X74 - Check Fuel Pump Circuit For Short to Power
- Key "OFF".
- Breakout box installed, Powertrain Control Module (PCM) disconnected.
- Constant Control Relay Module (CCRM) disconnected.
- Key "ON".
- Measure voltage between test pin 22 and the battery negative post.
- Is voltage less than 1.0 volt?
Yes -- Go to X75. X75 - Check Fuel Pump Circuit For Short to Ground
No -- Service short to power. Remove breakout box. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)
If Diagnostic Trouble Code (DTC) 556/557 is still present, replace PCM.