930949

What the Code Means

930949 logs a short to ground in the driver's knee airbag circuit. The ACSM control unit detects a low-resistance path to ground in the circuit, which shouldn't be there on a healthy system.

The usual cause is chafed wiring rubbing against the metal support tubes under the dashboard. Damaged insulation shorts the airbag circuit to the body, and the ACSM puts the restraint system into emergency mode and triggers the fault indicator.

Symptoms

• red airbag indicator on the instrument cluster;
• check control message for the restraint system;
• possible intermittent airbag warning.

Diagnosis and Repair

Fix it using the repair procedure for the chafed knee airbag harness:

1. Remove the center console to access the ACSM.
2. Remove the lower dashboard trim panels.
3. Cut off the damaged harness connectors and insulate the wiring.
4. Install new repair harnesses from the ACSM to both knee airbags (OEM part number not listed in the TSB).
5. Apply felt tape to the edge of the console support to protect the wiring from chafing again.

Replacing only the harness at the damaged section usually doesn't solve the problem for good: without felt tape protecting the support tube, the chafing comes back in the same spot.

Indirect Issues

• chafed wiring eventually becomes a constant short instead of an intermittent one;
• the airbag system may shut down completely or, conversely, deploy unintentionally;
• in a crash, the driver's knee airbag may not deploy, which raises the risk of injury.

This is a restraint-system fault, so don't put off the repair: airbag deployment in a crash depends directly on the condition of the circuit.