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Body Control Module (BCM) Diagnostic System Check

  1. Ensure battery condition, cold cranking amperage and reserve capacity meet specifications. Replace as necessary. Install scan tool to Data Link Connector (DLC). If scan tool powers up, go to next step. If scan tool does not power up, go to SCAN TOOL DOES NOT POWER UP  .
  2. Turn ignition on, engine off. Try to establish scan tool communication with BCM. If communication with BCM is established, go to next step. If communication with BCM is not established, go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE.
  3. Select display DTC function for BCM. Record all displayed DTCs and status of displayed DTCs. If DTCs are displayed, go to next step. If no DTCs are displayed, attempt to diagnose malfunctioning system or device by symptom. Go to appropriate article for malfunctioning system or device.
  4. If scan tool displays any DTCs that begin with "U", go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE. If scan tool displays DTCs that begin with "B", go to BODY CONTROL MODULE (BCM) DTC DEFINITIONS  table. If scan tool does not display DTCs with "B" or "U", go to system in which customer concern is addressed.
BODY CONTROL MODULE (BCM) DTC DEFINITIONS

DTC (1) Module Description
B1552  BCM Loss Of BCM Keep Alive Memory (KAM)
B1556  BCM BCM EEPROM Write Error
B1558  BCM BCM EEPROM Checksum Error
B1656  Radio Radio EEPROM Write Error
B1658  Radio Radio EEPROM Checksum Error
B1760  Radio CD Changer Not Responding
B1780  Radio Theft Lock Enabled
B1970  BCM Exterior Light Power Fault
B1971  BCM Inadvertent Power Fault
B1973  BCM High Power Control Fault
B1982  BCM Battery Voltage Too High
B1982  Radio Battery Voltage Too High
B1983  BCM Battery Voltage Too Low
B1983  Radio Battery Voltage Too Low
B2462  RIM GPS Signal Error
B2470  BCM Daytime Running Lights Fault
B2471  BCM Interior Lights Fault
B2472  BCM Low Beam Fault
B2473  BCM High Beam Fault
B2476  BCM Parking Lights Fault
B2476  Radio Cellular Phone Select Service Switch Malfunction
B2556  BCM EEPROM Error
B2560  BCM Remote Keyless Entry (RKE) Message Validation Error
U1300  BCM, IRC Class 2 Short To Ground
U1301  BCM, IRC Class 2 Short To Battery
U2100  EBTCM, ECM, TCM CAN-BUS Communication Malfunction
U2103  EBTCM, ECM Fewer Controllers On Bus Than Programmed
U2104  EBTCM, ECM, TCM CAN Bus Reset Counter Overrun
U2105  EBTCM, TCM Lost Communication With Engine Control Module (ECM)
U2106  EBTCM, ECM Lost Communication With Transmission Control System (TCM)
U2108  ECM, TCM Lost Communication With ABS Control System (EBTCM)
(1) For DTCs beginning with "C", perform diagnostic system check in appropriate article in BRAKES. For DTCs beginning with "P", perform OBD diagnostic system check in appropriate article in ENGINE PERFORMANCE. For DTCs not listed, See system in which customer concern is apparent.