Lights don't work on instrument cluster

Discussion in 'Classic Mustang Specific Tech' started by fastdave, Jan 30, 2006.

  1. I put in a new instrument cluster in my 67 fastback but I cant get the instrument lights to come on. It seems like it could be a ground. Does the cluster have screwed in place for the grounding? What else could it be? Everything else works correctly.
  2. Check the fuse

    See if there is voltage at the fuse

    Check for power on the blue/red wire - It starts at the light switch, goes to the fuse block, then to the instrument cluster.

    If you suspect the ground, a check with a meter on any of the instrument lamps ground side will show 12V.

    I think the ground is a black wire screwed to the metal brace right behind the gage panel.
  3. Not sure if this is true or not, but one time my dash lights went out and I pulled the sucker appart and found a dead bulb. After I replaced the one dead bulb then they all worked again. I'm not sure if they are supposed to be wired like xmas tree lights or not but my car has gremlins in it so I'm never supprized when I findy wacky wiring. Try replacing the bulbs and see what you get.

    If you need the wiring diagram I can scan my Ford manual for you. Just let me know.
  4. QUICK response! Thanks guys. I will check it this weekend.
  5. On the '65-'66 the cluster has to be screwed in to ground it. There are metal tabs behind the plastic that complete the curcuit through the screws and metal dash. I'm not sure, but I think the '67s may ground the same way.
  6. They are wired in parallel, so one lamp blowing will not prevent the others from working.
  7. My 67 dash doesn't have the dedicated ground wire, the mounting screws provide ample ground. Having said that, someone may have circumvented that original wire in the last 40 years or so.
  8. My 67 DOES have a ground wire and it is definately stock.
  9. Mine also has the dedicated ground wire, But its weird because some of the lights work and some of them do not, such as the light that tells you that the brights are on works, but the backlighting to the spedo and the gas guage does not, I replaced all the wireing harnesses in the car andd this is what came up, after muffing around with it for about 5 days i finaly decided that i didnt need them that bad. :nonono: