Had an interesting one today. 2017 ford explorer police interceptor came in for multiple warning lights on and a parasitic draw that would drain the battery completely over night. Checked for codes with IDS had multiple misfire codes for specific cylinders and random. Also had air bag light, but I could not communicate with it. After a little further investigation I could not talk to any modules on the HS1 can network. There were several of them.
Hooked my meter up to find a 6.53 AMP draw that wouldn’t let up. No wonder the battery was dead! Took a while to isolate it but narrowed it to cooling fan B+ from the battery junction box, and the problem was in that spot. Not outside of it. I removed the BJB to check the rats nest of wiring underneath it (this fuse box is integral to the body harness) and found the B+ fan wire melted with several other wires, including can bus wiring and relay grounds and other “switched hot” wires (this fan wire is hot at all times) which explained why I could energize and de-energize the PCM by removing the fan power fuse. I had to depin the fuse spade from the BJB (had to remove every relay and fuse within this fuse box to remove the locks for the terminals) and remove the terminal to repair the wire. I was able to save enough of the wire to reuse the spade, but the plastic lock was so brittle it broke when trying to release it. I had to epoxy the terminal in, which was a success (the other option is to replace the BJB and the body harness which was not happening).
After repairing all the wiring I ended up with 0.014 amps, or 14 milliamps. Very acceptable.
got my module communication back and had a 2 fold issue with the air bag. The clock spring failed (steering wheel buttons did not work) and the air bag failed (deployment loop resistance). Replaced both and that fixed those issues.
The misfires were repaired by a set of spark plugs. Nothing exciting there. There may be a small growing issue on cyl 1 with a little bit of a suspiciously clean plug, but no issues at this time. Will monitor.
Now waiting for a mid pipe for the exhaust and a RF wheel bearing for next week!
Not sure why it turned my photos…there correct before attaching them
Hooked my meter up to find a 6.53 AMP draw that wouldn’t let up. No wonder the battery was dead! Took a while to isolate it but narrowed it to cooling fan B+ from the battery junction box, and the problem was in that spot. Not outside of it. I removed the BJB to check the rats nest of wiring underneath it (this fuse box is integral to the body harness) and found the B+ fan wire melted with several other wires, including can bus wiring and relay grounds and other “switched hot” wires (this fan wire is hot at all times) which explained why I could energize and de-energize the PCM by removing the fan power fuse. I had to depin the fuse spade from the BJB (had to remove every relay and fuse within this fuse box to remove the locks for the terminals) and remove the terminal to repair the wire. I was able to save enough of the wire to reuse the spade, but the plastic lock was so brittle it broke when trying to release it. I had to epoxy the terminal in, which was a success (the other option is to replace the BJB and the body harness which was not happening).
After repairing all the wiring I ended up with 0.014 amps, or 14 milliamps. Very acceptable.
got my module communication back and had a 2 fold issue with the air bag. The clock spring failed (steering wheel buttons did not work) and the air bag failed (deployment loop resistance). Replaced both and that fixed those issues.
The misfires were repaired by a set of spark plugs. Nothing exciting there. There may be a small growing issue on cyl 1 with a little bit of a suspiciously clean plug, but no issues at this time. Will monitor.
Now waiting for a mid pipe for the exhaust and a RF wheel bearing for next week!
Not sure why it turned my photos…there correct before attaching them
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