My first problem, (electrical)

[tast101]

Ok, after I installed my tail lights a friend told me my brake lights weren't working. So I think a fuse is blown, since it happens to everyone when they first install the leds tails. Well all the fuses are ok. I test the voltage up at the fuse box 11-12 volts. I test the voltage at the socket and the metal tab for the running lights gets 11-12 volts, then metal tab for the brake lights gets .11 volts. Fuses isn't blow and the third brake light does work. I'm not sure what could be causing the voltage to drop back at the light socket. And this is for both the left and right light. It's not the LED light but the amount of power going back. Also what I noticed my cruise control isn't working, Not sure if this could be causing it?

 

[greengumby]

replacing the bulbs with LEDs disables the cruise control, I have read on where other people had to use resisters in conjunction to the leds. gotta look for those posts...I have also saw people on where they just plug in....did you pull out the leds and put back the oem light to make sure everything is back to normal?

 

[01lt_hoe]

aw sh@t, let me go check my cruise control and brake lights... if theres a problem with either, the leds have to go...I love the look of them, but I can't have them screwing up my truck....

 

[tast101]

aw sh@t, let me go check my cruise control and brake lights... if theres a problem with either, the leds have to go...I love the look of them, but I can't have them screwing up my truck....

I know I feel ya. :nonod:

 

[Old Goat]

replacing the bulbs with LEDs disables the cruise control, I have read on where other people had to use resisters in conjunction to the leds.

Not true.
They work just fine. No problems with cruise.

 

[tast101]

I think I'm just having an electrical issue.

 

[01lt_hoe]

just checked my cruise, & brake lights, and everything is fine....

 

[tast101]

just checked my cruise, & brake lights, and everything is fine....

I think its just my kon. I'm not getting enough voltage back there to power my lights for some reason.

 

[Old Goat]

I think you should check your grounds. Remember, they are part of the circuit too.

 

[Rivieraracing]

Hate to say it but be sure to check every fuse on your truck, not just the ones that are labeled for the brakes or CC. Every so often I would plug in my trailers wiring plug into the truck and would lose my power brakes for my trailer( at least the automatic portion of the brakes). As a side effect of that I would also blow different fuses each time it would happen and none of them were directly related to the problem (at least the labeling of the blown fuse). Can't remember which ones they were but it was strange everytime, it would take the dealership a ton of time each time to diagnose it and eventually they started yanking EVERY fuse and checking seeing if it was good or not, as soon as they found a blown one and replaced it, I was good to go till it would happen again (found it to be a crappy trailer plug that could go into the socket slightly out of alignment and short out a circuit before it would correct itself and plug all the way in correctly).

 

[tast101]

Well I've checked every fuse in the engine bay and the ones on the side of the dash. The other day we did find a accessory fuse that was blown but it didn't fix the prob. Checked the ground side of the socket too. any other ideas?

Hate to say it but be sure to check every fuse on your truck, not just the ones that are labeled for the brakes or CC. Every so often I would plug in my trailers wiring plug into the truck and would lose my power brakes for my trailer( at least the automatic portion of the brakes). As a side effect of that I would also blow different fuses each time it would happen and none of them were directly related to the problem (at least the labeling of the blown fuse). Can't remember which ones they were but it was strange everytime, it would take the dealership a ton of time each time to diagnose it and eventually they started yanking EVERY fuse and checking seeing if it was good or not, as soon as they found a blown one and replaced it, I was good to go till it would happen again (found it to be a crappy trailer plug that could go into the socket slightly out of alignment and short out a circuit before it would correct itself and plug all the way in correctly).

How much did they charge you to diagnose it?

 

[tast101]

It's a lot easier to diagnose with a scan tool. Everything is basically tied into the PCM, BCM, etc via some sort of databus, CAN, LAN, etc on newer vehicles, which is how the different components communicate.
These asre the related parts for the cruise control system:
The powertrain control module (PCM)
The On/Off switch
The Resume/Accel switch
The Set/Coast switch
The torque converter clutch (TCC)/brake switch
The stop lamp switch
The throttle actuator control (TAC) module
The vehicle speed sensor

There are only a few basic things you can check for w/o a scan tool.
1. Check to make sure your brakelamps are functioning 100% properly. The cruise control system takes into consideration the state of the brakelight switch, whether or not it is opened or closed in order to send the correct signal to the PCM.
2. Remove the fuse and re-insert. Sometimes a non-conductive film will build-up between the contacts and cause intermittent problems from low voltage.

A lot of times the on/off switch or resume/accel portion goes bad before anything.

There is also a TSB (Bulletin No.: 03-06-04-012A) concerning the integrity of connectors which 06 and prior light duty trucks are included. Among the related symptoms are intermittent/inoperative cruise control.

Been doing some reading on here and gmfullsize, one fix may be the switch on the brake pedal, but I don't think that's it for me because the 3rd brake light still comes on.

 

[OmarR]

replacing the bulbs with LEDs disables the cruise control, I have read on where other people had to use resisters in conjunction to the leds.

Most of the newer LED taillights have load equalizers built in to prevent this. A quick test for this would be to simply turn on your turn signals (left or right). If the dash indicator flashes fast like when a bulb is burnt out, then then the tail light needs a load equalizer.

Tast101:

I have your tail lights without any problems. Your load equalizer is that little black box in the middle of your tailight when looking at it from the inside.

Your brake lights start wtith a 25 amp fuse in the engine compartment, then the left and right tail light split off from the third tail light in the driver fuse panel. Since your third brake light is working, then your underhood fuse is working. Double check your vehicle stop tail lamp fuse. It is in the driver fuse panel, lower left, and it is a 15A fuse. Even if it tests good, change it out anyways just to make sure.

Also, are you sure you plugged in the LED's correctly? I am not trying to be a smartass, but those plugs have the ability to go in either way, BUT there is a correct way to plug them in. The two black wires (ground) on the LED plug have to match the black wire (ground) on the car's socket. This may be easy to overlook. Do your tail lights light up at all when you turn on your parking lights? If they do, then you at least have them plugged in correctly.

Lastly, gumby gives good advice when suggesting that you also try your stock tail lamps again. Maybe your LED's gave out? (I doubt this happened)

Good luck!

 

[tast101]

Most of the newer LED taillights have load equalizers built in to prevent this. A quick test for this would be to simply turn on your turn signals (left or right). If the dash indicator flashes fast like when a bulb is burnt out, then then the tail light needs a load equalizer.

Tast101:

I have your tail lights without any problems. Your load equalizer is that little black box in the middle of your tailight when looking at it from the inside.

Your brake lights start wtith a 25 amp fuse in the engine compartment, then the left and right tail light split off from the third tail light in the driver fuse panel. Since your third brake light is working, then your underhood fuse is working. Double check your vehicle stop tail lamp fuse. It is in the driver fuse panel, lower left, and it is a 15A fuse. Even if it tests good, change it out anyways just to make sure.

Also, are you sure you plugged in the LED's correctly? I am not trying to be a smartass, but those plugs have the ability to go in either way, BUT there is a correct way to plug them in. The two black wires (ground) on the LED plug have to match the black wire (ground) on the car's socket. This may be easy to overlook. Do your tail lights light up at all when you turn on your parking lights? If they do, then you at least have them plugged in correctly.

Lastly, gumby gives good advice when suggesting that you also try your stock tail lamps again. Maybe your LED's gave out? (I doubt this happened)

Good luck!

My running lights work, its just when I brake they don't light up any brighter, or say the running lights aren't on and I hit the brake they don't light up. Yea I have the black wires lined up negative to negative.

 

[OmarR]

Replace the 15A vehicle stop fuse in driver side panel.

With someone depressing the brake, test the brake socket (metal tab) on the car. Do you get 12V? I know you posted earlier that you got .11 volts, but you didnt mention whether you had replaced the 15A fuse and if you had someone actually stepping on the brake when you were testing the socket.

 

[tast101]

I'll try replacing the fuse, I braced something on the brake, it was depressed because the 3rd light was on.

 

[greengumby]

Did you put back the oem lenses to verify that you have a working circuit? another way to do it is that leave an oem in and install a led light after you have verified the conductivity and operation of the circuit. It may be the obvious you may have received a bad batch of leds

 

[tast101]

Nah the bulb doesn't work either. I guess I'm just take it to the dealer and let them trouble shoot it.

 

[greengumby]

:wow:

 

[tast101]

Whelp, twas the brake light switch. It was low on halogen fluid. Didn't have enough to power the LEDS.