The inflatable restraint steering wheel module deployment loop consists of a steering wheel module, steering wheel module coil, steering wheel module high signal circuit, and steering wheel module low signal circuit. Shorting bars are used on the steering wheel module connector as well as the steering wheel module coil connector which will short together the steering wheel module high and steering wheel module low signal circuits when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing. When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored.
Ignition 1 voltage is within the normal operating voltage range.
• | The SDM detects the steering wheel module deployment loop resistance is greater than 4.8 ohms for 500 milliseconds. |
• | The SDM detects the voltage at steering wheel module high signal is less than 2.4 volts and steering wheel module high to steering wheel module low signal resistance is 6 ohms or greater for 500 milliseconds. |
The SDM commands ON the AIR BAG indicator via Class 2 serial data.
• | The condition responsible for setting the DTC no longer exists. |
• | You issue a scan tool CLEAR DTCs command. |
• | A history DTC will clear once 255 malfunction free ignition cycles have occurred. |
The following can cause an intermittent condition:
• | A short between the steering wheel module high and steering wheel module low signal circuits |
• | A malfunctioning shorting bar on the steering wheel module connector |
• | A malfunctioning shorting bar on the steering wheel module coil connector |
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
The numbers below refer to the step numbers on the diagnostic table.
This step inspects the steering wheel module coil in-line connector.
Tests for proper operation of the steering wheel module coil and/or steering wheel module.
Tests for an open or high resistance in the steering wheel module high and steering wheel module low signal circuits.
Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
Schematic Reference: SIR Schematics | |||||||||
1 | Did you perform A Diagnostic System Check - SIR? | Go to Step 2 | |||||||
Do the connectors exhibit any signs of corrosion, terminal damage, or poor connections? | Go to Step 3 | Go to Step 4 | |||||||
3 |
Did you complete the replacement? | Go to Step 12 | -- | ||||||
4 |
Does the scan tool indicate that DTC B0026 is current? | Go to Step 5 | Go to Diagnostic Aids | ||||||
5 |
Does the scan tool indicate that DTC B0026 is current? | Go to Step 7 | Go to Step 6 | ||||||
Does the scan tool indicate that DTC B0026 is current? | Go to Step 10 | Go to Step 11 | |||||||
7 |
Did you find and correct the condition? | Go to Step 12 | Go to Step 8 | ||||||
Test the steering wheel module high and steering wheel module low signal circuits for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 9 | |||||||
9 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you complete the replacement? | Go to Step 12 | -- | ||||||
10 | Replace the steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement . Did you complete the replacement? | Go to Step 12 | -- | ||||||
11 | Replace the steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement . Did you complete the replacement? | Go to Step 12 | -- | ||||||
12 |
Does the DTC reset? | Go to Step 2 | System OK |