Reverse lights & Cab lights

[BSridenguy]

I have an 04 Silverado, 2dr WT model.. Manual.. So it has manual windows and manual door locks.. I'm looking to find where the wiring for the interior of the truck lands. . 2 Seperate problems with lights..

1. The dome light, and the door lights don't turn on for some reason when i open my door.. I checked all my fuses, and all are good( not sure where the dome light/interior light fuses all land but i looked at all my fuses in truck and engine compartment and they all look good). I checked the bulb for my dome light and its good. Problem is i'm not getting any power to the dome light. Before i tear everything apart, does anyone know where the interior light wires land and what color wires they are? Thanks in Advance...

2. I have power to the back up fuse when i put the truck is in reverse so i know the wires are good to the fuses.. When i put the truck in reverse though, my backup lights don't come on. . Same thing though, bulbs are good, but no power to the socket. . .

Now i worked on my truck the other day, replacing the clutch pedal. So do the reverse lights and dome light wires land somewhere by the clutch pedal?(i looked around for skinned wires and wires that looked stressed or pulled out of place, to no avail) Any help or ideas would be great. . Hopefully i don't have to tear everything under my dash out... If you know where the wires land or colors, that would be AWESOME. Thanks in advance

[tanz45]

Reverse light switch should be on the tranny.

Dome light....Dome over ride button stuck?

[sierraman]

it could be the dome light sensor in your latch/lock actuator.

[tanz45]

it could be the dome light sensor in your latch/lock actuator.

Can you manually turn the dome light on? What about when the passenger door is opened to go with this^^^^^^.

[sierraman]

yes you can still manually operate it. and yes it could be in could passenger side lock also

[GasGuzzler]

Need to know if you can turn the interior lights on with the thumb wheel. I thought the manual door trucks had dummy refectors in the doors with no lights.

The power wires to the interior lights are grey or grey/black. Grounds are black. The BCM supplies the power from connector C5 (6-way black) terminal E. From there power goes to relay block I/P and comes out at C3-L of the relay block. From there it goes to the dome lamp(s). From the lamp(s) it goes to ground G200 located on top of the dash behind the LH A-pillar interior molding.

[GasGuzzler]

There are 7 different interior light schematics so the door lights if equipped depend on teh Y-options on your SPID label in the glove box.

The reverse light circuit is kinda convoluted. The fuse is at the start of the circuit so it being OK doesn't tell us anything except you have no shorts (LOL). From the fuse the pink power wire 1st goes to the back up lamp switch then comes out there as a grey wire. The grey wire goes back to the underhood fuse panel but then back out without passing through a fuse. It comes out at UBEC connector C2 terminal A11 grey and goes to the BCM as an input. The bcm powers the reverse lights from BCM connector C5 (same as above) terminal F light green. From there it goes to the relay block I/P C1-A1 then on to the junction block rear lamps located under the rear. The outputs are C4-E light green and C2-F light green. They're in different connectors because each tail lamp has its own harness.

I would start at the rear lamp junction block as I have seen the connectors full of water and corrosion (usually on Suburbans).

[GasGuzzler]

If the rear lamp junction block connections look Ok I would pull the driver knee bolster and check the connections at the BCM since your two problem circuits are right next to each other in the same BCM connector.

You can hot wire power at the disconnected BCM connector C5 and see if the lights come on. This would rule out the wiring, connections, sockets, bulbs, etc.

The reverse lights ground at G401 near the spare tire hoist.

[BSridenguy]

Thanks guys for all the Quick replys. .

As for the dome overide switch, no it does no turn on the lights. . And when you open the passenger door, the dome light does not come on either.. And yes when i said interior lights, i meant just the interior lights. the ones in the doors are just reflectors.... And NO the dome light does not turn on the with the actuator wheel all the way up.

"If the rear lamp junction block connections look Ok I would pull the driver knee bolster and check the connections at the BCM since your two problem circuits are right next to each other in the same BCM connector."

Gas Guzzler, where is this BCM? is this the one on the floorboard to the left of the clutch pedal? Sorry i'm not very good truck wiring and BCM's and stuff. . Even though i'm an electrician by Trade LOL..
Thanks for all the Replies guys

[GasGuzzler]

It's right under the steering column. Pull off the dash colored trim on the rear (facing driver) of the lower part of the dash. Two 7mm screws, one by the ebrake release, one closer to the middle of the truck. It's a black box about 6X6X1 with about 6 plugs, sometimes one in the bottom.

Check at the BCM for reverse lights INPUT voltage too. This can tell you if the switch on the trans is OK.