[Bushranger]

2007 Colorado Ls The driver's side brake light is not working. Changed the bulb, still no light.
I have schematics and can see that it is the same Lt. blue wire that powers the passenger side stop lamp, so the problem would seem to be somewhere between the driver's side stop lamp and something labeled "S403" on the schematics. Would someone please tell me what "S403" is and where it is located?

 

[cart7881]

Splice 403 is located in the Chassis harness, approximately 14 cm (5.6 in) from the main harness on the breakout to C401 and C402. C401 would be the connector for the Left tail light and C402 would be for the Right tail light. The splice will be in the harness about 5-1/2 inches from where the wires for the two connectors exit the chassis harness.

If you have the towing option there may be a problem with that harness. If you don't find anything at the splice and you do have the tow package, follow that harness forward to where you see two connectors. Disconnect the two connectors from the chassis harness. Then connect the two chassis harness connectors together. That will eliminate the tow harness from the equation. You must reconnect the two chassis connectors together in order to get lights on both sides. No tow option---disregard.

 

[Bushranger]

Splice 403 is located in the Chassis harness, approximately 14 cm (5.6 in) from the main harness on the breakout to C401 and C402.

Where is/are those splices in regard to the structure of the truck? For instance, are those splices in the cab? In front of the driver's side rear wheel on the frame? The schematics and your explanation do not indicate physical location in regard to the external structures of the truck. At 74 years of age, crawling around on my knees looking for things is problematic.
Note: my truck does have the towing connector plug.

 

[White016]

Where is/are those splices in regard to the structure of the truck? For instance, are those splices in the cab? In front of the driver's side rear wheel on the frame? The schematics and your explanation do not indicate physical location in regard to the external structures of the truck. At 74 years of age, crawling around on my knees looking for things is problematic.
Note: my truck does have the towing connector plug.

I don't have time right now to look it up but....tail lights and brake lights are not the same. Also, does this truck have separate turn signals/brake lights? I can't remember, but if not those two aren't going to be tied together. If they are the same/tied together I'm sure it will be at the back of the truck. No need to run two wires for nothing. Right?

 

[Bushranger]

I don't have time right now to look it up but....tail lights and brake lights are not the same. Also, does this truck have separate turn signals/brake lights? I can't remember, but if not those two aren't going to be tied together. If they are the same/tied together I'm sure it will be at the back of the truck. No need to run two wires for nothing. Right?

Oh! Now I know! :roll: You have saved me time on my 74 year-old knees looking under the truck. Seriously...did you think an answer such as that would be any help? If you do not know, please do not answer...it benefits no one. I need to know where the splices are...it does me no good to look under the dash, behind the driver's seat, etc. if they are not there. I am not twenty years old anymore and do not have the physical ability to crawl around looking for things. By the way, the turn signals and brake lights are separate.

 

[cart7881]

The splice that you are looking for is located at the left rear of the truck, in the chassis harness that runs from the front of the truck to the rear. Look for the wiring coming from the left rear tail light assembly, follow it to where it exits from the chassis harness. You will have to open the harness covering the wires to find the splice. The Manual is not specific on whether the splice is forward or aft of the point where the tail light wire exits.

There haven't been any reports of problems with that splice so before opening up that can of worms disconnect the tow harness and see if the problem clears up.

1. Locate the plug, at the bumper, where the trailer wiring plugs in.
2. Find the wire harness, forward of the bumper, that the tow connector is attached to.
3. Follow that harness forward and to the left (driver's) side until you find the two connectors for the tow harness.
4. Disconnect both of the connectors from the chassis harness.
5. Now take the two chassis harness connectors (one is male and the other is female) and connect them together.
6 Check and see if the light is still inop.

I'm 76 and still maintain several vehicles.

 

[White016]

Oh! Now I know! :roll: You have saved me time on my 74 year-old knees looking under the truck. Seriously...did you think an answer such as that would be any help? If you do not know, please do not answer...it benefits no one. I need to know where the splices are...it does me no good to look under the dash, behind the driver's seat, etc. if they are not there. I am not twenty years old anymore and do not have the physical ability to crawl around looking for things. By the way, the turn signals and brake lights are separate.

Sorry, I told you if they are separate from tail lights it would be at the back of the truck. At least I kept your old knees from under the dash and under the cab carpet right? Sheesh.

:serious:0