B1B12
B1B12 - Driver Knee Bolster Squib Circuit Open
For a complete wiring diagram, refer to.
Theory of Operation
When powered, the Occupant Restraint Controller (ORC) sends a test current to the squibs to verify the integrity of the squib and wiring. These circuits are maintained in a "floating" configuration at the module (connected to neither power nor ground) as protection against inadvertent deployment. Use of the SRS Load Tool Kit 8443A in the tests below substitutes a suspect squib with a known good component. The use of the SRS Load Tool adapter provides a test point as well as a method for opening the shorting bar connections within the harness connector.
• When Monitored: The ORC Module sends out a 40 mA diagnostic current on each squib voltage supply circuit at power up, and every 500 ms thereafter while the ignition is on.
• Set Condition: This Diagnostic Trouble Code (DTC) sets when the ORC detects an open on the driver knee bolster squib circuit for more than 2.5 seconds. This DTC transitions from active to stored when the ORC sees a recovery from a short to ground for greater than 2.5 seconds.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Test Step 1 - DETERMINE ACTIVE OR STORED DTC
• Make sure that the battery is fully charged.
• The scan tool, SRS Airbag Load Tool Kit 8443A, and DVOM are required to perform the following test.
• Turn the ignition on.
Select ACTIVE or STORED DTC:
ACTIVE DTC
• Go to Test Step 2 => [ Test Step 2 - CHECK FOR OPEN DRIVER KNEE BOLSTER AIRBAG CIRCUITS ]
STORED DTC
• Perform the Restraints System Intermittent Test. Refer to => Non - DTC Based Diagnostics. ORC Restraints System Intermittent Test
Test Step 2 - CHECK FOR OPEN DRIVER KNEE BOLSTER AIRBAG CIRCUITS
Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
• Disconnect the Driver Knee Bolster Airbag harness connector.
• Check connectors - Clean and repair as necessary.
• Connect the SRS Load Tool Kit 8443A to the SRS Load Tool Jumper 8443-8 to the Driver Knee Bolster Airbag harness connector.
Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
• With the scan tool, read the active ORC DTCs.
Does the scan tool display: B1B12-DRIVER KNEE BOLSTER SQUIB CIRCUIT OPEN?
Yes
• Go to Test Step 3 => [ Test Step 3 - CHECK (R11) DRIVER KNEE BLOCKER SQUIB LINE 1 CIRCUIT
FOR AN OPEN ]
No
• Replace the Driver Knee Bolster Airbag.
• Perform the Restraints System Verification Test. Refer to => Non - DTC Based Diagnostics. ORC Restraints System Verification Test
Test Step 3 - CHECK (R11) DRIVER KNEE BLOCKER SQUIB LINE 1 CIRCUIT FOR AN OPEN
Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
• Disconnect the SRS Load Tool Kit 8443A from the SRS Load Tool Jumper 8443-8 from the Driver Knee Bolster Airbag harness connector.
• Disconnect the ORC harness connectors.
• Check connectors - Clean and repair as necessary.
• Connect the SRS Load Tool adapter 8443-28 to the ORC C2 harness connector.
• Measure the resistance of the (R11) Driver Knee Blocker Squib Line 1 circuit between the Driver knee Bolster Airbag harness connector and the appropriate terminal of the SRS Load Tool adapter 8443-28.
Is the resistance below 1.0 Ohm?
Yes
• Go to Test Step 4 => [ Test Step 4 - CHECK (R9) DRIVER KNEE BLOCKER SQUIB LINE 2 CIRCUIT
FOR AN OPEN ]
No
• Repair the (R11) Driver Knee Blocker Squib Line 1 circuit for an open in accordance with the Service Information.
• Perform the Restraints System Verification Test. Refer to => Non - DTC Based Diagnostics. ORC Restraints System Verification Test
Test Step 4 - CHECK (R9) DRIVER KNEE BLOCKER SQUIB LINE 2 CIRCUIT FOR AN OPEN
• Measure the resistance of the (R9) Driver Knee Blocker Squib Line 2 circuit between the Driver Knee Bolster Airbag harness connector and the appropriate terminal of the SRS Load Tool adapter 8443-28.
Is the resistance below 1.0 Ohm?
Yes
• Replace the ORC..
• Perform the Restraints System Verification Test. Refer to => Non - DTC Based Diagnostics. ORC Restraints System Verification Test
If the Occupant Restraint Controller (ORC) is dropped at any time, it must be replaced. Failure to follow these instructions may result in possible serious or fatal injury.
No
• Repair the (R9) Driver Knee Blocker Squib Line 2 circuit for an open in accordance with the Service Information.
• Perform the Restraints System Verification Test. Refer to => Non - DTC Based Diagnostics. ORC Restraints System Verification Test