Possible Causes

A passenger-side air bag circuit shorted to ground could be caused by damaged wiring, terminals or connectors, short to ground in passenger-side air bag module or faulty RCM.

1. Check for hard or intermittent DTC
   
   Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Turn ignition switch to ON position. Retrieve and record any continuous DTCs. See RETRIEVING FAULT CODES  under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST  under DIAGNOSTICS. If DTC B1938 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B1938 was not retrieved, fault is intermittent. Go to step  5 .
2. Check passenger-side air bag module
   
   Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Turn ignition switch to RUN position. Perform on-demand self-test. See ON-DEMAND SELF-TEST  under DIAGNOSTICS. If DTC B1938 is retrieved, go to next step. If DTC B1938 is not retrieved, fault is intermittent. Attempt to recreate fault by flexing wire harness and cycling ignition frequently. See WIRING DIAGRAMS  . Repair any intermittent problems found. Go to step  6 .
   NOTE: Do not remove or separate shorting bars from RCM harness connector.
3. Check passenger-side air bag circuit
   
   Turn ignition switch to OFF position. Disconnect passenger-side air bag simulator from harness connector. Access RCM and disconnect harness connector C310A. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Turn ignition switch to RUN position. Measure resistance between ground and harness side of RCM connector C310A, terminals No. 3 (Light Blue/Orange wire) and No. 4 (Pink/Black wire). See Figure . If resistance is more than 10 k/ohms in both circuits, go to next step. If resistance is less than 10 k/ohms in either circuit, repair short to ground in appropriate wire. Go to step  6 .
   NOTE: Ensure all air bag system simulators, sensor electrical connectors and RCM electrical connectors are connected prior to carrying out on-demand self-test, or erroneous faults may be set.
4. Confirm RCM fault
   
   Turn ignition switch to OFF position. Reconnect RCM connector C310A. Reconnect passenger-side air bag module harness connector. Turn ignition switch to ON position. Perform on-demand self-test. If DTC B1938 was retrieved during on-demand self-test, replace RCM. Go to step  6 . If DTC B1938 was not retrieved during on-demand self-test, fault is intermittent. Attempt to recreate fault by flexing wire harness and cycling ignition frequently. See WIRING DIAGRAMS  . Activate other systems in same wire harness. Repair any intermittent problems found. Go to step  6 .
5. Check for intermittent fault
   
   Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Perform on-demand self-test. If DTC B1938 was retrieved during on-demand self-test, check for cause of intermittent fault at or near air bag module harness connector. See WIRING DIAGRAMS  . Repair any intermittent faults found. If intermittent faults are found and corrected, go to next step. If intermittent faults are not found, go to step  3 . If DTC B1938 was not retrieved during on-demand self-test, attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Activate other systems in same wire harness. Repair any intermittent problems found. Go to next step.
6. Check for additional DTCs
   
   Refer to continuous DTCs recorded in step  1 . If any continuous DTCs were retrieved, go to diagnostic trouble code identification table for direction to appropriate test. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table. DO NOT clear any DTCs until all DTCs have been resolved. If no continuous DTCs were retrieved, reconnect air bag system. Activate air bag system. See ACTIVATING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS.