05/19/2026
Because, reasons. And no good ones. Wiring "repairs" like this can cause a lot more damage than most people realize. Luckily (at least to this point, and as far as I can tell) there hasn't been any major damage caused by this rats nest of wiring repairs. They have the 5V reference tied back into another circuit, from a green wire to a green/white wire. After this is fixed, I'll verify it's working properly before proceeding with the timing belt and spark plugs on this 3.0L Toyota. They had it taped up really well, it actually didn't look like it had been repaired or messed with until I pulled everything back. Wiggle testing and manipulating the harness while watching my voltages on the oscilloscope helped to pinpoint this mess.
Complaint was a check engine light, which was due to a fault in the Transmission Fluid Temp Sensor circuit.