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Diagnostic Procedure

DTC B109E:87 DIAGNOSTIC PROCEDURE

Step Inspection Action
1 VERIFY REAR BODY CONTROL MODULE (RBCM) DTCs AGAIN 
Yes Go to the next step.
No Go to Step 8.
2 INSPECT START STOP UNIT CONNECTOR CONDITION 
Yes Go to the next step.
No Repair or replace the connector, then go to Step 7.
3 INSPECT REAR BODY CONTROL MODULE (RBCM) CONNECTOR CONDITION 
  • Disconnect the rear body control module (RBCM) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 7.
4 INSPECT FOR SHORT TO GROUND IN WIRING HARNESS BETWEEN START STOP UNIT AND REAR BODY CONTROL MODULE (RBCM) 
  • Verify that the rear body control module (RBCM) and start stop unit connectors are disconnected.
  • Inspect for continuity between start stop unit terminal 1Q (wiring harness-side) and body ground.
  • Is there continuity?
Yes Refer to the SYSTEM WIRING DIAGRAMS article and verify whether or not there is a common connector between rear body control module (RBCM) terminal 3B and start stop unit terminal 1Q.
If there is a common connector: 
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
  • Repair or replace the malfunctioning part.

If there is no common connector: 
  • Repair or replace the wiring harness which has a short to ground.

Go to Step 7.
No Go to the next step.
5 INSPECT FOR OPEN CIRCUIT IN WIRING HARNESS BETWEEN START STOP UNIT AND REAR BODY CONTROL MODULE (RBCM) 
  • Verify that the rear body control module (RBCM) and start stop unit connectors are disconnected.
  • Inspect for continuity between rear body control module (RBCM) terminal 3B (wiring harness-side) and start stop unit terminal 1Q (wiring harness-side).
  • Is there continuity?
Yes Go to the next step.
No Refer to the SYSTEM WIRING DIAGRAMS article and verify whether or not there is a common connector between rear body control module (RBCM) terminal 3B and start stop unit terminal 1Q.
If there is a common connector: 
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector: 
  • Repair or replace the wiring harness which has an open circuit.

Go to Step 7.
6 PERFORM DTC INSPECTION AND VERIFY START STOP UNIT MALFUNCTION 
Yes Replace the start stop unit, then go to the next step.
(See START STOP UNIT REMOVAL/INSTALLATION .)
No Go to Step 8.
7 VERIFY THAT REPAIRS HAVE BEEN COMPLETED 
Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
8 VERIFY IF OTHER DTCs DISPLAYED 
  • Are any other DTCs displayed?
Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [REAR BODY CONTROL MODULE (RBCM)] .)
No DTC troubleshooting completed.