We are nearing the completion of this project. It will have been 3 years by the time we finish phase 1. This is the engine and drive train installation and associated wiring and exhaust. Phase 2 will be wheels, brakes and navigation with rear view camera and some interior appointments.
Our subject is a red 2007 EXP with chrome wheels. As such it has a PWM fan. Variable speed, commanded by the ECM in response to temperature and perhaps something else. Super simple circuit. 3 wires: +, - and control. The story to follow is nothing I enjoyed.
The OEM fan was mounted upside down for fitment reasons. The connection plug was now in the opposite side of the car and I needed to relocate the plug to make the fan work. I cut the wires, extended them, reconnect the fan and following; began to test for power and function. Could not find power at the + wire. Went to the manual and looked up the wiring circuit to the fan. Circuit consisted in a single 60 amp fuse. Labeled #1 in the fuse box and the largest capacity fuse in the whole car. Can't get easier than that.
I followed the voltage through the fuse and the box architecture. Found the wire at the connector to the fuse box; but to my surprise it did not go to the fan. WHaaat? FSM says so! After performing serious surgery to the harness, I discovered an additional and identical, red with black line wire. It was easy to follow it right to the ABS module. The 60 amp circuit is feeding the ABS unit, which BTW, is supposed to be fed power from 3 circuits, largest being 40 amp.
Guess saying "go figure" is in order.
The fan was connected to power w/o a fuse, from the factory to us. Seems like an improperly made it to the production line with a fix. But with some curiosity, the manual and a lot of time, the details were elucidated. The car had just under 10,000 miles and these was no evidence of attempts at customization or repairs. I will be posting pictures soon.