When you first turn ON the ignition, the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM) performs tests to diagnose critical malfunctions within itself. Then, the SDM proceeds with the RESISTANCE MEASUREMENT test to measure the deployment loop resistances to ensure that they are within their respective normal resistance ranges. During one portion of the RESISTANCE MEASUREMENT test, the SDM does the following:
• | Measures the voltage difference between the driver belt high and driver belt low circuits |
• | Uses the measured voltage to calculate the resistance of the driver seat belt pretensioner deployment loop |
Upon passing these tests, the energy reserve is charged and the firing transistors are tested. The SDM then goes into the CONTINUOUS MONITORING mode.
When the ignition voltage is within the normal operating voltage range, the SDM performs the RESISTANCE MEASUREMENT test in order to calculate the resistance of the driver seat belt pretensioner deployment loop.
The calculated resistance of the driver seat belt pretensioner deployment loop is above 2.5 ohms.
The SDM turns ON the AIR BAG warning lamp.
• | You can issue a CLEAR CODES command |
• | A history DTC will clear once 255 malfunction free ignition cycles have occurred. |
The following can cause an intermittent condition:
• | The driver seat belt pretensioner 2-way connector. |
• | The SDM wiring harness connector. |
• | The wire to terminal connections in the driver belt high circuit. |
• | The wire to terminal connections in the driver belt low circuit. |
• | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
The numbers below refer to step numbers on the diagnostic table.
This step checks the driver seat belt pretensioner 2-way connector.
This step checks the SDM wiring harness connector.
This step checks for an open or a high resistance in the driver belt high circuit.
This step determines if there is an open or a high resistance in the driver belt low circuit or if there is a malfunctioning SDM.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform A Diagnostic System Check - SIR? | -- | Go to Step 2 | |||||||
Does either the male or female sides of the inline connector exhibit signs or corrosion, terminal damage, or poor connections? | -- | Go to Step 3 | Go to Step 4 | |||||||
3 |
Did you complete the repair? | -- | Go to Step 14 | -- | ||||||
4 |
Does the scan tool indicate that this DTC is current? | -- | Go to Step 5 | Go to Diagnostic Aids | ||||||
5 |
Does the scan tool indicate that the LH PRETENS. RES. is greater than the specified value? | 2.5 ohms | Go to Step 7 | Go to Step 6 | ||||||
6 |
Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||
Does the SDM wiring harness connector exhibit any signs of corrosion, terminal damage, or poor connections? | -- | Go to Step 8 | Go to Step 9 | |||||||
8 | Replace the SDM wiring harness connector. Refer to Connector Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||||
Does the resistance measure less than the specified value? | 0.5 ohms | Go to Step 11 | Go to Step 10 | |||||||
10 | Locate and repair an open or a high resistance in the driver belt high circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||||
Use the DMM to measure the resistance of the driver belt low circuit. Does the resistance measure less than the specified value? | 0.5 ohms | Go to Step 13 | Go to Step 12 | |||||||
12 | Locate and repair an open or a high resistance in the driver belt low circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||||
13 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic and Seat Belt Pretensioner Module Replacement . Did you complete the repair? | -- | Go to Step 14 | -- | ||||||
14 |
Did you complete the action? | -- | -- |