Test Ff: Step 11

11) Check For PSPS Always Open Compared to Hydraulic Pressure With Engine Running  At this point, there are only 2 possible causes for original KOER Code 52. They are a PSPS switch that is always open, or excessively high hydraulic pressure. Turn key off and wait 10 seconds. Substitute original PSPS with a known good PSPS. Perform KOER Self-Test and turn steering wheel at least 1/2 turn after engine ID code. If Code 52 is still present, check power steering system for excessive hydraulic pressure. If Code 52 is not present, replace original PSPS switch. Service other codes if necessary.