headlight problem

[Mitch.W]

toyota mark 2 lx70 1986. so yeah had this problem since ive owned the car and now im sick of it. when the cars turned off with the headlights on they are sweet. but as soon as i turn the car on they start pulsing (party spec) if i rev it gets worse as you can see in the video it. also its every light in the car that does it e.g. dash, clock, heater controls etc. could this mean the alternator is fucked? 

 

its kind of hard to see in this video but the best i could get on a iphone while on my way home. 

 

[kyteler]

Possibly the VR, if it's external, replace it, if it's internal, get another alternator.

[anglia4]

What kind of car?

 

Would it have a bi-metallic circuit breaker somewhere?

 

I know on my old mustang, it has a bi-metallic circuit breaker in the headlight switch, so when it draws to much current, the bi-metallic gets hot and bends and breaks contact, then cools down and contacts again. Making the lights flash. They do this all the time when they get a bit old and fucked.

Easy fix, run the headlights on a relay so the current draw on the switch is tiny and doesn't overheat the bimetallic.

 

 

May not be your problem but something you could look into.

[Mitch.W]

ahh its a toyota mark2 1986 (turbo diesel)

[Frosty]

From your description the regulator in the alt is about to fail but read the rest and have a fiddle, I could be wrong. The older I get the more that seems to happen.

As far as I know the fuse/breaker for the Mark 2 is load sensitive to make it blow not a bi metal one which means they don't go on & of but just stop going all together on one side, they run a left and right circuit with both a relay and a fuse for each side.

Because it is affecting the whole system (indicated buy the dash lights also dimming, that circuit is independent from the main lights) would send me looking at things that can affect the whole system.

Try a volt meter across the battery with the lights on and of checking how much it changes and fluctuates under load.

Then do the same thing at the alt. (one probe on the main wire out and the other on the body of the alt).

A small difference in the readings (less than 1 volt) between the battery and the ones from alt would mean the alt is the problem.

A larger difference would mean the wiring is at fault, if this is the case check the earths for the headlights and the engine to body one also.

 

Couple of other things to check is the relays and the fuses for the headlights (corrosion builds up over time causing problems) give the connections a clean up with some sand paper.

From memory the LX-70 series run a vacuum pump on the back of the alt which has oil running through it and I have seen these leak forcing oil into the alt with some very strange effects.

 

A load test of the alt could prove helpful as well. Start the car and turn the lights on full, then disconnect the earth side of the battery. The lights will dim a little and you will see a drop on the volt meter , 14volts is a normal reading within a volt or so and it should stay close to that with the battery disconnected, a big drop/dimming means the alt is getting worn out.

Another easy check is to turn on the lights with the engine of, if it still does the dimming thing even when the engine is of its the wiring.

[Unclejake]

 

when the cars turned off with the headlights on they are sweet. but as soon as i turn the car on they start pulsing (party spec) if i rev it gets worse

That's normally an alternator problem mate (rectifier/regulator thingy). Cheap and easy to sort.

I haven't looked at the video, but alternator would be the first thing I'd check/change. It won't be doing your stereo etc. any good either

[ta63-1uzze]

the first thing you should check is the earths , and by check I mean  remove and sand and clean your earth straps, this could be as simple as not having a good earth on the engine. you should have a couple earths at least. normally one big around the starter and maybe one or two smaller ones , so clean them and see if it helps .

 

if that doesn't help at all I would be looking at getting your alt bench tested at an auto electrical shop. they spin them up and load them up . best way to check it to be honest : )

[Mitch.W]

sweet! thanks everyone for the help! i will have a play around when i have some spare time off work. ill just do all of the above and if all fails ill take the dive and buy a brand new alt. 

[FuzzayD]

if the pulsing doesnt get faster with rpm i would say you have an earth fault most likely some sort of interference causing the pulsing like a stereo or if its more frequent when on a bumpy road you could have loose connectors or bulbs.

[Mitch.W]

checked all my connections and earths. pretty sure i need a new alt. i