OEM 2004 Mercury Mountaineer Air Bag Control Module

2004 Mercury Mountaineer Air Bag Control Module Parts Q&A

• Q: How to Service and Repair the Air Bag Control Module on 2004 Mercury Mountaineer?

  A: Service and repair operations of the Restraints Control Module (RCM) must start with depowering the system by turning OFF the ignition switch to avoid accidental safety canopy deployment which threatens injury to personnel. The position of the RCM must stay horizontal during service to provide correct functioning for the air bag supplemental restraint system (SRS). Before any service or repair of the RCM begins testing should be performed to check for deformation on the mounting and bracket system; a complete replacement of the RCM is necessary even without air bag deployment. Check the sensor mounting bracket together with the wiring pigtail for signs of damage then replace all components of the SRS system that show any kind of deformation. Correct system operation requires proper tightening of RCM retaining nuts while safety glasses need to be worn as a protective measure during repairs. The use of memory saver devices should be avoided because they raise personal injury risks. You should note that the air bag warning lamp will turn on if you pull out the RCM fuse when the ignition is on though this condition does not signify a fault. A fully functional SRS testing should occur before the vehicle returns to the customer for any service. Check the accuracy of new RCM parts because incorrect fitments might trigger erroneous diagnostic trouble codes (DTCs) in the system. The repairs require installation of new elements but if problems remain the original part must be reinstalled followed by another diagnostic test. The first step to remove the RCM is disconnecting its large electrical connector through a combination of pressuring the thumb tab while pushing back the connector position assurance lever then extracting the connector. The installation process should start with continuous battery negative cable disconnection followed by a backward execution of the removal process. To properly link the large RCM electrical connector users should unlock the connector position assurance lever entirely before positioning and gently guiding the connector until it produces an audible clicking sound. The connector position assurance lever must be pivoted toward the RCM to lock in the connection after making sure the thumb tab becomes engaged.