Steering Mounted Controls Communication Module: Testing and Inspection

MODULE-STEERING CONTROL

WARNING: TO AVOID PERSONAL INJURY OR DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE SUPPLEMENTAL RESTRAINT SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, AIRBAG, OCCUPANT CLASSIFICATION SYSTEM, SEAT BELT TENSIONER, IMPACT SENSOR, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE WAY TO DISABLE THE SUPPLEMENTAL RESTRAINT SYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT.

The hard wired inputs and outputs of the Steering Control Module (SCM) and the external switch components may be diagnosed and tested using conventional diagnostic tools and procedures. Refer to the appropriate wiring information and the procedures for the individual switches. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods may not prove conclusive in the diagnosis of the SCM, the Controller Area Network (CAN) data bus, or the electronic message outputs used to communicate the status of the internal and external switch inputs to the SCM. The most reliable, efficient, and accurate means to diagnose the SCM, the CAN data bus and the electronic message outputs for the SCM requires the use of a diagnostic scan tool.