02 tacoma locks, dome, radio issues

Friend of mine has a 02 Taco that the power locks would randomly quit working. Along with the locks, the dome light would stop working, and the radio would also quit working.

I pulled an old POS keyless entry system out & installed a new 5901. The entire day I had the truck everything was working fine. All fuses had been checked & there were no blown ones, under dash or under hood.
That night everything quit working again out of the blue, so it must not have been the old keyless system, although it had been tied into a few wrong wires in the dr kick panel. (it was an ugly mess)

I had checked over everything & all the OEM wiring was fine, and I only had to repair a couple wires.

Does anyone have any ideas? I noticed a control module in the kickpanel, but have yet to determine what its for.
Ive also read the dome light circuit is tied into the locks (& possibly radio?). Fuse is good, but there is a dome light relay I plan to check into too.

Any ideas would be greatly helpful.

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Unless it raises the hair on the back of your neck, its only noise!

You DON'T need dome light control on post 2000 Toyotas, it's built into the factory locking system.
Look at the internal fuse box, open it up and that's where the problem lies.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

You seem fairly confident the issue is in the fuse box, any reasoning behind that? (to understand for myself, not being an ass)

I could care less about the dome light, but from what I have found thus far it seems the dome power circuit is shared by the ECU backup, radio backup, & possibly the locking system.

I believe the flaw is in the locking system due to the bad previous keyless entry install, and its damage done is effecting the other stuff down the line.

Cracking into the fuse box will be at the top of the list when I get to rip the truck apart again.

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Unless it raises the hair on the back of your neck, its only noise!

My background is auto electric diagnostics, I've seen this problem on a Yaris here in the UK, the stealership blamed the alarm installers, I was called in as a neutral, yes it was the in dash fusebox, also happened recently on this site, a Camry, hence my post so look at the obvious before changing expensive components, check and test.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

You checked the fuses.

Did you swap them or rotate them?

If not, rotate all same sized fuses. See if the problem moves to another circuit.


Otherwise, whatever Howard says....

Howie:

Any mechanic will be quick to point the fingers at alarms & stereo systems when they cannot figure out an issue. My experiences have taught me early on that the majority of mechanics have no real idea about electronic equipment or even 12vdc.

Ive never run into a problem where the fuse box was the issue, and it does make sense. What should I be looking for inside? Or will it be pretty evident once its open? I just dont want to say "yeah, we'll rip open the fuse box & fix it right up" and then look like an idiot when that was not the problem, ya know? Can you explain specifically what is going on inside the fuse panel? Loose connection, corrosion? crappy to begin with?

I searched on here, google, yahoo, even toyota forums trying to find similar issues. I found nada. I will search for the camry on here, thanks for the heads up.


Oldspark:
I always test fuses with a DMM, just a habit of mine & takes out the guesswork.

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Unless it raises the hair on the back of your neck, its only noise!

Electrical info overload, which fuse box, which processor etc.
In both cases an in or underdash fuse box linked to the ignition switch, internal circuitry failed. Find something in common, the dome light is fed off that fusebox, although dome light power on Toyotas used to come from the underhood unit, its a real hunt now. Also all the fusebox plugs, did you jerk on one whilst installing the 5901? Did they all work before?

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

They had problems before the 5901 install, and from the time I removed the old system & installed the 5901 everything was working fine.
That night after driving the truck around everything quit on him again.

I did not pull on any of the wiring, didnt even need to the install was a breeze on this truck with everything easily accessible. lol

Are you talking circuit board type failures/faults? Had the truck been acting up while it was in my hands Im sure I could have better diagnosed it, but as it is now all I can go off of is what the owner tells me.

Also couldnt find the thread about the Camry on here, but still looking.

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Unless it raises the hair on the back of your neck, its only noise!

The post was called "fuse panel" the vehicle was a Lexus but that's the same any way.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

audiophyle_247 wrote:

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I always test fuses with a DMM, just a habit of mine & takes out the guesswork.

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Yes - but that is not a full test - it does not pick up thermal fractures. (Fractured but not a problem until heated. It cools down and is ok again. A mate disposed of his beloved new $28,000 super-whatever-car after 2 years of intermittent EFI dying and intense troubleshooting. He found it a few days before disposal.)

Hence ROTATE the fuses.

Trust me - do it. It is the only way to eliminate intermittent fuses.


DMMs similarly miss glass fuse breaks which are far more common through poor fuse to end-cap bonding (fatigue, CHeap, etc).