Test T: DTC B1870 - Air Bag Indicator Shorted to Battery

T1 - T2:

T3 - T4:

T5:

Normal Operation
The air bag indicator is designed to illuminate for 6 (±2) seconds when the ignition switch is turned to the RUN position. This initial 6 seconds of illumination is considered normal operation and is called proveout of the air bag indicator. The air bag indicator is then used to warn the driver that there is a fault in the air bag Supplemental Restraint System (SRS).

While the air bag indicator is lit the Restraints Control Module (RCM) monitors the air bag indicator for short to battery conditions. If the RCM detects a short to battery condition on the air bag indicator circuit, it will store a Diagnostic Trouble Code (DTC) B1870 in memory.

If the RCM detects an air bag indicator failure in addition to another SRS failure, the RCM will send a signal to the Generic Electronic Module (GEM) to produce five sets of five tone bursts.

Possible Causes
An air bag indicator short to battery condition could be caused by:
^ a short to battery on circuit 608 (BK/YE).
^ a worn or damaged instrument cluster.