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For 1990-2009 cars only

DTC B0045 Coupe


Object Number: 864406  Size: MF

Circuit Description

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 deployment loop high circuit and deployment loop low circuit voltage difference. By monitoring voltage, the SDM is able to detect when loop voltage is not between 2.4 and 6.0 volts.

DTC Parameters

DTC B0045 can be set when the loop voltage is out of range. The following conditions must be met to set this DTC:

    • Ignition voltage is present at the SDM and continuous.
    • The deployment loop voltage is over 6 volts OR under 2.4 volts with deployment loop resistance under 6 ohms.
    • Fault is present for half a second.

Action Taken

    • DTC B0045 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 the scan tool.
    • Always start diagnosis of SIR DTCs with an inspection of wiring and components for visible damage.
    • A short to ground in circuits 2137 or 2138 could cause this DTC.
    • A short between circuits 2137 or 2138 and another vehicle circuit could cause this DTC.
    • Always perform the Diagnostic System Check - SIR procedure before using this chart.

Object Number: 876204  Size: FP

Object Number: 876206  Size: FP

DTC B0045 Sedan


Object Number: 864421  Size: MF

Circuit Description

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 deployment loop high circuit and deployment loop low circuit voltage difference. By monitoring voltage, the SDM is able to detect when loop voltage is not between 2.4 and 6.0 volts.

DTC Parameters

DTC B0045 can be set when the loop voltage is out of range. The following conditions must be met to set this DTC:

    • Ignition voltage is present at the SDM and continuous.
    • The deployment loop voltage is over 6 volts OR under 2.4 volts with deployment loop resistance under 6 ohms.
    • Fault is present for half a second.

Action Taken

    • DTC B0045 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 the scan tool.
    • Always start diagnosis of SIR DTCs with an inspection of wiring and components for visible damage.
    • A short to ground in circuits 2137 or 2138 could cause this DTC.
    • A short between circuits 2137 or 2138 and another vehicle circuit could cause this DTC.
    • Always perform the Diagnostic System Check - SIR procedure before using this chart.

Object Number: 876204  Size: FP

Object Number: 876206  Size: FP