DTC 25: Passenger's (Front) Air Bag Module (Squib) System Fault 2 (Open in the Squib Circuit): Diagnosis

WARNING: This page is about a different car, the 2005 Dodge Stratus and 2005 Chrysler Sebring. However, it is still accessible from the selected car via links, so may be relevant.

Required Special Tools:

MB991502: Scan Tool (MUT-II)
MB991865: Dummy Resistor
MB991866: Resistor Harness
MB991223 (MB991222): Harness Set (Probe)

STEP 1. Check the passenger's air bag module.
1. Disconnect the negative battery terminal.
2. Disconnect the passenger's air bag module connector C-12.
  
  Fig 1: Identifying Passenger Air Bag Module Connector C-12
  Courtesy of DAIMLERCHRYSLER CORPORATION
3. Connect special tool MB991865 to special tool MB991866.
  CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
4. Insert special tool MB991866 into the C-12 harness side connector by backprobing.
5. Connect the negative battery terminal.
6. Erase the DTC memory, and then recheck the DTC.
Q: Is DTC 25 set?

YES : Go to Step 2.

NO: Replace the passenger's air bag module (Refer to AIR BAG MODULES AND CLOCK SPRING ). Then go to Step 3.

Fig 2: Identifying Special Tools
Courtesy of DAIMLERCHRYSLER CORPORATION
STEP 2. Check the harness wires for open circuit between the SRS-ECU connector C-137 (terminal No.5 and 6) and the passenger's air bag module connector C-12 (terminal No.1 and 2).
1. Disconnect the SRS-ECU connector C-137 and the passenger's air bag module connector C-12.
  
  Fig 3: Identifying SRS-ECU Connector C-137
  Courtesy of DAIMLERCHRYSLER CORPORATION
  
  Fig 4: Identifying Passenger Air Bag Module Connector C-12
  Courtesy of DAIMLERCHRYSLER CORPORATION
  
  CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
2. Check for continuity between the following terminals.
  C-137 connector C-12 connector
  
  6 - 1
  
  5 - 2
  
  It should be less than 2 ohms.
  
  Fig 5: Checking Continuity Between C-12 Connector Terminals
  Courtesy of DAIMLERCHRYSLER CORPORATION
Q: Does continuity exist?

YES : Erase the DTC memory, and recheck if any DTC sets. If DTC 25 sets, replace the SRS-ECU (Refer to SRS CONTROL UNIT (SRS-ECU) ). Then go to Step 3.

NO: Repair the harness wires between the SRS-ECU connector C-137 and the passenger's air bag module connector C-12. Then go to Step 3.
STEP 3. Check the DTC.
Q: Is DTC 25 set?

YES : Return to Step 1.

NO: The procedure is complete (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to TO COPE WITH INTERMITTENT MALFUNCTION ).