Circuit/System Testing
When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling. Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs.
Refer to SIR Disabling and Enabling
Refer to SIR Service Precautions
It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.
The connector position assurance (CPA) should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly.
- Ignition/Vehicle & All vehicle systems - Off
- Disconnect the electrical connector: X1 & X2 @ K36 Inflatable Restraint Sensing and Diagnostic Module & B88P Seat Belt Switch - Passenger
- Ignition - On / Vehicle - In Service Mode
- Test for less than 0.3 V between the test points: Signal circuit terminal 11 X315 @ Component harness & Ground
- If greater than 0.3 V
Repair the short to voltage on the circuit.
- Go to next step: If less than 0.3 V
- If greater than 0.3 V
- Ignition/Vehicle - Off
- Test for infinite resistance between the test points: Signal circuit terminal 11 X315 @ Component harness & Ground
- If less than infinite resistance
Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- If less than infinite resistance
- Ignition - On / Vehicle - In Service Mode
- Test for less than 0.3 V between the test points: Low Reference circuit terminal 12 X315 @ Component harness & Ground
- If greater than 0.3 V
Repair the short to voltage on the circuit.
- Go to next step: If less than 0.3 V
- If greater than 0.3 V
- Ignition/Vehicle - Off
- Test for infinite resistance between the test points: Low Reference circuit terminal 12 X315 @ Component harness & Ground
- If less than infinite resistance
Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- If less than infinite resistance
- Test for less than 2 ohms between the test points: Signal circuit terminal 11 X315 @ B88P Seat Belt Switch - Passenger & Terminal 45 X2 @ K36 Inflatable Restraint Sensing and Diagnostic Module
- If greater than 2 ohms
Repair the open/high resistance in the circuit.
- Go to next step: If less than 2 ohms
- If greater than 2 ohms
- Test for less than 2 ohms between the test points: Low Reference circuit terminal 12 X315 @ B88P Seat Belt Switch - Passenger & Terminal 44 X2 @ K36 Inflatable Restraint Sensing and Diagnostic Module
- If greater than 2 ohms
Repair the open/high resistance in the circuit.
- Go to next step: If less than 2 ohms
- If greater than 2 ohms
- Test for infinite resistance between the test points: Signal circuit terminal 11 X315 & Low Reference circuit terminal 12 X315 @ Component harness
- If less than infinite resistance
Repair the short between the circuits: Signal circuit terminal 11 X315 & Low Reference circuit terminal 12 X315
- Go to next step: If infinite resistance
- If less than infinite resistance
- Replace the component: B88P Seat Belt Switch - Passenger
- Verify the DTC does not set.
- If the DTC is set
Replace the component: K36 Inflatable Restraint Sensing and Diagnostic Module
- Go to next step: If the DTC is not set
- If the DTC is set
- All OK.