69 Roadrunner dash wiring issues

Guys i am at the point where i'm installing my dash in my 66 RR. I installed all new harness's in the car including a new dash harness. The issue i have is when i connected the battery and started checking to see if everything is working it fried part of my gauge cluster PCB board when i turned on the lights. It burned the trace right off in one spot near the gauge voltage regulator. It also appears i have 12v power to both the main red and black wires that connect to the instrument cluster from the dash harness. Anyone have an idea of what could be causing this? I'm guessing it sent 24v thru the PCB so thats why it burned up in that spot.

I'm guessing at this from your description but the "main" red & black wires are for the ammeter and will have 12V if you tested them at the gauge connected. The red wire has a splice that also feeds the light switch, the ignition switch and the unswitched side of the fuse panel. If you have pictures of the PCB it would be easier to see which run burnt. However, when you turned on the light switch, it applied battery directly to something that was grounded. Did any fuse fail?

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerA.JPG
http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerB.JPG

what are you using as a reference guide? do you have a wiring diagram? i replaced all my wiring in my 69 RR, and it's something that has to be done methodically, and double checked before hooking up to the battery. by the sounds of it, you def have a short somewhere.

Shorthorse said:

I'm guessing at this from your description but the "main" red & black wires are for the ammeter and will have 12V if you tested them at the gauge connected. The red wire has a splice that also feeds the light switch, the ignition switch and the unswitched side of the fuse panel. If you have pictures of the PCB it would be easier to see which run burnt. However, when you turned on the light switch, it applied battery directly to something that was grounded. Did any fuse fail?

Click to expand...

Just to correct a minor point, it's the BLACK ammeter wire that branches off to feed accessories and the headlights.

If you do NOT have a shop manual or wiring diagram, go to MyMopar where you can download them free

Stuff

http://www.mymopar.com/index.php?pid=31

69 shop manual

http://www.mymopar.com/downloads/servicemanuals/1969_Plymouth_Service_Manual.zip

From this page

http://www.mymopar.com/index.php?pid=27

A "full set" of diagrams which is actually the same as what is in the shop manual, above:

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerFull.pdf

Below are "aftermarket" simplified diagrams from MyMopar. These are sometimes easier to follow but are NOT always complete and sometimes leave out important connectors. They are however useful

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerA.JPG

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerB.JPG

What might be the cause? Don't know. Do you have the cluster grounded? If not you may have one of the ammeter wires (the large black and the large red) shorting to the PC board.

The "plug in" instrument (gauge) regulator could be shorted

One thing you can do "until you have" things sorted out is to remove the black and red ammeter wires, and bolt them together and tape them off. This will isolate them from the cluster. They must be connected in place of the ammeter to get the system to work.

Check with your multimeter from both ammeter studs on the cluster to a ground point on the cluster. There should be NO continuity.

http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerA.JPG
http://www.mymopar.com/downloads/1969/69BelvedereGTXSatelliteRoadRunnerB.JPG

When I installed mine I did not have the cluster grounded and when I touched the neg terminal of the battery it sparked,i bolted the cluster in the dash and it fixed that.