DTC B1877, B1878, B1879, B1885

id080200801400

DTC

B1877

Driver-side pre-tensioner seat belt system resistance high

B1878

Driver-side pre-tensioner seat belt system circuit short to power supply

B1879

Driver-side pre-tensioner seat belt system circuit short to ground

B1885

Driver-side pre-tensioner seat belt system resistance low

DETECTION CONDITION

Warning
• Detection conditions are for understanding the DTC outline before performing an inspection. Performing an inspection with only detection conditions may cause injury due to an operating error, or damage the system. When performing an inspection, always follow the inspection procedure.
• Resistance other than 1.5-3.1 ohm detected in driver-side pre-tensioner seat belt circuit
• Malfunction in the wiring harness between driver-side pre-tensioner seat belt and SAS control module

POSSIBLE CAUSE

• Open or short circuit in wiring harness between driver-side pre-tensioner seat belt and SAS control module
• Driver-side pre-tensioner seat belt malfunction
• SAS control module malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT DRIVER-SIDE PRE-TENSIONER SEAT BELT
• Using the WDS or equivalent, verify the following PID/DATA monitor.
- D_PTENSFLT
• Is the resistance of the driver-side pre-tensioner seat belt normal?
- Resistance: 1.5-3.1 ohm
Yes
Replace the SAS control module.
No
Go to the next step.
2
INSPECT DRIVER-SIDE PRE-TENSIONER SEAT BELT CONNECTOR
Warning
• Handling the air bag system components improperly can accidentally deploy the air bag modules and pre-tensioner seat belts, which may seriously injure you. Read the service warnings and cautions before handling the air bag system components.
(See SERVICE WARNINGS.)
(See SERVICE CAUTIONS.)
• Turn ignition switch to LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Remove driver's side B-pillar lower trim.
• Disconnect the driver-side pre-tensioner seat belt connector.
• Is there any malfunction of the driver-side pre-tensioner seat belt connector?
Yes
Replace the air bag wiring harness.
No
Go to the next step.
3
VERIFY WHETHER MALFUNCTION IS IN DRIVER-SIDE PRE-TENSIONER SEAT BELT OR RELATED WIRING HARNESS
• Connect leads of SST (Fuel and thermometer checker) or apply 2-ohm resistor to driver-side pre-tensioner seat belt connector terminal A and B.
• Set resistance of SST (Fuel and thermometer checker) to the 2-ohm position.
• Connect the negative battery cable.
• Turn the ignition switch to ON position.
• Are DTCs B1877, B1878, B1879, and/or B1885 indicated?
Yes
Go to the next step.
No
Replace the driver-side pre-tensioner seat belt.
4
INSPECT WIRING HARNESS BETWEEN DRIVER-SIDE PRE-TENSIONER SEAT BELT MODULE AND SAS CONTROL MODULE
• Turn the ignition switch to the LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Disconnect the driver and passenger-side front seat connectors.
• Disconnect the driver and passenger-side curtain air bag module connectors.
• Turn up floor covering.
• Inspect the wiring harness between SAS control module terminal 2S and driver-side pre-tensioner seat belt terminal A, SAS control module terminal 2P and driver-side pre-tensioner seat belt terminal B for the following:
- Short to ground
- Short to power supply
- Open circuit
• Is the wiring harness normal?
Yes
Replace the SAS control module.
No
Replace the air bag wiring harness.