There is another test you can do at the REM multi connector.
With the ignition on, but all the lights off, every wire that is connected to a lamp should read live on a meter.
These are all the wires with stripes, on pins 1 to 10 and pin 12.
This live feed is via each of the lamps.
If any are not live then the problem is with the lamp, lamp clusters or the wires to them.
If they are all live then the problem is forward of this in the REM, the wires from the instrement cluster, the instrement cluster it self, the wires to the switch or the switch.

It would also be a good idea to inspect the wires that go to the trunk lid where they flex, as these have been known to fail then short out.

My next step would probably be to test the various resistances from the switch at the connector in the steering column using the wireing diagram as a guide to what each one should be.

Mellow

 

Hello kr98664. Yeah, i think possibly its time to roll the dice with a replacement REM. I've previously searched and found replacement REM's on eBay that match my model number.

Hello M-e-l-l-o-w. I've previously done tests on the wiring/connectors and they all appear to be powered-up based on the electrical drawing wiring layout. So I think the lamp clusters are OK. I've installed two (2) used replacement light switches with no change or resolution in problem. Assuming at least one (1) of the replacement switches was/is good, then so would the resistances from the switch at the connector in the steering column. I've visually-inspected all the wiring to and from the REM and found nuthin', I'll check the wiring going to the trunk lid again, but the problem would appear to be with the REM or Instrument Cluster. I think Im gonna just roll the dice with a "used" replacement REM. .

 

I swear I read somewhere that because of way these circuits are designed, you shouldnt use a test light because it loads it... use only a high impedance dmm.

So since the turn signals are direct wired I would think that you’ve got a problem and your turn signal switch if I have time I’ll look at the schematic. Seems weird that the module could cross circuit somehow but I don’t know what’s inside the REM

I had an Oldsmobile that had cruise control turn signals and lights in the same stock switch. Over time and usage little bits of metal would come off the contacts inside the switch and get stuck in the dielectric grease and create shortsThat would cause your lights to blink on and off and there was nothing you could do about it to stop the blink because the short was in the grease and moving the switch didn’t change anything. A temporary fix was get electrical contact cleaner and spray it into the body of the switch where the contacts were located. You could see where the contacts were because on the outside plastic body of the switch they were a little metal parts with a hole in the center of it and those were the contacts so you spray in each front of those and just flush it out in the light switch stop flashing for a while. You might have a similar situation here where something is backfeeding into the headlights or from the headlights

 

OK I just refresh myself on all of your symptoms and I see that you’ve already replaced the columns switch so that tends to rule that component out although it could be some strange coincidence that the second switch is also bad but I doubt it. I noticed in the schematics that the hazard switch in the center consul has a connection to the turn signals. And you mentioned how the lights were working fine one day until you turned on the hazard switch so maybe there is something going on with the hazard switch which is loading down the input to the instrument column. With the hazard switch Pressed, it puts a ground on the input to the instrument cluster for the turn signals so it should make the signal at pin FC9-6 on the instrument panel solid ground. If that hazard switch wasn’t solid ground when pressed and was floating somewhere in between some known values of other lighting circuits maybe you’re confusing this module circuitry and it’s turning on other various lights. I would disconnect the hazard switch and run some tests. There’s also an LED in that circuit which might be acting funny and putting a voltage on that and put the instrument cluster but that could only happen if you had a bad ground at FC 38.

But I will start looking at that hazard switch and all the connectors once again for any signs of corrosion or degree which would change the resistances of the signals.

 

Did you ever find the solution? I have about the same thing on my 2004 XJ8