Signal Too Low

Signal too low

Checking the component




Checking the component

Checking the component








- Ignition off
- Disconnect the battery negative lead
- Disconnect the connector from the inflatable curtain
- Connect special tool 951 1506 Test dummy 951 1506 Test Dummy to the connector for the inflatable curtain
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.

- Ignition on
- Connect the battery negative lead. Wait 10 seconds.

Warning! There must not be anyone inside the passenger compartment when the battery is connected.

Read off diagnostic trouble codes (DTCs).
Try a new inflatable curtain if the diagnostic trouble code (DTC) changes status from a permanent to an intermittent fault.

Other information:
- To access and replace the inflatable curtain for the S40, see IC (inflatable curtain) IC (Inflatable Curtain)
- To access and replace the inflatable curtain for the V40, see IC (inflatable curtain) IC (Inflatable Curtain).









Does the diagnostic trouble code (DTC) status change?

Yes - inter

No - perm

------------------------

perm - Checking components and wiring

inter - Verification

-------------------------------------------------

Checking components and wiring








- Ignition off
- Disconnect special tool 951 1506 Test dummy 951 1506 Test Dummy from the connector for the inflatable curtain.

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.

Check the control module connector visually.
Use an ohmmeter to take a reading between terminals #45 (#20) and #46 (#21).
The ohmmeter should read infinite resistance.
Remedy as necessary.

Other information:
- To access or replace the control module, see SRS control module Removal and Replacement
- To access and replace the inflatable curtain for the S40, see IC (inflatable curtain) IC (Inflatable Curtain)
- To access and replace the inflatable curtain for the V40, see IC (inflatable curtain) IC (Inflatable Curtain)
- To connect the breakout box, see Connecting the breakout box Connecting The Breakout Box
- For information about signals, see Signal specification Signal Description. Supplementary Restraint System (SRS).









Continue - 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 status of the diagnostic trouble code (DTC) has changed to intermittent.





Does the status change?

Yes - VERIFIED

No - VERIFICATION FAILED

------------------------

VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

-------------------------------------------------

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 - Exit fault-tracing

No - Attempt New Test

------------------------

Attempt New Test - Checking the component

-------------------------------------------------