This 1992 Ford F150 came in with a no charge complaint. The battery, alternator and alternator connectors had already been changed. I had to start with improving the splice connections that were used when the repair harnesses were installed. There had been a combination of scotch lock type connectors and poorly crimped cheap splicing connectors used. Once all of that was straightened out I checked for the proper circuits at the harness connectors.
The two large black/orange wires have power at all times.
The white/black wire in one connector is supposed to have continuity to the same colored wire in the other connector.
The yellow wire in the smaller connector has battery power at all times.
The green/red wire has power on it with the ignition switch turned on. Power feeds from the ignition switch to the instrument cluster charge indicator bulb and out to this connector. Depending on the particular year, the voltage can range from 5 to 12 volts with the connector unplugged from the alternator.
All circuits tested okay on this truck with the exception of the green/red wire.
There is an in line harness connector for the green/red wire. On this truck it was located at the edge of the battery tray as shown below.
The wire was broken off on one side of the in line harness connector.
The wire had been improperly looped under another harness and had the wire under a slight tension. This coupled with 20 years of vibration broke the wire off cleanly.
I had to lift the locking retainers on both sides of the harness connector in order to separate the two halves.
In most cases this connector would simply be cut out and the two wires would just be spliced back together. I had the correct terminals so I elected to install a new terminal and wire in the old connector body. I had to lift the gray locking tab out of the old connector.
I stuck the new terminal and wire in and spliced it back to the original wire. Reassembled all connector and re-secured the harnesses back into position using the original push pin retainers.
Now I have the proper power on the green/ red wire and the no charge problem is corrected.