Center Dome Light and Cargo Light Don't Work

[iDog]

Hi all,

I just bought a 1995 Cheyenne C2500 and was hoping to get some assistance with an electrical issue I am having. I looked at some other post on this site and others and couldn't quite seem to find my particular issue.

My center dome light does not work at all, either when I roll the wheel up to activate it or when I open a door. The lights on the floor DO come on with the open doors and with the switch so they seem to behaving normal. From what I understand they are on the same circuit. The other interesting thing is the push button (map?) lights on each side of the dome light work fine. So "power" is getting to there it seems. My cargo light in the back doesn't seem to work either. Fuse is fine. High Brake Light works fine also

I tried swapping bulbs in question and still nothing. Not sure where to start or if two failures are related.

Any leads? Could it be the piece that goes under the dome housing? Some kind of relay? Bad wire spot? Bad headlight switch somehow?

Would like to hone in a bit before throwing too much money at it. I could live with it but I would really like to get these fixed.

 

[Drunkcanuk]

Hi all,

I just bought a 1995 Cheyenne C2500 and was hoping to get some assistance with an electrical issue I am having. I looked at some other post on this site and others and couldn't quite seem to find my particular issue.

My center dome light does not work at all, either when I roll the wheel up to activate it or when I open a door. The lights on the floor DO come on with the open doors and with the switch so they seem to behaving normal. From what I understand they are on the same circuit. The other interesting thing is the push button (map?) lights on each side of the dome light work fine. So "power" is getting to there it seems. My cargo light in the back doesn't seem to work either. Fuse is fine. High Brake Light works fine also

I tried swapping bulbs in question and still nothing. Not sure where to start or if two failures are related.

Any leads? Could it be the piece that goes under the dome housing? Some kind of relay? Bad wire spot? Bad headlight switch somehow?

Would like to hone in a bit before throwing too much money at it. I could live with it but I would really like to get these fixed.

Did you pull the bulbs and use a multimeter to see if the bulbs are actually getting the 12v in the socket?

 

[iDog]

Did you pull the bulbs and use a multimeter to see if the bulbs are actually getting the 12v in the socket?

I attempted to but my multimeter is malfunctioning I think it needs new leads. But the lights next to it do work and I only see the one orange wire and one white wire coming in.

 

[KansasOBS]

There are some other things to check with a meter as already mentioned, etc. But I will say the wires to this stuff are the ones that run along the lower door sill, and up into the back. Could be some damaged wires under there.

 

[AK49BWL]

If the map lights are getting power, the dome light is as well. The map lights are grounded at the lights housing. And yes all the dome lights are on the same circuit so your switch is working fine. The dome lights are ground-switched - the cargo light is also on that same ground despite being powered by the cargo light switch, so even if you have the cargo light switch on, if the dome lights are off, so will the cargo light be off. If neither work, the problem is going to be in that white wire that runs from the cargo/dome light to the switch via the driver door sill. The wires in the door sill are known for chafing, so personally that's where I'd start looking.

Something you can test without pulling anything else apart (when you get a working multimeter) is whether you have continuity between the white wire at the dome light and ground when you turn the switch on - you should.

 

[iDog]

If the map lights are getting power, the dome light is as well. The map lights are grounded at the lights housing. And yes all the dome lights are on the same circuit so your switch is working fine. The dome lights are ground-switched - the cargo light is also on that same ground despite being powered by the cargo light switch, so even if you have the cargo light switch on, if the dome lights are off, so will the cargo light be off. If neither work, the problem is going to be in that white wire that runs from the cargo/dome light to the switch via the driver door sill. The wires in the door sill are known for chafing, so personally that's where I'd start looking.

Something you can test without pulling anything else apart (when you get a working multimeter) is whether you have continuity between the white wire at the dome light and ground when you turn the switch on - you should.

I will try that and report back. Could I test between the white wire and the metal area for the bolt for the housing ?

 

[AK49BWL]

That would work fine as that's where the map lights are grounded.

 

[iDog]

Ok I did a few test using a scrap wire and 2 multi meters.

On both multi meters the voltage on orange wire was about 12.6 when probed on fixture metal on orange wire and the truck body.

I tried continuity on both the wire itself and the the fixture and nothing.

I ran a jumper wire from the bare metal of the truck to the light fixture and it lights up.

So it seems that my issue is my white wire is not grounded. Any thoughts on next step?

 

[GoToGuy]

The OE service manuals are available here in a PDF download.

 

[AK49BWL]

Ok I did a few test using a scrap wire and 2 multi meters.

On both multi meters the voltage on orange wire was about 12.6 when probed on fixture metal on orange wire and the truck body.

I tried continuity on both the wire itself and the the fixture and nothing.

I ran a jumper wire from the bare metal of the truck to the light fixture and it lights up.

So it seems that my issue is my white wire is not grounded. Any thoughts on next step?

Next step is find the break lol. I'm betting on it being under the driver door sill, between there and the kick panel going up into the dash. No need to download and waste hours reading a service manual for a simple wire break that people have had experience with before.....