Headlights shut off every 30 minutes and switch has to be reset

Hey folks,

I have an issue with my headlights that I can't figure out.

Truck is a 2002 Regular Cab 4x4 5-speed with the 2.7. Base model with A/C.

Aftermarket stereo, amp, and speakers installed after the issue popped up, so I doubt they're affecting it.

About every 30 minutes, the headlights shut off while driving or while parked. I can turn them back on, but it requires turning the multifunction switch to "off" and then back to "on." They will stay on for another 30 minutes or so and do the same thing.

I tried a new multifunction switch, but it didn't work, doing the same thing. The factory switch seemed to get slightly warmer while the headlights were on, but it's difficult to tell.

Tomorrow, I will try replacing the relay, but it seems unlikely to me that a bad relay would be this consistent. It also seems unlikely that a wire grounding out and causing a short would be this inconsistent.

I have heard that these trucks have an auto-shut off feature after the headlights have been on for 30 minutes and the key is in the "off" position. Is that correct?

Has anyone experienced this type of issue before? The last thing on my mind is that there is an issue with sensing that the key is in the "on" position.

Any advice? If I can't get a fix here I'll have to take it somewhere for an electrical diagnostic, which I would prefer not to do.

Thanks in advance.

 

I know I've dug this thread from the grave but wondering if anyone else has had this issue and if so any idea what the issue is. I have an 01 Tacoma doing the exact same thing and don't have a clue what it could be??

 

A guick google search turned up this hit:
http://www.tcamanual.com/automatic_light_off_system_if_equipped_-166.html

Its about a Camry, but I'm sure that all Toyota 'auto off' systems work the same.
From I read there, I would first suspect a 'hood open' sensor failure.

 

Ok thanks for the link. When o bought the truck I know that the door chime has never worked since I've had it. I wonder if that could have anything to do with it thinking a door is open or something?

 

Hi all,
sorry for the graveyard dig for a second time, But did either of you ever figure out this problem. I have the same thing happening with my 03 Tacoma.
Thanks

 

I doubt the above link is the issue.

There's no "hood open" censor on a 1st gen Tacoma. Not sure there's even one on 3rd gens. The link is talking about doors and trunk, anyway.

The lights turn off immediately when you open the doors, at least the ones on my 2004 do.

Have you timed how long it takes the lights to shut off?

My thought is it might be the relay or something.

 

Hi jbrandt,
I agree with you the the above link is not the answer. The head and dash lights turn off after about 30 minutes of driving. I can bang on the relay and it the lights don't go back on so I don't believe that it is any sort of arcing / "carbonization" on the High amperage side of the relay. The fix so far is to turn the headlight rotary off and then back on again. I have not driven at night long enough to see if it happens more than once, and so far the old off/on trick has worked. I currently am thinking that it is a ECM timer issue but wanted to see if any one else has had the problem and found a fix for it without taking it to toyota. I have got the electrical manual so I will trouble shoot further. Thanks
Aaron

 

You know you can drive during the day with your lights on, right?

What about your high beams? Do those work, or do they not come on either?

Headlight relays are like $15, OEM ones are redonk expensive, like $80.

Also, put the "@" symbol in front of my (or other people's) name so we get a notification that you replying to us.

@alsprost

 

@jbrandt Thanks for the tip. When the lights shut off the high's don't work either. I am going to replace the relay, but I don't think that is the problem. The issue to too repeatable and time able, which on one hand is great, but on the other hand it only happens every 30 minutes. Probably gonna go through a tank of gas this weekend, if I can't make the same thing happen without the truck running and a battery charger going. Thanks for you thoughts on this matter.

 

I wonder if maybe heat related? Like it takes that amount of time to heat up the engine compartment, and thus affect the relay (or whatever is causing it)?

Another possibility is your steering column switch. Bad switches do some weird things. Or maybe a bad ground...

But for $15 I'd at least try the replay, and if it still does it, even if it's a cheap auto part store brand one, it's not likely to be faulty right off the bat. If the problem persists, you can always return it (hopefully).

 

My guess (just a guess at this point) would be relay as well, and the timing due to a rate-of-heating effect somehow.

What voltage do you have at the headlight connector? Check each one. Grounds can get tricky sometimes.

 

Quoted from the 2003 Wiring diagram of the auto off headlights:

"The light auto turn off system automatically turns the taillight or headlight off according to the door open or close on the driver’s side, and prevent failing to turn off the lights. If the ignition switch is turned to OFF from ON with the headlight or taillight is on, the signal is input in the body ECU. If the driver’s seat door is opened at that time, the signal from the door courtesy SW front LH is sent to the body ECU. The signal turns the headlight or taillight off by the body ECU."

If it's not the relay, it could be either the ignition switch or the door courtesy switch sending a signal to the body ECU to turn the lights off.
One way to check this is to see if your taillights/running lights also turn off when the headlights turn off. You will need to exit the vehicle through the passenger door to check this, otherwise you could get false results from the driver door courtesy switch.

 

I had a car back in the day with some kind of circuit breaker on the headlights. Overheat and they turn off, cool and back on. I don't know if they do anything similar in tacos.

A little troubleshooting like driving with just dash/parking lights on might give some clues.

 

@jbrandt It being heat related is a really interesting idea. I can easily check that out. After changing the relay of course. I can certainly take apart the steering column switch and see if it has any obvious reasons for the issue as well. I hadn't really considered that yet. @Indy

@4xdog I think I can keep one headlight out with the truck running and see if I notice a voltage change when the lights turn off. I can also pull some jumpers on the input coil side of the relay and see if it is something supplying the relay that has caused the headlights to go out as well. Thanks

@nzbrock Thanks for looking this up in the electrical manual, the timing is off for it to be that many orders of magnitude longer from the ECM auto shut off, It just seems to be incredibly regular, and that seems to me to be pointed at something possibly logic based. I will for sure need to check this without the engine running exiting driver side, and also passenger side ignition off and on to see if i notice any pattern there.

Thanks all, for all of your thoughts on the matter. I will let you know what I find out, hopefully this weekend, but possibly simply sometime in Februrary. It's always fun working on these things in the dead of winter. But at least I haven't had to drop a transmission in the snow yet this year.

 

next time they shut off touch the headlight 3 prong plug and see how hot it is. I am thinking there is a corrosion/bad ground and the load is overheating the relay.

 

Hey sorry to revive this but I'm having the same exact issue on my 2002. I've replaced the headlight relay but still having the same issue. Has anything else worked for anyone?