Possible Causes
WARNING: This page is about a different car, the 2003 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
No communication with RCM condition could be caused by damaged Light Blue/White wire, damaged DLC, damaged scan tool or RCM internal fault.
- Check RCM connector & pin for damage
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access RCM and disconnect harness connector C2041A. See RESTRAINTS CONTROL MODULE (RCM) under REMOVAL & INSTALLATION. Inspect RCM connector, terminal No. 5 (Light Blue/White wire), component side and harness side, for damage. See Figure & Figure . If module pin and module harness connector C2041A, terminal No. 5 are okay, go to next step. If module pin and module harness connector C2041A, terminal No. 5 are damaged, repair/replace as necessary. Activate air bag system. See ACTIVATING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. - Check DLC for damage
Inspect Data Link Connector (DLC) and DLC connector terminal No. 7 (Light Blue/White wire) for damage. See Fig 1 . DLC is located under center of instrument panel. If DLC connector and DLC connector terminal No. 7 (Light Blue/White wire) is okay, go to next step. If DLC connector and DLC connector terminal No. 7 (Light Blue/White wire) is damaged, repair/replace Light Blue/White wire or connector as necessary. See WIRING DIAGRAMS . Reactivate air bag system. - Check circuit for short to battery
Measure voltage on Light Blue/White wire between ground and DLC connector terminal No. 7. If measurable voltage is detected, repair short to battery on Light Blue/White wire. Reactivate air bag system. If measurable voltage is not detected, go to next step. - Check circuit for open
Measure resistance of Light Blue/White wire (circuit No. 70) between RCM connector C2041A, terminal No. 5 and DLC connector terminal No. 7. See Figure & Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire. Reactivate air bag system. - Check circuit for short to ground
Measure resistance on Light Blue/White wire between ground and DLC connector terminal No. 7. If resistance is less than 10 k/ohms, repair short to ground on Light Blue/White wire. Reactivate air bag system. If resistance is more than 10 k/ohms, replace RCM. Reactivate air bag system.