Electrical issue

I have a 98 tahoe 2wd. It has an electrical issue i can't seem to find. My right turn signal does not flash and my brake lights stay on when the key is on. I have replaced the brake light switch, flasher and even the rear brake light assemblies. What makes it more strange is that i can shut the truck off and remove the key and the truck will not shut off until i release the brake pedal. Could this possibly be the ignition? I don't want to just keep throwing parts at it. Any help would be appreciated

Bad keyswitch.

Ok, so i finally got my new parts in. Changed the tumbler and ignition wiring. Same issue, brake lights are still on and right turn signal does not work, interior buzzer sounds when brakes are applied. Any other ideas?

Did this start all of a sudden, you buy it like that, and is there hacked up wiring

Started all at once. Wiring is good, no hacked up splices or frays, still looks factory. I have had the truck almost 3 years

Anyone? Beuller?

I need to look at some diagrams to give you a better idea. But it's probably gonna be a few days before I can

Still haven't come up with a solution. Anyone have any ideas?

Taking a stab at it, when you hit the brakes voltage goes through the brake light switch (white wire, circuit #17) to the turn signal assembly. From there it goes to the brake lamps.

But, it looks like the turn/hazard flasher also feeds this circuit (purple wire, 1697). Pull the flasher from the convenience center and see if the brake lights go out.

ETrail Tahoe said:

my brake lights stay on when the key is on.... I can shut the truck off and remove the key and the truck will not shut off until i release the brake pedal

Click to expand...

Somehow you've got power finding its way between the switched circuits (i.e., those controlled by the IGN) and the circuit energized by the brake light switch.

For example, as you report, with the brake light switch ON (brake pedal depressed), the power downstream from the brake light switch is finding its way into the switched IGN circuit.

Similarly, with the IGN switched ON, power is finding its way into the wiring downstream from the brake light switch.

So, the first question is: Where do these to circuits have a connection in common? My guess is the answer has something to do with the lighting circuit and, in particular...

- a filament that's illuminated when the IGN switch is ON, and...

- another filament that's illuminated when the brake pedal switch is ON, and

- these two filaments share a common ground that's corroded or, shall we say, broken and not actually grounded.

- these two filaments may be in separate bulbs, or may be in the same bulb... this is TBD. Read on...


The next question might be: Why is this happening? As I mentioned above, my guess is there's a ground that's bad. I could be wrong.

You mentioned specifically that the right turn signal doesn't flash. This may (or may not) be a big clue.

I'll let you mull this over. Meanwhile I'll look at the schematics and see if I can figure out the problem.