X21 - Check VPWR Circuit To CCRM
- Key "OFF".
- Disconnect Constant Control Relay Module (CCRM).
- Disconnect EEC-IV power relay.
EEC-IV Power Relay Connector:
- Measure resistance between Pin 13 at the CCRM vehicle harness connector and the VPWR circuit at the EEC-IV power relay vehicle harness connector.
- Is resistance less than 5.0 ohms?
Yes -- Reconnect EEC-IV power relay. Go to X22. X22 - Check FC/LFC Circuit For Short to Ground
No -- Service open VPWR circuit between the EEC-IV Power Relay and the CCRM. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)