As I understand, the gauge cluster grounds to the housing itself. I know I'm getting power to the gauges for sure...when I hooked the battery up and keyed the power on, I saw the oil pressure gauge tick up slightly and stay there, and with the fuel tank and sender out the LED is still flashing away for low fuel. Is this looking like a case of adding in a ground at this point?
I spent ten years wiring helicopters, and Chrysler gauge clusters just kick my
.
It's usually easier when ya have the schematic or 1/2 of it memorized.
The ground for the dash is in the 6 pin connector more or less behind the speedo. Solid black wire in the middle. Other end is a ring lug to the dash frame more or less behind the ash tray (CI 34). Ground side of gauges, dash lamps and voltage limiter are tied together in the circuit board. So if the lights light, ya got a ground. An easy sanity check is one lead of the ohm meter to a handy body ground like the A pillar trim screw or visor mounting screw and bounce around the front of the cluster with the other lead.
Not surprised the bulkhead connector was clean - sealed up pretty well from the factory and well hidden from rain water. The connectors at the sender for temp, oil, fuel are more likely culprits. Push on plug for temp sender is often rusty, spade connector for oil is often loose / corroded / hanging on by a thread, ground strap at tank is always rusty and will often just crumble in your hand. At this point, it's divide and conquer - check continuity from bulk head connector to senders and from bulkhead to circuit board.
Just remembered this one: one of mine had a problem where every now and then the dash lights didn't light. Usually in cold weather and eventually came on. When it turned in to a hard fail, reseating that 6 pin connector (CI 5) fixed it - the orange wire across from the ground is the dash lamp hot. If the stray jumpers from way back was an attempt to fix a flaky ground, I bet it's right there.
