Capacitance Too Low
Capacitance too low. Permanent fault
Checking the component
- Ignition off
- Disconnect the (green) connector from the airbag on the driver's side
- Connect special tool951 1506 Test dummy 951 1506 Test Dummy to the airbag connector (green) on the driver's side
Warning! Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected, non-deployed, pyrotechnical airbag. This could deploy the airbag!
Note! The special tool must be checked and fault-free. If the tool is defective, the diagnosis readings will be incorrect. This will make fault-tracing harder.
- Switch on the ignition. Wait 10 seconds.
Read off diagnostic trouble codes (DTCs).
Try a new airbag on the driver's side if the diagnostic trouble code (DTC) changes status from a permanent to an intermittent fault.
Other information:
- To access and replace the airbag on the driver's side, see Airbag driver's side (SRS), replacing Airbag Driver's Side (SRS), Replacing
- To check the special tool, see Calibration Calibrating the Special Tool.
Does the status of the diagnostic trouble code (DTC) change?
Yes - Verification
No - Checking components and wiring
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Checking components and wiring
- Ignition off
- Disconnect special tool951 1506 Test dummy 951 1506 Test Dummy from the airbag connector (green) on the driver's side.
Warning! Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected, non-deployed, pyrotechnical airbag. This could deploy the airbag!
Caution! Do not touch the terminal pins in the SRS control module. There is a risk of static discharge. This could damage the SRS control module.
Disconnect the connector from:
- the SRS control module
- the contact reel.
Check the cable terminals in the female and male sections of the connector. The cable terminals must not be damaged or pressed back.
Check the cable between SRS control module terminals #8B (36) and #7B (35) and driver's airbag connector (green) terminals #1 and #3 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Hint: Check the integrated capacitor in the igniter connector: Measure the resistance.
With the ignition off, connect the test instrument probes between terminals #1 and #3 on the driver's airbag connector (green). The ohmmeter reading should rise rapidly to infinity.
Reverse the position of the ohmmeter positive and negative test probes. Connect them to the connector as in the previous measurement. The ohmmeter reading should drop rapidly to approximately 0 ohms and then increase to infinity.
Disconnect the connector from the contact reel. Check the contact reel wiring by connecting an ohmmeter between terminals #1 and #2 (driver's airbag side) and driver's airbag connector terminals #1 and #3. The ohmmeter should read approximately 0 ohms. Take the readings again while turning the steering slowly to full lock in each direction. The ohmmeter should read approximately 0 ohms for all positions for the steering wheel.
Remedy as necessary.
Other information:
- To access and replace the SRS control module connector, see Control module SRS (supplemental restraint system), replacing Service and Repair
- To access the connector for the driver's airbag, see Airbag driver's side (SRS), replacing Airbag Driver's Side (SRS), Replacing
- To access and replace the contact reel, see Contact reel / steering wheel angle sensor, replacing Contact Reel / Steering Wheel Angle Sensor, Replacing
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box, Supplemental Restraint System Module (SRS)
- With the ignition off and the contact reel connector disconnected, the resistance between terminals #1 and #2 on the contact reel connector (SRS control module side) should be approximately 22 kohms.
- For information about the repair of SRS wiring, see Cable harness SRS system, repair Procedures
- For other values, see Signal specification Signal Specification, Supplemental Restraint System Module (SRS).
Continue - Verification
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Verification
Verification
Verification
Hint: After carrying out the repair, check that the fault has been remedied.
- Ignition off
- Disconnect the battery negative lead
- Reinstall the connectors, components etc.
- Ignition on
- Connect the battery negative lead.
Warning! There must not be anyone inside the passenger compartment when the battery is connected.
- Read off diagnostic trouble codes (DTCs).
The fault is no longer present if the diagnostic trouble code (DTC) status is intermittent.
Is the diagnostic trouble code (DTC) intermittent?
Yes - VERIFIED
No - VERIFICATION FAILED
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VERIFIED - Fault Found
VERIFICATION FAILED - Fault-tracing information
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Fault-tracing information
Information
Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.
Do you want to exit fault-tracing?
Yes - FAULT-TRACING FAILED
No - Attempt New Test
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FAULT-TRACING FAILED - No Fault Found
Attempt New Test - Checking the component
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