Replacing The Printed Circuit On The Back Of A 1969-1970 Mustang Instrument Cluster – San Diego, CA

If you ever had to pull the instrument gauge panel out of a 60′s Ford,  you had to remember where all the wires plugged back into. Starting in 1969, Ford started using integrated circuitry on the back of the instrument gauges.  Thin copper strips were laminated between two sheet of thin clear plastic, so it could easily contour on the back of the instrument housing.  After 40 years, they delaminate, and get damaged by moisture. Also, they can easily short out by pinched wires from taking them in and out of the Mustang’s dash over the years.  Luckily, the printed instrument circuits are reproduced for the 69-70 Mustangs.  This particular 69 Mustang had all of the above issues.  There were signs of delaminating, but that was not the ultimate fate of the instrument panel.  There were some wires that got pinched between the dash brace and the printed circuit. You can see by the pictures that this happened in a few spots.  Before re-installing the instrument cluster with the new printed circuit, I checked all the dash wiring for shorts.  Also, I had to replace a bad heater motor, so the lower metal dash panel had to be patricianly removed too.  Removing the dash can be time consuming, so you only want to do it once.  I did find one wire that had burned nearly through the entire harness, and had to be replace it. Luckily, it did not damage any of the neighboring wires. Once the instrument cluster was bench tested, I re-installed everything, and the instruments gauges worked as good as new.

Part One – Adding new life to Classic Mustang Gauges – 1967 Ford Mustang

No, your 1967 Mustang gauges are not factory yellow. They’re just worn out. You can add some bling back to your Mustang’s dash just by replacing the instrument bezel and lens. 1968 and 1967 Mustang gauges have their own wiring harnesses, so removing them are fairly easy. First you will need to remove your heater control panel by removing the top 2 screws and bottom 2 screws. Next, just let the panel hang down, but do not detach the cables. Then, remove all the instrument bezel screws, and lightly pull the bezel out until you feel some resistance. Next, reach up into the heater control opening, and reach behind bezel to unscrew speedometer cable. It should be hand tight. Afterwards,  pull bezel out a little more, so you can disconnect the 3 plugs. One of them will plug directly into the back of the bezel to the wiper switch. Also, it’s a good idea to drape a cloth on the steering column to protect both the bezel and column from scratches. At this point, you should have a instrument cluster sitting in your lap.

As you can see in the picture, begin by removing all the screws in the back. Now you can separate the bezel from the gauges. If you’re working on a 1968 bezel, you will have to remove the wiper switch knob with a small allen wrench before removing the bezel. Also, for both 1967 and 1968 equipped with a clock, you will have to remove the set knob with a tiny  flat blade screw driver. Ok, now you can remove the bezel. Next, you will have to remove the individual lens’s from the back of the bezel. To make it easy, keep the in the order you removed them. They only go back on one way. Once apart, try to clean out the dust as much as possible. Low pressure air nozzle works best, but make sure not to blow directly on the needles. Cleaning the dust is important because it will stick on the inside of the new bezel lens, and will be hard to clean them. You can make the needles new looking again by painting them with fluorescent orange model paint before assembly. For instrument clusters without the clock, don’t forget to transfer the black delete hole plug. Now, you just re-assemble in the reverse order, but make sure you put the light separators in the same way as they came out. There’re cardboard, and will damage easily. One last thing before installation, replace all the (1895) light bulbs whether they work or not. They’re cheap, but it’s a pain if you have to remove the bezel for just one burnt bulb. Now re-install the cluster, and enjoy!

For instrument gauge troubleshooting check out Mustang Monthly’s article