B0029
CIRCUIT DESCRIPTIONSchematic:
When the ignition switch is turned On and during vehicle operation, the SDM performs tests to detect system faults. One test the SDM performs is to monitor the inflator module high circuit and inflator module low circuit voltage difference. By monitoring voltage difference, the SDM is able to calculate the loop resistance. High resistance indicates an open somewhere in the deployment loop.
DTC PARAMETERS
DTC B0029 can be set when the loop resistance is high. The following conditions must be met to set this DTC:
^ Ignition voltage is present at the SDM and continuous.
^ The deployment loop resistance is over 4.8 ohms or circuit 2135 under 2.4 volts with deployment loop resistance over 6 ohms.
^ Fault is present for half a second.
ACTION TAKEN
^ DTC B0029 will set.
^ The air bag telltale will be On.
DIAGNOSTIC AIDS
^ When attempting to diagnose an intermittent loop fault, use the Scan tool to monitor current DTCs. Wiggle wires and check connections while watching for a current DTC to appear and/or disappear on Scan tool.
^ Always start diagnosis of SIR DTCs with an inspection of wiring and components for visible damage.
^ An open in circuits 2135 or 2136 to the inflator module could cause this DTC.
^ Always perform the "SIR Diagnostic System Check" before using this chart. Diagnostic System Check
TEST DESCRIPTION
