No Running lights or interior lights

[DodgeH8TER]

So I was driving home today from work in my 1994 shortbus and all of a sudden my interior lights quit working. Gauge lights (not warning), heater light, Radio, power mirrors, shifter lights, etc. I still have my dome lights and headlights. Brakes and blinkers work as they should and I messed around with a bunch of interior fuses. So now I’m asking you guys for some guidance. I looked at some other threads but to come to no avail.

 

[DodgeH8TER]

Well I went through and found the blow fuse. #2. So I put in a new 15A fuse and it immediately blew. Put a 20A fuse and my radio crackled a little bit and I thought I smelt something burning. So I immediately pulled it back out just in case. So I have a short but not a massive one. I installed a new radio yesterday and in thinking either it’s the culprit or when I was pushing wires around and fitting it into place I bent one in the wrong way and it’s not grounding out. I’ll come back and let you guys know

 

[ajax1]

This is how you start fires. If the fuse blows immediately then running the non correct fuse for that circuit is not smart. If you smelt burning you probably got some new or future issues.
From the sounds of your hard to follow wire job you did on the stereo, why would you not just buy after market harness and use the Toyota wiring for the aftermarket radio. Use the two grey plugs, unplug the factory amp, follow the directions, plug in harness, done.

 

[jonheld]

Well I went through and found the blow fuse. #2. So I put in a new 15A fuse and it immediately blew. Put a 20A fuse and my radio crackled a little bit and I thought I smelt something burning.

Wow. So let's use this as an example of the absolute wrong thing to do folks.
I mean, really?

 

[Kernal]

FWIW about 10 years ago someone had their cowl harness (main harness bundle behind the dash) burn up when a cheapo Chynesium replacement fuse didn't pop when it should have. Not the same cause but (almost) similar result.

Smoked Harness: Lessons Learned

I noticed my taillights were out last week. Found the 15 amp fuse blown. Replaced it. I knew I had to have a short someplace, but it wasn't showing up… No problems until Sunday when I was making a four hour trip home from Island Park. Getting dark. Turn on the lights and no taillights. I had...

forum.ih8mud.com

 

[mudgudgeon]

Trouble shooting 101.

#1. Fuses are there to save you from an even bigger problem

Also #1. If you did work on a vehicle, and then you have related problems come up, you probably fooked something up.

Check all your work, and anything adjacent that you may have disturbed accidentally. Like pinched or damaged wires

 

[truthdetector]

Installing an aftermarket radio *without* unplugging the factory amp will cause the fuse to blow.

 

[NeverFinis]

Installing an aftermarket radio *without* unplugging the factory amp will cause the fuse to blow.

Doesn't this depend on which conversion harness you use?

The Metra 70-8112 Wiring Harness, which I used, keeps the factory amp.

I am not blowing fuses.

 

[truthdetector]

Yes, it does depend. OP's description suggested that maybe a recently installed radio using the harness that bypasses the factory amp without unplugging it could lead to blowing fuses. I realize I'm making some assumptions, but wanted to put it out there as a possibility for OP before they start a fire by installing larger fuses.

 

[BILT4ME]

Wow. So let's use this as an example of the absolute wrong thing to do folks.
I mean, really?

Good thing the truck doesn't use the old barrel glass fuses or he would have installed a 22LR.......

 

[Kernal]

It's a rough crowd tonight but I had to look that up:

 

[DodgeH8TER]

This is how you start fires. If the fuse blows immediately then running the non correct fuse for that circuit is not smart. If you smelt burning you probably got some new or future issues.
From the sounds of your hard to follow wire job you did on the stereo, why would you not just buy after market harness and use the Toyota wiring for the aftermarket radio. Use the two grey plugs, unplug the factory amp, follow the directions, plug in harness, done.

Yes you can jump sizes. All circuits in a car are rated about 10 amps for than their fuse is. I put it in for about 2 seconds, so not enough time for wires to get hot, especially on a 12v system. I’ve seen some alternator wires have close to 60V going through them and even then it doesn’t fry the system in a couple seconds.
And for the reason is it had an older radio with the factory connectors so I didn’t have to. I just had to cut and re solder the wires on the old adapter connectors. That and I wasn’t about to drop 500$ plus on a radio for it

 

[DodgeH8TER]

Wow. So let's use this as an example of the absolute wrong thing to do folks.
I mean, really?

A 5amp jump isn’t insane. Now if it’s 10 or more yeah we’d have issues. I was purely checking the amperage drawn to see if it’s a major short. When you check it with a Multimeter you are doing the same thing and just completing the circuit since in order to test amperage on a circuit you have to run it in series

 

[DodgeH8TER]

Trouble shooting 101.

#1. Fuses are there to save you from an even bigger problem

Also #1. If you did work on a vehicle, and then you have related problems come up, you probably fooked something up.

Check all your work, and anything adjacent that you may have disturbed accidentally. Like pinched or damaged wires

Oh I know exactly what it could be. I’m gonna pull and unplug my radio next and try the fuse again. If it doesn’t blow and I plug in the radio and it pops, it’s the radio. If it doesn’t pop with the radio plugged in I got a loose wire somewhere that has a 12v supply that’s grounded out. Luckily inside the dash there’s more plastic than metal so it will be easy to find

 

[DodgeH8TER]

Yes, it does depend. OP's description suggested that maybe a recently installed radio using the harness that bypasses the factory amp without unplugging it could lead to blowing fuses. I realize I'm making some assumptions, but wanted to put it out there as a possibility for OP before they start a fire by installing larger fuses.

So I’m wondering in which wire the factory amp runs through.

 

[LongDuck]

I got a loose wire somewhere

I agree on this is likely the cause.

 

[BILT4ME]

It's not the voltage......

It's the Amps.......

 

[jonheld]

A 5amp jump isn’t insane. Now if it’s 10 or more yeah we’d have issues. I was purely checking the amperage drawn to see if it’s a major short. When you check it with a Multimeter you are doing the same thing and just completing the circuit since in order to test amperage on a circuit you have to run it in series

And right there is why I never let anyone touch any electrical on my truck. Lotsa luck.

 

[NeverFinis]

I am someone who has gone over Toyota's wiring very closely while doing my LS Swap.

I am always very surprised how light the wiring is for a given load and length of the circuit.

GM wiring is the same way for their engines. 0.5mm² (20 AWG) is fairly common for both makes.

They are very well engineered to carry a given load for a given distance. Fuses are their to protect the wiring from a larger load.

You know what I wouldn't do? Increase the load and expect good things to happen.

In all my years, I have never installed a larger fuse to test a circuit.

You know what you do? You test the resistance on a circuit with the Ohm function of your multimeter. Test for continuity end to end. If it is a short, test against GND. No power? Test against PWR.

This will tell you everything you need to know without potentially causing damage to the harness.

 

[mudgudgeon]

I guess your shop teacher taught you about wiring too

i know this ain't a Toyota part, but I think you might have a use for it . . .