Cargo and Dome not working

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perky

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The cargo and dome lights haven't worked in the C20 since it's been parked in the garage, so I ordered new bulbs for them from LMC, and installed them hoping for the best, but no joy. Courtesy fuse looks good as its a glass fuse and it'd be easy to see. I've checked all the connections and can't see anything wrong, although the passenger door switch is rusty, but the drivers side is fine, and it still doesn't come on with the switch on the dash or opening either door. I'll post pictures of the fuses and connections, but I'm really hoping someone can help me out.
 
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RustyPile

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Visual inspection of a fuse does not always determine if it's good.. Either test it installed using a test light/DVM to probe each end of it for voltage. An alternate test involves removing it and checking it for continuity.

That orange wire starts at the fuse box and "meanders" all over the place, goes to each dome/courtesy light bulb and cargo light. The white wire does just about the same thing -- goes to each light bulb, each door switch, and the headlight switch.. The white wire is the ground path and will show voltage unless one of the doors are open or the headlight switch is turned fully counterclockwise.. The cargo lamp is controlled by a separate switch that switches the white wire to the cargo light to ground. Check the orange wire for voltage, given a good fuse, it is "always hot".. If voltage is present, using a suitable jumper wire, ground the white wire.. Lights should come on..

If lights don't come on, check each bulb socket for voltage on the orange wire. Should have voltage on each one.. If not, check for voltage at each and every plug along it's length.. Repair the open/bad connection. On the bulbs that do have voltage, ground the white wire. Repair the open circuit in the white wire of those that don't then come on..

Having said all this, my money is on a bad fuse......
 

RustyPile

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Do they share a fuse or a ground?
They all share the same fuse, but none of them are grounded directly.. The white wire provides a ground path to the door switches and headlight switch, which completes the ground when switched.
 

75gmck25

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The wires run under the kick plate on the drivers side door. Insulation got very brittle on mine and I had to replace that section of wire.
 

Jgonick

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Does the courtesy light work? The courtesy uses an orange wire that runs to the light switch then the fuse box (the ctsy fuse). The dome light uses a different orange wire to feed it. -it is usually plugged into the front top of the fuse box (by batt )

Like mentioned earlier- both the courtesy light and dome use the same white wires to ground. ALL the white wires meet up at the courtesy lamp. The dome light white wire is spliced into the driver door jamb switch white wire running to the courtesy light. (usually close to the fuse box on the left side. It ought to be where you see the orange and white wire together headed downward that heads to the dome light.)
 
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The wires run under the kick plate on the drivers side door. Insulation got very brittle on mine and I had to replace that section of wire.

Yep. I've had to replace that section of wire several times on trucks. Even if the wires look ok, if they are very stiff and don't like to flex, the wire strands have probably turned to little more than green corrosion.
 

Jgonick

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What is this orange wire that is unplugged? That might actually be the dome light feed. (should feed clock and dome)
-should plug in at blue arrow
You must be registered for see images attach
 
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mlsceo

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My dome light wasn't working. I took out the switches in the door frame and lightly sanded them, fixed up both sides and the light works great. Make sure you push the spring loaded contacts in and out in order to clean them up at the point of contact.
 

perky

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Visual inspection of a fuse does not always determine if it's good.. Either test it installed using a test light/DVM to probe each end of it for voltage. An alternate test involves removing it and checking it for continuity.

That orange wire starts at the fuse box and "meanders" all over the place, goes to each dome/courtesy light bulb and cargo light. The white wire does just about the same thing -- goes to each light bulb, each door switch, and the headlight switch.. The white wire is the ground path and will show voltage unless one of the doors are open or the headlight switch is turned fully counterclockwise.. The cargo lamp is controlled by a separate switch that switches the white wire to the cargo light to ground. Check the orange wire for voltage, given a good fuse, it is "always hot".. If voltage is present, using a suitable jumper wire, ground the white wire.. Lights should come on..

If lights don't come on, check each bulb socket for voltage on the orange wire. Should have voltage on each one.. If not, check for voltage at each and every plug along it's length.. Repair the open/bad connection. On the bulbs that do have voltage, ground the white wire. Repair the open circuit in the white wire of those that don't then come on..

Having said all this, my money is on a bad fuse......
Okay, I'll check the fuse first, then follow up with your other suggestions. Thank you.
 

perky

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Does the courtesy light work? The courtesy uses an orange wire that runs to the light switch then the fuse box (the ctsy fuse). The dome light uses a different orange wire to feed it. -it is usually plugged into the front top of the fuse box (by batt )

Like mentioned earlier- both the courtesy light and dome use the same white wires to ground. ALL the white wires meet up at the courtesy lamp. The dome light white wire is spliced into the driver door jamb switch white wire running to the courtesy light. (usually close to the fuse box on the left side. It ought to be where you see the orange and white wire together headed downward that heads to the dome light.)
Courtesy lamp is also inop, but I didn't even realize I had one when I ordered the bulbs, so there is a very good chance it has a dead bulb amoung other things. I'll check the connections on the box and see what happens.
 

perky

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What is this orange wire that is unplugged? That might actually be the dome light feed. (should feed clock and dome)
-should plug in at blue arrow
You must be registered for see images attach
You are on to something there I think. That was initially unplugged from itself under the dash, and I couldn't find anywhere for it to connect other than that, so I will definetly hook it up right. The clock has never worked either, so it could be as simple as that. Thank you.
 

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