Help no dash lights
- Thread starter jazak5
- Start date
-
What year, what car, what have you done lately?
67Dart273
Well-Known Member
Might be the cluster is not grounded
The dash circuit is a "trick"
The dash dimmer on the light switch gets it's power from the TAIL/ PARK circuit/ fuse. Power for the dash lamps goes through the dimmer, out on a tan wire and TO the fuse box to the end fuse marked "inst" for "instrument".
From that fuse, all dimmer controlled dashlighting is fed via orange wiring
THAT FUSE will ONLY HAVE POWER when:
The tail circuit has a good fuse and works
The light switch is in "park" or "head"
The dimmer control is turned "to the left"
If the fuse has power under those conditions, then SOMETHING that is dimmer controlled should work........the radio lamp, the heater bezel if lighted, the column shifter quadrent etc etc
The dash circuit is a "trick"
The dash dimmer on the light switch gets it's power from the TAIL/ PARK circuit/ fuse. Power for the dash lamps goes through the dimmer, out on a tan wire and TO the fuse box to the end fuse marked "inst" for "instrument".
From that fuse, all dimmer controlled dashlighting is fed via orange wiring
THAT FUSE will ONLY HAVE POWER when:
The tail circuit has a good fuse and works
The light switch is in "park" or "head"
The dimmer control is turned "to the left"
If the fuse has power under those conditions, then SOMETHING that is dimmer controlled should work........the radio lamp, the heater bezel if lighted, the column shifter quadrent etc etc
thrustbucket
Member
I currently have a similar problem.
I will state that I have removed my cluster. However, I am not sure if the gauge lighting was functional before that point.
I would/will check everything 67Dart273 has mentioned first and foremost, Continuity to ground, Voltage at the instrument fuse, blown fuse there, etc..
I had a problem with my headlight/dimmer switch. I was super deteriorated. I removed it and attempted to clean and repair it with De-Oxit spray. But the potentiometer/rheostat in the switch is a wire wound type and was completely clogged with corrosion. Preventing any current flow. I just pulled the wire coil out and cleaned the contacts with a points file, and I no longer have a dimmer.. But, I now have a dome light and column shift indicator.
Still no cluster lighting though.
jazak5: Does your dimmer work?
I will hopefully be getting into my lack of cluster lighting this weekend. I will share anything I find.
Just a note, if you haven't pulled the cluster before, be careful when disconnecting the large multi-pin connector on the rear of the cluster. Just keep wiggling lightly and pulling firmly and it will come off. Don't stick something like a flathead screwdriver in there to pry it out. Because it is easy to damage the traces on the acid etched PCB that it is attached to, and that would be bad.
I will state that I have removed my cluster. However, I am not sure if the gauge lighting was functional before that point.
I would/will check everything 67Dart273 has mentioned first and foremost, Continuity to ground, Voltage at the instrument fuse, blown fuse there, etc..
I had a problem with my headlight/dimmer switch. I was super deteriorated. I removed it and attempted to clean and repair it with De-Oxit spray. But the potentiometer/rheostat in the switch is a wire wound type and was completely clogged with corrosion. Preventing any current flow. I just pulled the wire coil out and cleaned the contacts with a points file, and I no longer have a dimmer.. But, I now have a dome light and column shift indicator.
Still no cluster lighting though.
jazak5: Does your dimmer work?
I will hopefully be getting into my lack of cluster lighting this weekend. I will share anything I find.
Just a note, if you haven't pulled the cluster before, be careful when disconnecting the large multi-pin connector on the rear of the cluster. Just keep wiggling lightly and pulling firmly and it will come off. Don't stick something like a flathead screwdriver in there to pry it out. Because it is easy to damage the traces on the acid etched PCB that it is attached to, and that would be bad.
thrustbucket
Member
I am working on my own cluster lighting problem as we speak. I only have a diagram for a '66 Signet. Without knowing your exact year/model.. I can only guess.
As far as controlling them, it looks like the signal indicator bulb/bulbs are controlled by the turn signal switch in the steering column. The switch connects a single bulb to the flasher in my case.
It seems the dash turn indicator, unlike all of the other cluster lighting, is Not tied into the cluster PCB ground plane. At least thats how my situation is. All the lighting in the cluster shares a common ground plane on the board. The entire board is grounded through the two hex screws that attach the PCB to the metal housing and it appears that grounds the lighting via the chassis connection. The exception here is the flasher bulb(s). I'm guessing it grounds through the turn signal switch.
If it is a cluster ground plane connection problem, you would probably have no cluster lighting and only dash turn indicators. But, if you have dirty PCB bulb contacts/shorted/damaged PCB traces you could have both problems at once. No lighting and no indicators. That's assuming your wiring is the same as mine.
You could have a bad/shorted turn signal switch?
But, since you said your external flashing lighting works, I would doubt its the switch.
It looks like the horn is tied in at that switch.. If the thing is REALLY shorted (both sections of the switch) you may be able to tell because you may have have no horn as well. But, the column switch would not impact the cluster lighting.. just the turn indicators.
I would pull the cluster and check all the traces for continuity, and clean the wiper contacts where the bulbs connect to the PCB. All A Bodies are really quite old now and damaged dirty contacts there will cause what you are dealing with. I'm also guessing no one has ever cleaned them. I would also clean the pins on the board connection and the female connectors in the master harness plug. The contacts should look like a penny that sat over-night in Coca-Cola. (Shiny). Not, like that one you found when you pulled the seats out. (Brown and Dull)
Do you still have/not have the same list of problems/functions you originally posted?
Paladin06
Well-Known Member
I went through this very issue just last week with the dash lights. Checked everything twice. Ended up being a fuse that look good was bad. Also be sure to clean the fuse mounting locations, mine were slightly corroded. Cleaned area, new fuse BINGO!!
Good luck.
Good luck.
found one problem on the left side///broken power feed pins on the circuit board
used solid copper buzz wire pre tinned everything// used a fiberglass pen to clean everything //soldered everything //checked , bulbs and board for continuity //cut pigtails off of the back,used a dremel tool to sand the backs of the pins flush with the board an a piece of gorilla tape on the back to keep the back from shorting out on the cluster frame.
stronger than factory !!!!!!
used solid copper buzz wire pre tinned everything// used a fiberglass pen to clean everything //soldered everything //checked , bulbs and board for continuity //cut pigtails off of the back,used a dremel tool to sand the backs of the pins flush with the board an a piece of gorilla tape on the back to keep the back from shorting out on the cluster frame.
stronger than factory !!!!!!
Last edited:
67Dart273
Well-Known Member
There's a good rebuild thread from long, long ago:
Printed circuit pins repair
cluster turn signal indicators branch off the front two wires as they come out of the TS switch on some years, and on some they branch off before they go through the bulkhead connector.
Three is little to go wrong there. If the signals work and the indicators don't it is most likely right at the cluster..........bad bulbs, sockets, poor socket connections, or the clusther connector
Printed circuit pins repair
cluster turn signal indicators branch off the front two wires as they come out of the TS switch on some years, and on some they branch off before they go through the bulkhead connector.
Three is little to go wrong there. If the signals work and the indicators don't it is most likely right at the cluster..........bad bulbs, sockets, poor socket connections, or the clusther connector
Paladin06
Well-Known Member
Great job.
thrustbucket
Member
Nice Work!
I got mine sorted yesterday as well. Dirty bulb sockets and PCB contacts. That was all.
-
