. The splice is FAR up the loom, if you planning on running sequential injection later move the splice down to very near the ecu when your wiring the engine up.
At the Ecu end it looks like this: the pin has the usual plug location, and pin number, but the designation is the special #number, so #30 in this case is injectors 6 & 8.
I'm thinking this is so simple: I'm not doing to bother to do one for the sequential injection setups, on the post 95 or 97 engines, and the vvti engines, there is an image below which shows the set up, I'm sure you understand, dont assume #10 = injector one; it might well, but ya know = check it. It's just #10, #20, #30, #40, #50 etc. OR it's #1, #2, either way it's # something (hash) and a number.
A few more words, the older engines have mostly solid primary colours for the injectors (eg, red, blue, yellow, something else), but that doesn't mean some toyota worker hasn't just grabbed the nearest full spool and used that, so be wary, never assume.
9.14.2 Random fuel and Injector information.There are various ways to run injectors.
Group fire: where three or more injectors, say four, five, six, are fired at once.
Sequential: where each injector is fired separately.
9.14.3 Injector ConfigurationsPeople put alot of stock into whether or not an engines injectors are fired in a certain way. And there is some truth too it. The group firing is inefficient. Take the V6 in the Hilux surfs, it's a group fire engine, it uses what we call two 'injector drivers', one to fire one group, the other to fire the other group. This means to put fuel in 3# cylinder it has to put fuel into two others as well. However manufactures take this into account and reduce the amount of fuel being injected for what is pooling up in the air/fuel mix behind the valve waiting for the next 'open event'.
That said: the best foot I can put forward for grouped injection still translates to high fuel usage in the real world. The 3VZ-FE is still less efficient than the 1UZ-FE, I doubt it's just the injection.
Consider the early Holden 304 engine, it has two injector drivers, it group fires 4 injectors to put fuel into one cylinder, I've always mocked them for wasting 75% of the fuel they use by design, it's not a fair statement, but it is shockingly bad design. I mock the ms1 and ms2 ecu's for the same reason.
9.15 How to test the injectors1uzfe injectors are prone to seizing. This is caused by fuel deposits breaking down while the engine is idle and locking the 'gate' up. The method of dealing with this is to either leave the injector sitting in petrol for a few hours or then tap with a few times while running 12v across its two poles in an on/off manner. OR, leave them alone in place and tap the offending injector while the motor is running with a screw driver in a 'sharp' but NOT violent manner.
If you think the engine is not starting because of fuel spray aerostat or CRC cold crank while cranking the engine down throttle body into the intake. Beware this can cause burns to your arm hairs if you get a backfire. So take care now if the engine starts and half runs then the spark side of it is ok. Keep the basics in your mind. Motors need: air, fuel, spark and compression to run: bear that in mind and you'll be able to solve the simple problems which come up and have complex causes.
It's an injected engine, but that doesn't mean that it won’t suffer from a simple problem. It won’t run with no fuel, or spark, or a rag in the intake. Sure, it can suffer from very complex problems too, but it's VERY important to keep the simple stuff in mind too.
9.16 The Fuel Regulator & Pulsation DampenerIn the 1uzfe set up there is a pulsation dampener between the fuel pump, and the fuel rail. It looks like a regulator with no hose off it. If you put the fuel hoses on the wrong way around, it will not start.
Pulsation Dampener. (it evens out the fuel pulses from the pump, it does NOT impede fuel delivery, or power output (to a point), once your making 300kw's+ you might as well ditch this thing.
How you set your fuel system up is pretty much up to you. Bear in mind that two pumps get pretty noisy in a hatchback. Not to bad in a coupe with a back seat and some sort of barrier to the noise. Under the car is good place for them, but they are open to the elements there. Be realistic, if it's a stock engine, all you need is a decent EFI pump and you do not need a rising rate reg, and a surge tank, it all costs money, it's more things to fail and go wrong, keep it simple: the stock system works well, try it for a while then make changes.
Below we have an image from the megasquirt site which shows the basic fuel system. This image shows how the EFI fuel system is set up. It's simplistic, but it is very important to understand this.
This is the model for a surge tank set up, note the use of a low pressure fuel pump on the surge tank.
If you use a high pressure 'lift pump' then the fuel will hit the surge tank, find it to be full from the high volume lift pump, and back pressure will form behind the main pump, this pressure will then flow back into the fuel tank via the surge tank's relief line.
Pumps (high volume ones like Bosch 44's) move alot of fuel, so heat will start to soak into the fuel from the pressure and then into the tank. Once the tank starts heating up the heat just keeps getting higher and higher. Expanded fuel is less dense. Hot fuel is dangerous.
I made this mistake myself, the heat in the fuel lines and surge tank was clearly obvious; the hot fuel tank scared the shit out of me, I shut the system down immediately and disconnected the power. It was a big mistake to make, and it's not something a fuel cooler will solve either.
There is where the injector resistor goes, if your replacing the 1uz-fe injectors with bigger ones (assuming), that are low impedance; you have no need for resistors if you set up is stock factory.
If your injectors are playing up, or the engine doesn’t seem to firing on all cylinders there are solutions. It's very common for fuel deposits to cause the injector gate to lock up. Sometimes all it takes it to keep rev'ing the motor. Other times you have to tap the injectors while rev'ing the motor. If the injector(s) are really locked up you need to remove them, take the rubber seat off the bottom, and soak them in fuel for a day, then try tapping while switching them on/off (two person job).
If your really sure an injector is playing up, here's a tip from the Toyota manual for someone with some serious electrical gear floating around.
9.17 Wiring up the ECU to turn on.The Ecu turns on with very few wires. It’s all very well completing the wiring necessary to turn it on, but that it no help if you cannot confirm it’s on. It does not make an ‘I’m on noise’. The correct wires, and pins will vary ecu to ecu. Sorry, your back to the ‘get the right diagram issue’. But I work it out something like this: first I guess. I look at the plugs and try to figure it out and take a mental note of the wires I recognise. This is likely not help you much. I’m looking for
- +12V wired to pin (BATT)
- (+
and (+B1) both get 12volts when the Main EFI Relay is switched. - (E11) is grounded.
- (E2) is grounded.
- (E02) is grounded.
- (E01) is grounded.
- (IGSW) gets a switched power 12volts from the ignition switch.
From there I connect the W to a light, and the other ‘pin’ on the light as switched power. However you can also test if it’s on via the MREL output from the ecu (12+). To be honest there isn’t much I can do to help you here beyond saying find the wires and connect them. This is the final wiring set up on a 1992 ecu, note the fourth plug (far right) which has only five wires connected and the rest De-pinned.
9.18 Wiring up the Alternator.It might seem like a mystery but they are pretty simple devices. They get constant power, switched power, and have an earth connection for the charge light, which goes off when it’s charging, and is on just before you start the engine. They have no magnets in them so require an ‘exciter charge’ to enable charging. The Switched charge is the exciter it needs a 30amp fuse. Here is where the cables are located from factory.
- White (S) - Constant 12v feed (might be striped but it's always white as far as I know)
- Yellow Black (IG) - (this might be another colour, I've seen it red, solid black, yellow black, yellow (solid) blue (stripped) black, blue, use common sense) this is a switched wire that turns the alternator on so thats live when the key is at IGN (or stage two/ign on the key)
- Yellow (L) - (this one is always yellow as far as I know) when the alternator is on, it will earth out so run a ohms test against the shell to find it if you get confused) Dash Light, one side of the light goes to alt (earth side) and the other side should be live/switched when the key is at IGN (or stage two on the key)
This is another method of mounting the alternator if your not running other belts.
If you get stuck you can work out the wires using this method. Get to fuse holders, put 3 amp fuses in them. Work out the light wire if you can, by elimination applying work to the other two through the fuses expecting to blow a few. You'll figure it out pretty fast from there.
The Alternator has three wires. One has constant power. One as Switched power. One is a earth connection for the alternator charge light so you connect that wire to a 12v light (not an led unless you have a resistor on the power side otherwise it overloads it, and it starts smoking and then flames out, I know .. I did that yesterday with a 12v led) and to the other side of the light you put power.When the ignition is switched to IGN (stage two), you get a charge / battery light come on. When the alternator is working the charge light goes out, not if you screwed up wiring it though. If the alternator is running and working, you should see at least 13volts (13.25 – 13.8 perhaps) at the battery depending on the load from the stuff in the car that's running at the time. It's a 120amp alternator put a decent cable off it. Fuse that cable with a total of 120 - 140amp fuse(s) if you must/want/need too. off the alternator ? the fat wire is it's output wire, when working (when the constant power wire has constant power, the winder excitor wire has swtiched (stage two power), the charge light earth (which connects through the alternators housing) will come on, and the FAT wire will have 12v + @ 120amp.
I'd disconnect the battery to reset the ECU, and make sure that the acc belt is sufficiently tight. Measure the voltage on the battery with the engine off. Start the vehicle and let the 1UZ ecu set the ICV with the extra alternator load (learning ecu: needs to learn about the load of a alternator that's now offering resistance equal to 1-2hp or more). Check the battery voltage to make sure it is 'actually' charging. If this is a customers car repeat this check again before calling the job as 'done/finished/come get your car now'.
When you locate the wires, mark them properly aye. It's so easy to forget which one does what.
