Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Test C

PINPOINT TEST C: DTC B1870 - AIR BAG WARNING INDICATOR CIRCUIT SHORT TO BATTERY


Test C1-C2:






Test C2-C3:






Test C4-C5:






Normal Operation
During normal operation, the air bag indicator will illuminate continuously for approximately 6 seconds and then go out after the ignition switch is placed in the ON or START position and no air bag fault exist. The air bag indicator will remain illuminated continuously after five cycles of a lamp fault code (LFC), if a fault exist.

If the restraints control module detects a short to battery on the air bag warning indicator circuit, it will store diagnostic trouble code (DTC) B1870 in memory. If any other DTCs are active with this DTC, the secondary air bag warning chime will be activated.

Possible Causes
An air bag indicator circuit short to battery can be caused by:
- faulted wiring, terminals, or connectors.
- a faulted instrument cluster module.
- a faulted RCM.