Fleetwood Heritage 600 CB 2002 – No Interior Lights (All Other Systems Working)

[Beachball]

Hi gizickim Welcome to the forum sorry I cannot help but i think you will get plenty of advice on here

 

[gizickim]

The question is whether they could potentially be the issue preventing all the lights from working. I could, for example, swap them to see if that helps, but I am not sure if this would make any difference.

 

[IanB1485]

The relays look in good condition, the contacts aren't damaged and there no evidence of arcing ( metallic black/grey deposit on plastic case) also the coils have no discolouration which would indicate overheating ( which would cause the wire in the coil to break).The bottom relay is probably the isolate relay ( cuts off the 12V system when the car is plugged in).So if the rest of the 12V systems are working( orange wires have +12V on them) then that relay contacts are OK.
Tracing out the green (with brown markers) wires is the next thing to check, do they have +12V on the them . A convenient 0V in the fuse box is the black wire on the bottom relay.

 

[gizickim]

The relays look in good condition, the contacts aren't damaged and there no evidence of arcing ( metallic black/grey deposit on plastic case) also the coils have no discolouration which would indicate overheating ( which would cause the wire in the coil to break).The bottom relay is probably the isolate relay ( cuts off the 12V system when the car is plugged in).So if the rest of the 12V systems are working( orange wires have +12V on them) then that relay contacts are OK.
Tracing out the green (with brown markers) wires is the next thing to check, do they have +12V on the them . A convenient 0V in the fuse box is the black wire on the bottom relay.

Thank you. I will check it out later today. I have a wire extension for my multimeter, so I will make sure to check whether it is the ground or the V+ that is discontinuous.

 

[Dustydog]

You will see on another post I had trouble with my interior 12v lights .
Testing the circuit section by section ,it was the 12 v master switch that had failed. A replacement fixed it.

 

[gizickim]

You will see on another post I had trouble with my interior 12v lights .
Testing the circuit section by section ,it was the 12 v master switch that had failed. A replacement fixed it.
View attachment 9721View attachment 9722

Is this the one located by the entrance of the the van ?

 

[gizickim]

Another update after a full afternoon of testing.


When I connect my multimeter’s negative probe to a separate known good earth (chassis or battery negative), I’m getting +12 V on both terminals of the bulb connector. That means the positive feed is fine, but the negative/earth return isn’t actually connected — it’s floating at the same potential as the live side.


So the fault definitely appears to be on the earth side of the lighting circuit rather than the power feed.