electrical issues ( brake lights)

[danm3275]

After getting my transmission serviced on my 1974 6cyl scout, I noticed the reverse lights didnt work. The shop checked and said they couldnt find anything and maybe it was the bulbs (?) so I said forget it, lesson learned, and I'd check the reverse switch later on myself.

Fast forward to a few days later, my brake lights wont come on.
I need my brakes more than reverse, so I started checking/hunting.
All wires and fuses look good, grounds look good, and for good measure I replaced the blinker relay and the brake switch, in my search, but still no dice.

Am i missing a relay, ect somewhere? I checked my repair manual and I can't seem to hunt it down.
Hopefully someone knows a million times more than me (no need to hope on that one actually, haha) and can shed some light on this.
Thanks!

[Randy Z.]

If you lost two functions on both sides, check your bulkhead connectors and insure that the grounds don't just look good.

[scoutboy74]

Manual or auto trans? Could make a difference. The TF 727 auto incorporates a a 3 prong neutral start switch threaded into the driver side of the case above the pan. One of the pins completes the circuit for reverse light actuation when R is selected. If manual, there will be a two prong pin (I don't know the exact location) which serves the same function.
Are the four-way flashers and directionals working fore and aft?
There is a two-terminal brake light switch under the dash near the top of the brake pedal arm which opens to complete the brake light circuit when the pedal is depressed.

[danm3275]

it's an auto. I checked my grounds and cleaned them, replaced the flasher and hazard relay, bulbs and checked all the bulkhead connectors.
( I finally fixed my issue with my fender lights and my horn while doing all this so at least things are getting better)
But still no brake lights or hazards. I looked underneath and saw the wires from the tranny switch are sandwiched in the gear selector cable, so that would explain my reverse lights I think.
Is there something else I'm missing with the brake lights? I'm running out of things to search ( if thats possible on a scout)

[Eric VanBuren]

The SII uses combined turn/brake lights so do the turn signals function in the rear? If so the wiring is good between the turn signal switch and the rear of the truck. Then check the brake sw and make sure that you have power on 1 side all the time and power on the other side when the pedal is depressed. If you have turn signals that work out back and the brake light sw is sending power to the turn signal switch then your turn signal switch is bad or there is a wiring problem between the brake and TS switches.

[scoutboy74]

What a botch job by the trans shop! Not only could that poor routing be contributing to your reverse lights failure, but it could also cause problems with shifter linkage function to the point of being a safety issue.

Originally Posted by danm3275

it's an auto. I checked my grounds and cleaned them, replaced the flasher and hazard relay, bulbs and checked all the bulkhead connectors.
( I finally fixed my issue with my fender lights and my horn while doing all this so at least things are getting better)
But still no brake lights or hazards. I looked underneath and saw the wires from the tranny switch are sandwiched in the gear selector cable, so that would explain my reverse lights I think.
Is there something else I'm missing with the brake lights? I'm running out of things to search ( if thats possible on a scout)

[danm3275]

The turn signals work out back so it has to be something up front. I'll check the brake switch voltage, I just put in a new one, so it cant be the switch.
Anything else I might be missing?

And yeah, I'm pretty annoyed about the job the tranny shop did, but thats what happens when someone doesnt care as much for your car as you do.
(I'm not even mentioning them telling me the tranny will need a complete overhaul in another 5-10k miles or the 800 plus price tag.)
Definitely lesson learned.

[danm3275]

Fixed the reverse light switch. Still no brake lights.
In this amazing neverending journey, I've fixed my horn, fender lights, reverse lights, basically all the things I was least concerned with.

But still no brake lights. Power is getting to the sockets because I have signals, but nothing in terms of brakelights.

So far the hazards dont work, the front signals blink together if the left side is selected, but they wont blink up front if the right side is selected, and the many mentioned brakelights.
Are these all related? Am I looking in the wrong place? Grounds are all good on the front parking lights.

[Eric VanBuren]

Things are pretty much pointing to the same thing and that is the turn signal sw. There are 3 separate power feeds to the TS sw. The brake light feed through the BL sw, the hazard through the hazard flasher, and the TS through the TS flasher. You need to check for power to and from the hazard flasher.

The issue with the front lights could be a short between the 2 wires or it could be the sw. How do the TS indicators react the same as the lights or as they should? How do the lights react when you put the hazard on and step on the brake?

[danm3275]

so far, the hazards dont work at all. The signals only work independently in the back and I get a steady blink on the instrument cluster on the right side, no blink on the left side of the cluster, but they work out back.
When I click on the hazard switch and hit signal to either side I get nothing also. But no hazards and I hit the signals and they work.
I'll have to check the turn signal switch power feeds ( hoping I dont need a new one, Napa has the signal fix kit for 25.00 and a new one is around 65.00)

Would a broken switch affect the brake lights the way they seem to be affected?