DTC B1438: Side impact sensor (front: LH) communication error; DTC B1439: Side impact sensor (front: LH) communication impossible: Diagnosis

WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.

STEP 1. Using scan tool (M.U.T.-III), diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
1. Connect scan tool (M.U.T.-III). Refer to "HOW TO CONNECT THE SCAN TOOL ."
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
1. YES: Go to Step 2.
2. NO: Repair the CAN bus line (Refer to DIAGNOSIS ).
STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is stored.
1. Erase the DTC.
2. Turn the ignition switch to the "ON" position.
3. Check if the DTC is stored.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC stored?
1. YES: Go to Step 3.
2. NO: There is an intermittent malfunction such as poor engaged connector(s) or open circuit (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
STEP 3. Check the side impact sensor (front: LH).
1. Disconnect the negative battery terminal.
2. Alternate the side impact sensor (front: LH) and the side impact sensor (front: RH), and then install the alternated sensor.
3. Connect the negative battery terminal.
4. Erase DTC from memory, and check the DTC.
Q: Is DTC B1438 or B1439 stored?
1. YES: Replace the side impact sensor (front: LH) with a new one (Refer to SIDE IMPACT SENSOR ). Go to Step 5.
2. NO: Go to Step 4.
STEP 4. Check of short to power supply, short to ground, and open circuit in SSL+, SSL- line in between SRS-ECU connector and side impact sensor (front: LH) connector.
Q: Is the check result normal?
1. YES: Go to Step 5.
2. NO: Repair the connectors or harness wires.
STEP 5. Check whether the DTC is stored again.
Check again if the DTC is stored.
1. Erase the DTC.
2. Turn the ignition switch to the "ON" position.
3. Check if the DTC is stored.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC B1438 or B1439 stored?
1. YES: Replace the SRS-ECU (Refer to SRS CONTROL UNIT (SRS-ECU) ).
2. NO: An intermittent malfunction is suspected (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).