New fuse block installed... brake light questions....

[kaptnkaos]

Hey Guys...

Did a bunch of wirin' today.
I got the new custom fuse block I made a month or so ago installed today...
It works like the a champ.
The feed post on the left is hot all the time. It feeds 4 circuits
The feed post in the center is hot with the key. It feeds 6 circuits.
The small block on the bottom right is fed from the light switch rheostat.
I did that so I could fuse the dash lights and other gauges separately.

click on pic to enlarge
Now, I have several open circuit feeds in case I wanna add stuff, which I do.

Then, I moved on to the camper.
I posted a previous thread about my campin' trip and how I had fried the wires from the deep cycle battery and had no power inside the camper... and that none of the camper exterior lights worked.
Well, I went through all the circuits and got everything working except the right side brake light.
It was beginning to get dark when I stopped messing with it.
Just about the time I gave up, I realized that the right rear brake light wasn't working on the truck either...

Anyone got any ideas where I should start trouble shooting???
Would a bad ground on the truck light cause both lights to not work???
The tail light and turn signals work fine on that side...
so I am a little puzzled.

Any help would be appreciated...

Thanks again,
KaptnKA S

[oldschoolrods]

Well the brake and turn are on the same filament, so if you have turn signals on that side, check the stop light switch, by my 1967 print it looks like a red-black stripe wire that runs to the turn signal switch. I'd start by making sure all the connections are good there. Good luck.

[kaptnkaos]

Hey oldschoolrods...

I might be wrong... but I think the brake switch is either on or off and the left side brake light works, I'm not sure if either would work at all if it was the switch.
Both brake lights were working before...
now neither (the camper nor the truck) are working on the one side.
That's why I'm puzzled.
Some where I have a new in the box switch, I just have to find it...
it's better to rule it out than wonder about it.
I probably won't be able to mess with for a couple more days...
I am hoping to use it to go camping again this weekend.

KaptnKAOS

[seattle67]

Hey kaptn,
One thing that may help you trouble shoot this is to take it one step at a time. Figure out why the truck light isn't working and then once you have that fixed, look into the problem with the camper.

[kaptnkaos]

Yeah seattle67...

I'm sure if I figure out why the circuit isn't working on the truck, the camper problem will also be fixed.

I'm pretty sure it is the problem same that's causing both to not work, I'm just not sure where to start...
I want to rule the obvious... ground issues
I just did that on the truck a little while ago, because that ligt wasn't working. at all.
I disconnected the ground and clean up the contact surfaces really good and coated with dielectric grease before putting it back together...
I'm gonna dig out the wiring diagram and trace down wires to see if I can find out what's going on... Like I said earlier, I'll replace the brake light switch before doing anything else, but I doubt that's the problem
Thanks for the input...

KaptnKA S

[oldschoolrods]

i meant to type check the turn signal switch, sorry about that the brake lights get wired though there so when you press the brake with the turn signal on it will still flash.

sorry for the confusion

[kaptnkaos]

No worries oldschoolrods,

I just recently rebuilt the steering column when I did the PS upgrade a couple of months ago, so the TSS is brand new... it doesn't mean it cant be bad.
All of the lights worked on the truck before I used the camper.
which leads me to believe that they are related.

KaptnKA S

[seattle67]

kaptn,
I agree with you, I don't think its the brake switch. I think oldschoolrods is on the right track, one of the first things I try to determine, when trouble shooting on a ship, is what in that circuit was most recently worked on. That is the area of suspect.

The path, as best I can tell, is as follows:

From your brake light switch its a red wire with a black stripe, this goes to a connector and turns into a green wire with a red stripe. That wire goes into your turn signal switch and is what energizes both brake lights. Its in your turn signal switch that this signal gets split for left and right. Leaving the turn signal switch is an orange wire with a blue stripe (right side light) and a green wire with an orange stripe (left side light). We will follow the orange wire with the blue stripe. That wire goes to a connector and turns into a green wire. It looks as though the green wire goes through 4 separate connectors before it gets to the brake light itself, any one of which could be the point of failure.

Wedge something in to energize your brake light switch. Then, using your meter, put one lead to ground, then start from your brake light switch and just follow the path. The point that you don't have power is your point of failure. Though always keep in mind that there may be more then one point of failure.

One thing, if your right blinker works, then the problem with the right brake light almost has to be in your turn signal switch. (This is assuming that your left brake light works)

Good luck!

[rjewkes]

perhaps you snagged the wire under the truck on somethng?

[kaptnkaos]

Yeah...

Thanks guys...
I was just looking at the schematic and trying to figure out the wire routing.

Is there a way to check the TSS to see if the thing is working right without removing the darn thing ???
It is only about 2 months old... I ordered it new from NPD.
And have only driven the truck twice since installing it.
I know both brakes lights were working after I installed the new switch.
Since the turn signal and brake light are fed buy the same wire, I don't see how it could be any of the connections between the cab and the light, because the turn signal and tailight both work on that side.
Since the left brake light works, it isn't the brake light switch.
I'm beginning to come to the same conclusion about it being the TSS since almost everything else has been ruled out...
I hope not, 'cause I really don't wanna have to replace it again, but I can't see where it could be anything else at this point.

Arrrrrggggg....

KaptnKA S

[seattle67]

Well, you have to figure the power going to the turn signal switch is good, so find the orange wire with the blue stripe that is going out from the tss. That wire should be hot if you push on the brake pedal or if you turn on the right blinker. If it does both those, then the tss isn't the problem.

[kaptnkaos]

Thanks Dan,

That's what I was thinkin', but it always dangerous when my thinkin' and electricity are used in the same sentence...

KaptnKA 8)S

[Thunderfoot]

I agree with Dan,
The problem sounds like it is in the Turn Signal Switch... Beings your right rear turn signal works, this means that the ground and wire itself are good, as it uses this same wire and (bulb filament) as oldschoolrods said above for both turn and brake...
The brake light switch is working as it is only a single wire from it to the TSS, then it splits out to both sides. The TSS has contacts on it that when you make a "Left turn" for example will disengage the left brake light connection so that the left light will blink... Sounds like this contact in the TSS is not making connection anymore for the right side, you may be able to pull the steering wheel off and look at the contact on the TSS and fix the problem... Or worst case is that the camper wiring being bad might have overloaded the contacts for this right side and it melted the TSS there.

Anyways... my is to pull the steering wheel off and take a look there at the TSS...

[kaptnkaos]

Hey guys,

I wanted to let ya all know that we all came to the proper conclusion...
It was the TSS...

I pulled the wheel and couldn't see anything wrong with it.
There were no burnt or broken wires, everything seemed fine.
There are two wires on the top of the cam...
Only one was hot with the brake pedal engaged.
I pulled the switch out enough to get a look at the bottom side...
Couldn't see anything wrong, I checked the contacts again and had power to both wires.
So I reinstalled the switch, wheel hub and steering wheel, checking the brake lights after each step.
Everything is working now as it should.
I even hooked up the backup lights...
If the brake lights go out again, I'll know where to start.

Thanks again...

KaptnKA S

[seattle67]

Good job kaptn! I'm thinking you're more electrically savvy then you like to admit