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Instrument Lights not working. (No Power at dimmer)

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Old 07-17-2012, 10:35 PM
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vdubr
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Default Instrument Lights not working. (No Power at dimmer)

I have no voltage on either side of the dimmer. I've checked fuses but I am having a hard time finding an accurate fuse diagram. The electrical diagrams I have are confusing at best. The dash and harness have been replaced in this car and that is when this problem started. I need some pin out info so I can start testing or come up with a workaround if I find a short.

Thanks,

86.5 928
5 Speed LSD
Old 07-17-2012, 10:37 PM
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SeanR
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Do you have the workshop manuals on paper or CD? Both of those have the wiring diagrams.
Old 07-17-2012, 10:42 PM
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vdubr
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CD but my wire colors don't seem to match up. My dimmer has Brown and Blue. The manual shows black and black blue. Did I hook something up wrong or do I have a short in my harness? The diagrams don't seem to call out block numbers or anything so I can test at the panel. IE, where does the power to the dimmer come from? The light switch via the fuse panel then back up?

Edit, I take it back. I do see the page that calls out the blocks now. It looks like fuse 44. How do I make sense out of all this? lol
Old 07-17-2012, 11:15 PM
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Dean_Fuller
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I would try cleaning the connector with some electronic spray cleaner. It might have a thin layer of .....stuff. While i was reassembling Marvin there were several connections like that I had NO power..then clean and SCRAP the connector and power was back.

What color wires go to your OD reset??? May be swapped.

Also once you get power I suggest just jump the two together and by pass the dimer. Its too dim anyways.
Old 07-17-2012, 11:28 PM
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vdubr
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Getting too dark to see under the pod now but when I hit the OD reset button the OD resets so that can be eliminated. I don't see any other wires. May just pull the pod in the morning but I welcome any suggestions.

Agreed on jumping the wires.
Old 07-17-2012, 11:54 PM
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SeanR
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You can eliminate the dimmer by connecting the wires straight (I swear I just gave this advice this morning but can't find out where )

If you have no lights with the dimmer out of the loop, then you need to look at the fuse panel and then the connections at the back of the instrument cluster.

have you had the pod off for anything lately?
Old 07-18-2012, 12:03 AM
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vdubr
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There is no voltage at either of the dimmer wires. Connecting them has no effect. I have gone through all the fuses and see nothing out of the ordinary.

The pod, dash, and harness came from another car. I recently reinstalled the pod. I beleive the problem lies at the fuse block but don't know what to look for. I am not even sure which fuse it is. The FSM says #44 but that is a switched fuse so I am not sure it is the cluster lights.

If someone could verify the wire colors at their dimmer then at least I'll know if I'm looking at the right pair.
Old 07-18-2012, 12:07 AM
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SeanR
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Originally Posted by vdubr
There is no voltage at either of the dimmer wires. Connecting them has no effect. I have gone through all the fuses and see nothing out of the ordinary.

The pod, dash, and harness came from another car. I recently reinstalled the pod. I beleive the problem lies at the fuse block but don't know what to look for. I am not even sure which fuse it is. The FSM says #44 but that is a switched fuse so I am not sure it is the cluster lights.

If someone could verify the wire colors at their dimmer then at least I'll know if I'm looking at the right pair.
The wires will go through your light switch (top left on the pod)

When you turn your key on, do you get all the warning lights?
Old 07-18-2012, 12:44 AM
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WallyP

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Power for the dash lights comes from Fuse #44, out thru a black wire in F24 (Plug F, right column, 4th wire up) to the potentiometer, and out thru a black/blue wire to the lights.

Brown is ground on the 928.

The speed warning buzzer has a brown and a blue wire - no idea whether you have that or not.

Either you have the wrong wires hooked to the light dimmer, or someone has changed the wires...
Old 07-18-2012, 01:28 AM
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Dean_Fuller
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I JUST finished Marvin's Pod install and I did notice an EXTRA pod plug that is used only if the car is a euro ( I think for fog lights? ) anyway...I think I remember a loose ground and another brown with I think a white stripe that I saw nothing to plug to so I wrote it off as a "none used" wire in the harness.

My point is...there are wires in the harness that go to nothing because the model car does not need them...i.e. euro.

DIG to find the black/blue wire...I bet its buried in the back of the pod I bet.
Old 07-18-2012, 02:00 AM
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vdubr
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Thanks, I am on the same page. I must have the wrong wires connected. That should be an easy fix. I'll pull the pod if I can't find the bl,sw and sw. I looked at several years and the wire color is consistent. The harness is unmodified.

Wally, #44 is switched, do the instrument lights only work with the key on?

Sean, all my gauges and idiot lights are functioning. Just no power at the dimmer.
Old 07-18-2012, 10:28 PM
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vdubr
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Got this figured out. Pulled the pod and found the black/blue and black. Bridged them and all is well. Now on to my vacuum problem that is affecting my climate control.
Old 07-18-2012, 10:35 PM
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Great to hear it.
Old 11-19-2018, 06:58 PM
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Anders Flodin
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Old thread but just did the same thing, managed to glue a plastic cover over the dash and while doing so, got the blue/black and black wires glued in behind the dash cover....

And then there are 2 wires, brown and blue that fits perfectly to the rheostat but they are not the right wires....dunno where they should go, have to check the wire diagram



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