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 #392632  by tveh
 
So I'm decently sure this is the phase morpher issue documented elsewhere, but I've heard other people talk about a "power supply" going bad. Likewise, the walkthrough on this topic don't seem to have working photos anymore.

- Backlighting on the cluster works inconsistently, usually not at all.
- Slapping the dash usually causes it to flash on and back off, though this never fixes it.
- The cruise control light doesn't light up, though cruise control does work (well, it works when it has good vacuum hoses.)

When the backlight does work, which seems somewhat temperature-dependent, it works perfect. Turning the lights on and off, even turning the car on and off in a short period of time, doesn't stop it from working, though sitting for a longer period will often lead to it stopping again.

Anyone have any insight on this issue?
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 #392634  by FIREM
 
Does the clock light work properly? If not the issue may be with the head light switch.
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 #392695  by tveh
 
FIREM wrote:Does the clock light work properly? If not the issue may be with the head light switch.
You know, I'm pretty sure it does but I'll check on that.

I always leave the switch on auto, so I figure if it is a problem with that then there's a switch of some kind that comes before the actual knob and dial? When it works I can flick those on and off all I want without it cutting out.
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 #392700  by LUNAT1C
 
Sounds to me like a cold solder problem on the power supply.
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 #392703  by tveh
 
LUNAT1C wrote: January 22nd, 2023, 8:47 pm Sounds to me like a cold solder problem on the power supply.
Seems possible. Is the power supply for the backlighting external to the cluster or integrated?
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 #392704  by LUNAT1C
 
tveh wrote: January 22nd, 2023, 10:47 pm
Seems possible. Is the power supply for the backlighting external to the cluster or integrated?
I haven't needed to deal with it myself, but my understanding is it's part of the cluster, not a separate module.
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 #392709  by tveh
 
LUNAT1C wrote: January 23rd, 2023, 1:13 am I haven't needed to deal with it myself, but my understanding is it's part of the cluster, not a separate module.
Seems like the clock light is working at all times, yeah.
I guess I'll pull the cluster and check for cracked solder.
User avatar
 #392710  by LUNAT1C
 
tveh wrote: January 23rd, 2023, 6:13 pm Seems like the clock light is working at all times, yeah.
I guess I'll pull the cluster and check for cracked solder.
Might be difficult to check if the problem is intermittent. Multimeter might still show it's OK. There is a similar issue with the ATC display where cold solder cracks at the main three blue resisters, that are nearly invisible without a microscope (the cracks), are the issue and are fixed with some careful light re-soldering. If you're good with fine electronics soldering, then it might be worthwhile to put a little bit of fresh solder on the power supply joints if the multimeter doesn't show anything obvious.

If that still doesn't fix it, then the issue might be internal to the power supply. Replacement might fix it, but I would swap out the cluster at that point. The spare dash I have (for that common dash crack issue) I bought with a cluster from another Special just in case I ever run into that issue, assuming the spare I have is any good. :lol:
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 #392711  by tveh
 
LUNAT1C wrote: January 23rd, 2023, 7:08 pm
tveh wrote: January 23rd, 2023, 6:13 pm Seems like the clock light is working at all times, yeah.
I guess I'll pull the cluster and check for cracked solder.
Might be difficult to check if the problem is intermittent. Multimeter might still show it's OK. There is a similar issue with the ATC display where cold solder cracks at the main three blue resisters, that are nearly invisible without a microscope (the cracks), are the issue and are fixed with some careful light re-soldering. If you're good with fine electronics soldering, then it might be worthwhile to put a little bit of fresh solder on the power supply joints if the multimeter doesn't show anything obvious.

If that still doesn't fix it, then the issue might be internal to the power supply. Replacement might fix it, but I would swap out the cluster at that point. The spare dash I have (for that common dash crack issue) I bought with a cluster from another Special just in case I ever run into that issue, assuming the spare I have is any good. :lol:
Yeah the dash on my 2002 Concorde Limited finally cracked. It was my fault--we moved and I didn't sunshade it for the last three years. About to order a kit from https://www.classicdyeproducts.com/chry ... ior-colors here and attempt a quality repair.

Does your spare cluster have automanual? I might be interested in buying it off of you if it does.