FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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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)