XB150 - Continuous Code 524/543/556: Is Cont Code 583 Present

Continuous Memory Diagnostic Trouble Codes (DTC) 524/543 indicate that sometime during vehicle operation, when the Powertrain Control Module (PCM) commanded the fuel pump on, voltage was not detected on the power-to-pump circuit (through Fuel Pump Monitor (FPM), PCM Pin 8). Although DTC 524 refers to the low speed output (VCRM Pin 24) and DTC 543 refers to the high speed output, it is not possible to distinguish between circuits due to the vehicle wiring and fuel pump operating strategy.

Possible causes:

- Open in power-to-pump circuit between the VCRM and FPM splice.

- Open in B(+) supply to VCRM (Pins 4 and 5).

- Left Heated Oxygen Sensor (HO2S) short to power.

Continuous Memory DTC 556 indicates that sometime during vehicle operation, a fuel pump primary circuit failure occurred.

Possible causes:

- Open or short in Fuel Pump (FP) circuit (PCM Pin 22).

- Is Continuous Memory DTC 583 also present?

Yes -- Continuous DTC 583 indicates that an over current (short to ground) occurred on power-to-pump/FPM circuit. This could also result in DTCs 524/543 being set. Go to XB136. XB136 - Clear and Attempt to Regenerate Code 583

No -- Go to XB151. XB151 - Check Power to Pump and FP Circuits