Post by RIP OLDS on Oct 30, 2018 22:38:17 GMT -5
This is a follow up to my previous posts on this issue. Maybe it will help someone at some point. In short the Gen light was illuminating dim when in drive and park, and bright red when in reverse, and the reverse light circuit was not working. The voltage at the reverse light circuit fuse was 4 V, and dropped to zero when the reverse light switch was engaged. I figured the gen light and reverse light issue was one in the same, so I proceeded with troubleshooting the light circuit.
Using the wire diagram, I traced every connection point in this circuit, including grounds. This circuit ran under the dash, the PCB, in the trunk, under the hood...etc. First thing I did was check continuity of all these wires, and looked for rust, but all checked out fine. I initially thought it would be the grounds in one of the reverse lights since I recently painted the bumper brackets. But energizing the rear light directly from the battery ruled that out as they worked fine. I then proceeded to energize each connection point in this circuit with 12 V from the battery. Each time the circuit worked fine. But when energized from the fuse box, the voltage in the circuit would drop to zero. Strange issue. If I energized the fuse box fuse for this circuit directly from the battery it worked fine. Extremely frustrated at this point.
The last connection point to check was the ignition switch. I removed the switch and dropped it under the dash to be accessible. I was hopeful this had to be the area problem as I had checked everything else. I removed the ignition switch connector and energized the circuit from the battery. Circuit worked fine. So the last thing it could possibly be was the ignition switch itself. I used jumpers from the ignition switch to the connector to measure voltages. To my surprise all was working with the jumpers. It should not have worked based on all my other tests. The only difference was jumpers being used instead of the plastic connector directly connected to the switch.
I plugged the connector back in and all was working. I was thrilled it was all working, but of course confused as I did nothing other than unplug the connector and then plug it back in. My feeling is that the connector was not 100% pushed all the way in, and the reverse light circuit connection was less than solid and could not hold current.
All this of course took a Saturday for three weekends in a row, including taking all the A/C stuff out from under the dash, removing the fuse box, the wiper motor (to get to the fuse box plugs) and removing the console.
One tricky issue to solve, thankfully cost nothing but time. Thanks to two friends who helped out as well, a fellow 65 442 owner and a 72 vetter.
Using the wire diagram, I traced every connection point in this circuit, including grounds. This circuit ran under the dash, the PCB, in the trunk, under the hood...etc. First thing I did was check continuity of all these wires, and looked for rust, but all checked out fine. I initially thought it would be the grounds in one of the reverse lights since I recently painted the bumper brackets. But energizing the rear light directly from the battery ruled that out as they worked fine. I then proceeded to energize each connection point in this circuit with 12 V from the battery. Each time the circuit worked fine. But when energized from the fuse box, the voltage in the circuit would drop to zero. Strange issue. If I energized the fuse box fuse for this circuit directly from the battery it worked fine. Extremely frustrated at this point.
The last connection point to check was the ignition switch. I removed the switch and dropped it under the dash to be accessible. I was hopeful this had to be the area problem as I had checked everything else. I removed the ignition switch connector and energized the circuit from the battery. Circuit worked fine. So the last thing it could possibly be was the ignition switch itself. I used jumpers from the ignition switch to the connector to measure voltages. To my surprise all was working with the jumpers. It should not have worked based on all my other tests. The only difference was jumpers being used instead of the plastic connector directly connected to the switch.
I plugged the connector back in and all was working. I was thrilled it was all working, but of course confused as I did nothing other than unplug the connector and then plug it back in. My feeling is that the connector was not 100% pushed all the way in, and the reverse light circuit connection was less than solid and could not hold current.
All this of course took a Saturday for three weekends in a row, including taking all the A/C stuff out from under the dash, removing the fuse box, the wiper motor (to get to the fuse box plugs) and removing the console.
One tricky issue to solve, thankfully cost nothing but time. Thanks to two friends who helped out as well, a fellow 65 442 owner and a 72 vetter.