Posted By: shanker
Ignition Wiring Problem I can't seem to figure out - 09/11/20 03:39 AM
This is in my wife's 74 Ramcharger (440/Auto).
I've just finished up swapping in 1 ton axles out of first gen cummins truck and over the last few years I've been working on this truck little by little and it's time to fire it up and drive it out of the garage for the first time in 10 years!
Anyhow, after hooking everything up, when I turn the key forward, to the run position, the coil stars humming. Turning the key to the start position I get no fire and no voltage.
The Ignition 2 Lead is the one that has me really frustrated, it should ONLY have power in the start position and provide power to the coil, instead it's got 8.9V in Run, and no voltage in start.
I've only got one electrical tester, but I think something is backfeeding maybe? I've used two NEW ignition switches and have the exact same results. There are NO modifications to the wiring and no aftermarket anything. I want to make sure everything works 100% before I change anything (planning on ampmeter bypass but that's about it)
I've recently went thru the entire Dash, Forward Light, Rear, and Engine harnesses verifying every single wire for continuity and verified they're in the correct bulkhead position against the 1974 Factory Service Manual. The Dash Harness is out of a 75 Dodge Truck with Factory A/C (all of it's wiring was identical to the FSM), and the Forward Light & Rear Harnesses are out of a 74 W200, and the Engine harness is a NOS M880 harness. Everything in all of the harnesses matched up to the FSM.
I'm hoping someone here has come across a similar issue or perhaps can lead me in the right troubleshooting path.
I've just finished up swapping in 1 ton axles out of first gen cummins truck and over the last few years I've been working on this truck little by little and it's time to fire it up and drive it out of the garage for the first time in 10 years!
Anyhow, after hooking everything up, when I turn the key forward, to the run position, the coil stars humming. Turning the key to the start position I get no fire and no voltage.
The Ignition 2 Lead is the one that has me really frustrated, it should ONLY have power in the start position and provide power to the coil, instead it's got 8.9V in Run, and no voltage in start.
I've only got one electrical tester, but I think something is backfeeding maybe? I've used two NEW ignition switches and have the exact same results. There are NO modifications to the wiring and no aftermarket anything. I want to make sure everything works 100% before I change anything (planning on ampmeter bypass but that's about it)
I've recently went thru the entire Dash, Forward Light, Rear, and Engine harnesses verifying every single wire for continuity and verified they're in the correct bulkhead position against the 1974 Factory Service Manual. The Dash Harness is out of a 75 Dodge Truck with Factory A/C (all of it's wiring was identical to the FSM), and the Forward Light & Rear Harnesses are out of a 74 W200, and the Engine harness is a NOS M880 harness. Everything in all of the harnesses matched up to the FSM.
I'm hoping someone here has come across a similar issue or perhaps can lead me in the right troubleshooting path.