Brake switch wiring

Well here's the diagram from your manual. If you download the PDf all you have to do is search "brake lamp switch" and it'll show you all the pinouts and diagrams.

Looks like the 3rd brake light doesn't have it's own circuit. Power goes from the fuse block to pin 5 of the switch, then from pin 6 through several connectors until it splits off to the left/right/3rd brake light.

Bare metal is definitely a condition for a short to ground though so it's a good find!

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So...I got a new used wiring harness and re-spliced the melted connector. I'm pretty sure I got each wire where it's supposed to go since I cut and spliced old wire to new connector one by one. Changed the brake switch and still blowing the brake fuse immediately when I put a new one in the fuse box.

I cleaned up my wire exposure situation from the rear center 3rd brake light and those ends are covered now.

I'm at a loss...I thought for sure this new connector would be the answer but it's not.

I need suggestions. Where do I start now?
 
At this point what I would do is put a multi-meter across the pins in the fuse block to measure the amperage draw and start unplugging stuff until the reading drops to zero in order to narrow down the part of the circuit that has the short. Do you have a meter?

Edit: Check that, measure voltage rather than amperage... The short to ground may very well blow the fuse inside the meter
 
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qslim said:
At this point what I would do is put a multi-meter across the pins in the fuse block to measure the amperage draw and start unplugging stuff until the reading drops to zero in order to narrow down the part of the circuit that has the short. Do you have a meter?
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I do, I have a harbor freight freebie one, and if Im being completely honest, I don't know how to use it well. In the fuse block, Im loosing #2 immediately upon placing a new fuse--the key is off and it pops immediately.

Im also losing #13 (turn signals) when I place a new fuse, first time I flick a signal it pops---unrelated? maybe...I don't know.

But back to the meter. I can turn it on and stick in in each of the fuse ports...but I alredy know that #2 has power...unless im not understanding.

As you said last week...fuse 2 runs to pin 5 on the switch which is in the area of the melt, but what does pin 5 service? pin 6 is also melted, and it goes to the center mount stop lamp.

-multi-fuction switch?

If the meter is what I should do, then I'll figure it out with google or the users manual.
 
Ok, a HB freebie should work just fine. What you're going to do is set it to measure DC voltage and put the red and black leads on the fuse block terminals for the fuse that keeps popping. You're going to measure battery voltage across the fuse block terminals, and thats the problem; it should be zero unless you're stepping on the brake pedal. Look at your wiring diagram and find the connectors going down the circuit. Unplug them one by one and then check your meter - if you unplug a connector and the voltage reading drops to zero, you know that the problem is downstream of the connector you've just unplugged. If you unplug a connector and the voltage reading doesn't change then you know the problem is upstream toward the fuse block. This'll help you narrow down the branch of wiring that has your short.
 
qslim said:
Ok, a HB freebie should work just fine. What you're going to do is set it to measure DC voltage and put the red and black leads on the fuse block terminals for the fuse that keeps popping. You're going to measure battery voltage across the fuse block terminals, and thats the problem; it should be zero unless you're stepping on the brake pedal. Look at your wiring diagram and find the connectors going down the circuit. Unplug them one by one and then check your meter - if you unplug a connector and the voltage reading drops to zero, you know that the problem is downstream of the connector you've just unplugged. If you unplug a connector and the voltage reading doesn't change then you know the problem is upstream toward the fuse block. This'll help you narrow down the branch of wiring that has your short.
Click to expand...

Well, I kinda did something like this. I wired up a light powered by the fuse that keep popping. If the light goes off then I find the problem. I went around and unplugged everything I could find and get to reasonably. I also got a cable tracker and used the tone generator to try to find the problem. I got good tone over all 6 wires except the ground. It went out around the relay that sits next to the brake switch. So I fillet'd the loom to see if the ground wire was broken and it looked good. Rewired the connections to the relay, which I know was hot becuase I about got electrocuted because I was sweating so much, my hands were wet and that connector let me know it was hot when it got wet.

Anyhow, found that the gas tank ground wasn't grounded to the chassis....did that.

.......most importantly, there was one change that happened.
Now when I replace the blown fuse, it doesn't pop right away....only when I hit the brakes. So where does that leave me? Is it possible that the brake switch was blown through all the troubleshooting? I replaced it when all this started....what do you think?
 
Michelle Sweeney said:
Well, I kinda did something like this. I wired up a light powered by the fuse that keep popping. If the light goes off then I find the problem. I went around and unplugged everything I could find and get to reasonably. I also got a cable tracker and used the tone generator to try to find the problem. I got good tone over all 6 wires except the ground. It went out around the relay that sits next to the brake switch. So I fillet'd the loom to see if the ground wire was broken and it looked good. Rewired the connections to the relay, which I know was hot becuase I about got electrocuted because I was sweating so much, my hands were wet and that connector let me know it was hot when it got wet.

Anyhow, found that the gas tank ground wasn't grounded to the chassis....did that.

.......most importantly, there was one change that happened.
Now when I replace the blown fuse, it doesn't pop right away....only when I hit the brakes. So where does that leave me? Is it possible that the brake switch was blown through all the troubleshooting? I replaced it when all this started....what do you think?
Click to expand...

If the fuse is popping only when you hit the brakes it means that there is a short after the brake switch (between the brake switch and the lights). Also not sure what you mean about using a wire tracker and tone generator, are you talking about a multimeter with the audible alert for measuring continuity?
 
Michelle Sweeney said:
Ahh the saga continues. I started to fillet these wires apart when I noticed the connector for the brake switch is melted. It still fits into the switch....what do you guys think?

View attachment 103390
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Michelle, were you able to find that gray switch shown in the picture? I need to get one but every replacement plug I seer does not show the same. Thanks Craig
 
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