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DTC B1432 Side-airbag module (LH) (squib) system (shorted to squib circuit ground)
 
 
cautionIf DTC B1432 is set in SRS-ECU, be sure to diagnose the CAN bus line.
 
 
OPERATION
In case of side collision, when the impact exceeding the threshold is applied to the vehicle, and when the impact is simultaneously detected (turned ON) by the side impact sensor as well as by the analog G-sensor in SRS-ECU, the electric current is supplied from SRS-ECU to the side-airbag module (squib) of impacted side.
 
 
TROUBLE JUDGMENT
The code is set when the input terminal of SRS-ECU side-airbag module (squib) is shorted to ground.
 
 
PROBABLE CAUSES
  • Damaged wiring harness and connectors
  • Side-airbag module (squib) harness shorted to ground
  • Malfunction of SRS-ECU
 
 
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-IIISE), diagnose the CAN bus line.
(1)
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
Connect scan tool (M.U.T.-IIISE). 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.
Is the CAN bus line found to be normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C, Diagnosis ).
 
STEP 2. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
(1) Connect the negative battery terminal.
(2) After erasing the DTC memory, check the DTC again.
(3) Disconnect the negative battery terminal.
Is DTC B1432 set?
Go to Step 3.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
 
STEP 3. Diagnosis check by dummy resistor connection.
(1) Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
(2) Disconnect the side-airbag module (LH) connector, unlock the connector by sliding the locking button to the direction of the arrow as shown in the figure, and then disconnect the connector.
(3) Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991866).
(4)
cautionDo not insert a probe directly into the terminal from the connector front side as the connector contact pressure may be weakened.
Insert the resistor harness probe from the back of side-airbag module (LH) harness side connector.
(5) Connect the negative battery terminal.
(6) After erasing the DTC memory, check the DTC again.
(7) Disconnect the negative battery terminal.
Is DTC B1432 set?
Go to Step 4.
Replace the side-airbag module (LH) (Refer to ).
 
STEP 4. Resistance measurement at the SRS-ECU connector.
(1) Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
(2) Disconnect the SRS-ECU connector.
(3)
dangerDisconnect this side-airbag module connector, and keep the squib circuit shorted.
Disconnect the side-airbag module (LH) connector, unlock the connector by sliding the locking button to the direction of the arrow as shown in the figure, and then disconnect the connector.
(4) Take the measurements below at the SRS-ECU harness side connector.
  • Continuity between SLS-, SLS+ line and body ground
OK: No continuity
Is the check result normal?
Go to Step 5.
Repair the wiring harness SLS-, SLS+ line between the SRS-ECU connector and the side-airbag module (LH) connector.
 
STEP 5. Using scan tool (M.U.T.-IIISE), check whether the DTC is set again.
Is DTC B1432 set?
Replace SRS-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).