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X141 - Verify Operation of Both HFC Relays In CCRM



- Key "OFF".

- Constant Control Relay Module (CCRM) disconnected.

- Connect a jumper wire between Pin 13 of the CCRM and the battery positive (+) post.

- Connect another jumper wire between Pin 17 of the CCRM and the battery negative (-) post.

- Measure resistance between Pin 10 and both Pins 12 and 24.

- Measure resistance between Pin 4 and both Pins 1 and 2.

- Are all resistances less than 5.0 ohms?

Yes -- Both High Fan Control (HFC) relays are OK. Remove jumpers After original service, reconnect all components. Re-evaluate symptom.

No -- Replace CCRM. After also performing original service, reconnect all components. Re-evaluate symptom.