Hi There, I'm Clayso a certified master automobile technician with 30 years of automotive repair and diagnostic experience and I'm here to help with this problem. Additional services may be offered for detailed information.
At the 2-pin connector on the Electro-Hydraulic Power Steering pump unit (EHPS), check that the Red wire has constant battery voltage from fuse FL4 100 amp in the left side of the engine
compartment fuse holder and that the Brown wire has a good ground behind the battery.
2. At the 3-pin connector on the EHPS, the Green/White wire should have ignition-on battery voltage from fuse F39 5 amp in the left foot well fuse holder, and the Yellow wire should have battery voltage from the D+ circuit on the alternator with the engine running.
If the three power inputs and the ground are good, and the pump does not operate, the pump is defective. Also make sure that the cooling fan for the EHPS, mounted under the pump, comes on when the radiator cooling fan does.
I hope this information is helpful to you.
Should you have any questions please let me know.
Thanks so much.