DTC 91: Side Impact Sensor (LH) Power Supply Circuit System: 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)
MB991223 (MB991222): Harness Set (Probe)

STEP 1. Check the side impact sensor (LH) power supply circuit at the side impact sensor (LH) connector D-22.
1. Disconnect the side impact sensor (LH) connector D-22, and measure at the wiring harness side.
2. Connect the negative battery terminal.
3. Turn the ignition switch to the "ON" position.
  
  Fig 1: Identifying Connector D-22
  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.
4. Measure the voltage between the D-22 harness side connector terminal 2 and the ground.
  Voltage should be 9 volts or more
Q: Is the measured voltage within the specified range?

YES : Replace the side impact sensor (LH) (Refer to SIDE IMPACT SENSOR ). Then go to Step 3.

NO: Go to Step 2.

Fig 2: Measuring Voltage Between D-22 Harness Side Connector Terminal 2 And Ground
Courtesy of DAIMLERCHRYSLER CORPORATION
STEP 2. Check the harness wires for open circuit or short circuit between the SRS-ECU connector C-145 (terminal No.34 and 36) and the side impact sensor (LH) connector D-22 (terminal No.1 and 2).
Q: Are the harness wires between the SRS-ECU connector C-145 (terminal No.34 and 36) and the side impact sensor (LH) connector D-22 (terminal No.1 and 2) in good condition?

YES : Erase the DTC memory, and recheck if any DTC sets. If DTC 91 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-145 and the side impact sensor (LH) connector D-22. Then go to Step 3.

Fig 3: Identifying Connector C-145
Courtesy of DAIMLERCHRYSLER CORPORATION

Fig 4: Identifying Connector D-22
Courtesy of DAIMLERCHRYSLER CORPORATION
STEP 3. Check for DTC.
Q: Is DTC 91 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 ).