1989 4 Runner lost Head lights & full beam

I have been looking at a wiring diagram and it looks like the headlamp relay may be the cause of the problem, but I cannot find it.

Can anyone tell me where it is and how to identify it?

"Hi,

Merlin,

I'm not sure if the '89 4Runner is the same, but my '90 has a headlight relay in the same box where the fuses are located inside the engine compartment. Make sure that the relay is working. You may need someone to turn the lights on and off while you touch the relay to feel if the coil is at least operating. Even if it does "feel" like it is working, that doesn't mean that the circuit is completing. Bad contacts might be causing the intermittent operation. You should be able to momentarily bypass the relay to light the lights. On mine the small connectors are for the coil and the larger ones are for the lights. That still doesn't necessarily mean that the relay is bad. You can get a cheap one from Radio Shack to use for testing as I learned from another poster here. It won't be a direct plug-in type but you can make the necessary coil and load connections to see if it makes a difference. Just be sure that nothing touches bare metal and shorts out.

You didn't mention if the vehicle has had any modifications done to it such as the addition of plow lights. That's where my problem was. Whoever installed the plow lights used Scotchlocks, which aren't recommended. Use insulated crimp type butt connectors or solder with shrink tubing for best results. I've seen some new posilock connectors on the market, but haven't had a chance to try them out yet.

If you do a Google search, you should find some of my past posts where this was discussed with another fellow who was having a similar problem. Hope this helps. Post back your results here.

Peter.

I found the relay which was under the bonnet. I tested it across the battery and it works ok. But will not click with the stalk switch. Looks like I am looking for a bad connection somewhere. it's a bit cold though for this week. Might have a look next week.

OR, you have a bad stalk switch. (It's actually called a Combo Switch.)

Since the relay itself seems to be good, I'd be chasing down the combo switch before looking for a bad connector. My logic is that the combo switch is a dynamic device -- it changes its condition on a pretty regular basis as you make your various demands -- but the connectors are static devices that never change state. My guess is that the dynamic device has failed, not the static one.

Merlin,

In my effort to repair my headlight problem, I found the following link. I had forgotten to mention it in my previous post.

Lots of information and task specific details there. Be sure to look around the whole site.

Hope this helps.

Peter.

Thanks very much for the info, I was actually talking to a firebrigade mechanic today who told me to look in the column to see if the switch was worn or dirty. A job for the weekend I think. Thanks for the link, it looks good so at least I seem to be on the right track now.

I will update on the weekend. Thanks to you both for helping me out.

Today I have checked the relay (it clicks and makes contact) took steering wheel off and metered the switches and all seems ok, Looked for any bad connectors and thought about taking the headlamps off and follow the wiring back, time started to run out. Got fed up and put it all back together for now, try again tomorrow, but if any thoughts I would be grateful.

Have you actually got both an earth and 12v at the light connections on the back of the lights? I know its the most simple answer but are the lamps blown?

If you don't find anything else, clean all the contacts dealing with the lights in the combination switch with fine sandpaper. You can disassemble the light part from the rest.

Another frustrating day!

Went out again but it sure was cold, moral was a little low, started checking voltage and for some reason I cannot get voltage across the 2 10amp fuses, (1 for left other for right) but I found that if I short across the 2 large terminals on the relay the head lights come on. So I thought it may be the relay. I took my relay to a friend who has a Hilux and luckily the same relay, swapped them around and my relay works on his. So it is not the relay. Got fed up at this stage and come back home.

I got a day off Tuesday, I will keep you updated. Thanks for all the comments, I will be trying the contacts again.

Finally sorted (kind of)

Spent all day out with it today and found that the white/red from the relay which I presume went back to the switch connector had a break in it somewhere. From the relay I followed it in the loom along the front of the truck by the grill and it metered ok to the relay (used a pin to insert into cable) when it got to the front nearside light the loom disappeared behind the air con unit and I could not find where it went. From the stalk switch connector the red/white went up behind the dash and I lost it although I took the glove compartment out and part of the dash. So I ran a short cable from the relay connector box to the stalk switch connector, soldered it and all seems to work ok now. I have also ordered a Haynes manual as I have not got a wiring diagram as it is a 1989 Australian 2.8 non turbo import. I may look at it again one day.

Thanks to you all again for all the help.

Mike

Merlin,

You might want to take a look at the following link:

From what I've learned here, you can get access to the manual downloads for something along the order of $10 a day.

Unfortunately, I bought a manual (either Haynes or Chilton - not sure which one) at a local auto parts store for $20 and it leaves a lot to be desired. Not like the manuals that I was used to using in the past.

One note though, I have not downloaded the manuals from the above link. I keep telling myself that I should do so, but just haven't gotten around to it. You may want to search some of the Toyota groups for more feedback before you decide to do so.

Glad that you were able to resolve your problem.

Peter.