Truck brake lights don't work...can't find the cause.

[Zero Knievel]

Checking lights before inspection.  Brake lights aren't working.  Intermittent...now not at all.

 

Steps taken so far....

 

Removed switch and cleaned it.  Tested with multimeter...works fine according to the multimeter.

Checked every fuse having anything to do with brakes...all are intact.

Checked harness part that connects to switch.  I can detect current.

Tried checking with a test light...light will not come on.

 

I'm putting on the battery tender because it's under 12v (dome lamp on while I'm trying to work on the switch)...just in case.

 

I don't see how I can have voltage (11+) at the terminals but a test light won't even glow.

[Zero Knievel]

FWIW, the switch closes the circuit...in case someone thought it opened the circuit...telling something else to send power to the lamps.

[Zero Knievel]

Okay...I can detect voltage but no amperage...makes no sense.  Even with engine running (not that it's necessary to work the brake lights).

[Zero Knievel]

Okay, I am a retard.

 

I was checking the switch that disengages the cruise control.  I fixed it the same way I did last time...unplugged the harness from the brake sensor and plugged it back in.  Don't know why, but this always fixes the problem.

[XXitanium]

Make, model, year and color?

[Zero Knievel]

Mazda B3000 1998 Tan

[XXitanium]

General Electrical Module?

 

https://www.ranger-forums.com/general-technical-electrical-18/electrical-problem-1998-ranger-3-0-a-167462/

 

My wife and I replaced ours a few years ago. We saved hundreds of dollars, but it took a good deal of time.

 

 

[XXitanium]

....or....

 

.

.

.

https://www.ranger-forums.com/general-technical-electrical-18/riddle-me-major-electrical-problem-98-its-oddball-need-help-136394/

 

[blackhawkxx]

10 hours ago, XXitanium said:

color

So this is a race thing?  

[XXitanium]

No, O'Reily's joke I borrowed...

[Furbird]

So...um...no offense...but you started at the HARDEST POSSIBLE AREA.  I would have started at the bulbs and worked my way forward.  Then again I own GM's and it's always a bulb problem so there's that... (unless it's an Express van then it is, in fact the switch)

[SwampNut]

1 hour ago, Furbird said:

So...um...no offense...but you started at the HARDEST POSSIBLE AREA.  I would have started at the bulbs and worked my way forward.  Then again I own GM's and it's always a bulb problem so there's that... (unless it's an Express van then it is, in fact the switch)

 

He probably also did it all through the tailpipe.

 

[Zero Knievel]

12 hours ago, Furbird said:

So...um...no offense...but you started at the HARDEST POSSIBLE AREA.  I would have started at the bulbs and worked my way forward.  Then again I own GM's and it's always a bulb problem so there's that... (unless it's an Express van then it is, in fact the switch)

The lights worked intermittently.  This meant it wasn’t the bulbs.  The lights either came on or they didn’t.  They didn’t flicker once on.  That told me the odds were it was a bad switch or lose wire near the front of the harness and not the rear.  It also wasn’t the first time this happened and I fixed it…so I remember it being about the brake switch.

 

 

[Zero Knievel]

11 hours ago, SwampNut said:

He probably also did it all through the tailpipe.

What’s your fetish with anal?

[Furbird]

5 hours ago, Zero Knievel said:

The lights worked intermittently.  This meant it wasn’t the bulbs.  The lights either came on or they didn’t.  They didn’t flicker once on.  That told me the odds were it was a bad switch or lose wire near the front of the harness and not the rear.  It also wasn’t the first time this happened and I fixed it…so I remember it being about the brake switch.

 

 

Mine did the exact same thing.  It was a broken filament in the bulb on one side and a bad connection on the other (corrosion in the socket).  You could literally slap the taillight and the bulb would start working again.  So, again, no offense but you're starting at the hardest part of the vehicle to work on, under the dash, where I did 12v electronics for almost a decade.

[SwampNut]

8 hours ago, Zero Knievel said:

What’s your fetish with anal?

 

Most every guy here was thinking of the gynecologist mechanic joke, and a vagina, but....you do you, LOL.

 

[Zero Knievel]

3 hours ago, SwampNut said:

 

Most every guy here was thinking of the gynecologist mechanic joke, and a vagina, but....you do you, LOL.

 

The only version I’ve heard said the doctor was a proctologist…tailpipe…get it?

[XXitanium]

http://blonderunner.com/2011/02/the-gynecologist-who-became-a-mechanic-joke/

 

 

[SwampNut]

Gynecologist becomes a boat mechanic.  Did it all through the outdrive.

 

[superhawk996]

I just saw this and right away I knew (99%) that it was the switch.  Pulling/reinstalling the connector fixes it by forcing the contacts around, basically cleaning them a bit.  It'll work 'till it don't.  The good part is that when it fails again it won't bother you at all 'till you get hit, pulled over, or have to go for inspection again.  It's a cheap part, a normal person would just replace it, I look forward to the next conversation about its failure.

[RXX]

On 7/9/2022 at 10:15 AM, superhawk996 said:

 The good part is that when it fails again it won't bother you at all 'till you get hit, pulled over, or have to go for inspection again.  It's a cheap part, a normal person would just replace it, I look forward to the next conversation about its failure.

 

What is this inspection that you speak of?

[superhawk996]

On 7/16/2022 at 7:29 PM, RXX said:

 

What is this inspection that you speak of?

I assume his state has vehicle inspections since he spoke of it.  We don't, except in special cases like resurrecting a salvage.

[superhawk996]

Reminds me of the inspection when I did my last Ducati.  It was in the pickup and I asked the guy if I needed to unload it for the brake test.  "Did you test ride it?" Yup.  "You're still alive so the brakes work."  He barely paid attention while I manipulated the lights and forgot to ask if the horn worked.  The bike was in showroom condition, mighta helped.  Bike inspections are only done at bike shops and these guys looked to be enthusiasts so they might pass damn near anything to hook a brotha up.  From there I had to go to DMV for a VIN check.  The guy was too fat to get up into the massive base Tacoma that was squatted inches from the ground so I read the frame and engine numbers to him.  It was hard to read the engine number so I read it off the paper while holding the fairing back to make it look legit.  I had verified both before buying it.

[RXX]

7 hours ago, superhawk996 said:

I assume his state has vehicle inspections since he spoke of it.  We don't, except in special cases like resurrecting a salvage.

 

Right. I was just poking a brother from a northern state. We don’t have them in Tennessee (maybe Nashvile and Memphis). I still have the VA sticker on my bird I bought from him.

[Zero Knievel]

12 hours ago, RXX said:

Right. I was just poking a brother from a northern state. We don’t have them in Tennessee (maybe Nashvile and Memphis). I still have the VA sticker on my bird I bought from him.

I used some silicone lube on the fork after removing the old one, you should have an easier time peeling it off.