The clearance warning ECU detects obstacles based on signals received from the rear left center sensor. If the rear left center sensor's circuit has an open, short or other malfunction, it will not function normally.

The clearance warning ECU detects obstacles based on signals received from the front left sensor. If the front left sensor's circuit has an open, short or other malfunction, it will not function normally.

When troubleshooting a vehicle with the diagnosis system, the only difference from the usual troubleshooting procedure is connecting the intelligent tester to the vehicle and reading various data output from the vehicle's clearance warning ECU.

The clearance warning ECU records DTCs when the ECU detects a malfunction in the ECU itself or in its circuits.