I hate electrical work!! I noticed that nothing in my instrument panel worked except the speedometer so I took out my seats to make room and pulled the panel out and take a look. It looks nearly new except the lenses were clouded beyond use. Brasso fixed that. All the copper looked fine, bulbs looked new circuit board clean. So I cleaned the plug and reinstalled and checked my fuse panel. AHA! Kinda. fuses are fine but I'm not getting 12v to #3, the one for panel lights. But #4, the one for indicator lights is getting 12v on both sides of the fuse but apparently not making the trip to the dash. #5 (heater fan control) is getting the same, but may just be bad motor. The dash is what I'm concerned about. I took apart connectors under dash and cleaned them, but it made no difference. Took the fuse panel out and cleaned where it plugs together. samo. I ran a hot wire to the #3 fuse but still no lights, indicators or fuel gauge. I kinda ignorant about wiring. Not sure where to start. Grounds maybe? Run a new heavy hotwire to dash and make new panel? Like I said. I hate wiring...Where do I start? Beer time....
Maybe check your headlight switch. On my 73, the dash light go on and off as you juggle the switch. I will replace the switch when I have a chance to see if it makes a difference. Good luck, sometimes they take a while to find.
After I make sure I have 12v to something I always check all the grounds. It seems like the majority of electrical issues I have had is because of a bad ground
I love electrical work!! Since you have multiple problems with different circuits involved I agree w/ turbo, ground issue. Let me know what year you have and I will try to help out more if needed.
I have a '74 wagon. I was kinda wondering about ground. Finding them might be a little hard. Seems sometimes they hide them away where you can't get to them. There are 2 under the hood that I saw, but it's kinda hard for me to explore up under the dash. (old & fat). I know the dimmer switch is in sad shape, and I see that there is one on ebay. Headlight switch may be more difficult to come up with new.
The black wire at the cluster connector is the ground. Test it there. Hook your test light clip on a 12v source and touch the probe to the black wire, it should light up. If not and you don't want to trace it out, just run a new wire. Tap into the black wire and ground it somewhere.
Next problem: no power to panel lamps fuse. It gets power from the H/L switch on the light blue/red tracer wire. With the park lamps on, check for 12v at the H/L switch. With the cluster out you should be able to get to it. No power=bad switch. Power=broken wire from switch to fuse box. (or a bad connection) Again, if you don't want to trace it out, run a new wire from the switch to the fuse box.
Also scroll down in this section, wedge446 posted a pinout chart. very helpful.
Quote from: 71pintoracer on September 09, 2008, 08:13:02 PM
The black wire at the cluster connector is the ground. Test it there. Hook your test light clip on a 12v source and touch the probe to the black wire, it should light up. If not and you don't want to trace it out, just run a new wire. Tap into the black wire and ground it somewhere.
Next problem: no power to panel lamps fuse. It gets power from the H/L switch on the light blue/red tracer wire. With the park lamps on, check for 12v at the H/L switch. With the cluster out you should be able to get to it. No power=bad switch. Power=broken wire from switch to fuse box. (or a bad connection) Again, if you don't want to trace it out, run a new wire from the switch to the fuse box.
Great post !!! ;D ( check your feedback score )
THANKS 71pintoracer. I'll do just that. What a great site this is. What a great bunch of folks!!
OK, here's where I'm at. I pulled the dash again and tested the ground wire(s) at the plug. The test light lit up, so I must have a good ground. Then I pulled the headlight switch so I could get to it easier and put a meter probe at the light blue wire w/red stripe. Pulled on the park lights and it showed voltage. I could turn the dimmer back and forth and vary the voltage so ran it up all the way and checked the same wire on the panel plug and it showed full voltage there. So, I'm getting voltage to the dash panel (or at least the male plug) but nothing at all works on it. Fuel gauge dead, indicators don't light up when key is turned on, no dash lights, nothing. Must be a problem with the panel itself. There is what appears to be a regulator attached to the circuit board. Could that be it? surely the whole circuit board can't be bad. I'm kinda stumped here. Seems the plug is making good contact as indicated by marks on the female side. This makes no sense to me, but then I'm an electronics idiot, too. Any Ideas?
There seems to be a break in the printed circuit provided you are getting a good connection at the plug, but after plugging it in and out like you have it should be OK. Still you may want to clean the terminals on both the connector and the cluster side with a scotch brite pad or very fine sandpaper. The regulator is just that, it cuts the voltage to the gauges, has nothing to do with the dash lights.
I may be way out in left field with this, but count the number of contacts on the harness plug at the cluster and the number of contacts on the cluster PCB itself. IIRC, there should be either 12 or 14. Ford changed the count in 74 becuase they changed the cluster 'idiot' lights. If the # of contacts are mismatched, tada, you found your problem. If they are the same, then heck I dunno...unless you want to ring out all the pcb lines with an ohmmeter...
I have ohmed out the pcb's before and repaired the break. Ford makes this stuff called "heated backlight grid repair" that is used to fix breaks in the grid lines on rear defrosters. It will also work on pcb's.
Quote from: douglasskemp on September 11, 2008, 02:16:47 PM
I may be way out in left field with this, but count the number of contacts on the harness plug at the cluster and the number of contacts on the cluster PCB itself. IIRC, there should be either 12 or 14. Ford changed the count in 74 becuase they changed the cluster 'idiot' lights. If the # of contacts are mismatched, tada, you found your problem. If they are the same, then heck I dunno...unless you want to ring out all the pcb lines with an ohmmeter...
Good call douglass
Update here. I finally determined that all the bulbs are good, but every stinking one of the sockets were bad. Bought 10 new sockets and now everything lights up. As for the fuel gauge, I pulled it and took it apart and found out that one of the tiny wires that connects to the post was broken. I also determined that it was very likely me that broke it when I tried to take one of the nuts off. Seems the stud turned in the plastic too many times before I realized what it was doing and wrapped up the wire to the breaking point. I worked for several hours trying to re-solder that tiny little thing and finally gave up. I guess my next step will be to buy a pedestal mounted gauge and matching sending unit as I don't think I could find a working original unit. I'd be afraid that whoever removed it would do the same thing as me and break the wire. I think as long as the dash is loose anyway, I might as well replace the light switch while they are still available from NAPA.
Quote from: oldandcrotchety on September 17, 2008, 08:12:23 AM
...as I don't think I could find a working original unit...
Heck, it's worth a try to find one here. I'll bet there is someone willing to part with one on the cheap. I am sure I have a few extras somewhere back home, but all my stuff is in DEEP storage.
Thanks for the up dates.