Inspection Procedure

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Check wire harness .
PREPARATION: Disconnect the connector of tuner and body ECU.

CHECK: the continuity between wire harness and body ground.

OK: No continuity.

Fig 1: Testing Body ECU To Tuner Wire Harness For Short To Ground
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1. NG: Repair or replace the wire harness.
2. OK: Go to 2.
Check body ECU.
PREPARATION: Connect the connector of body ECU.

Fig 2: Connecting Body ECU To Wire Harness
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CHECK: the DTC.

OK: B1242/42 is not output.
1. NG: Replace the body ECU.
2. OK: Replace the tuner.