Diagnostic Test Drive
Diagnostic Test DriveWhen servicing vehicles, the vehicle antilock brake system (ABS) and traction control system (TCS), test drives will be necessary to allow all tests to be run, and all system functions to be enabled and exercised. A test drive may also be required to duplicate specific DTCs covered. The diagnostic system check (including test drive) should be run when vehicle repairs are complete in order to verify the repair.
The diagnostic test drive will vary for ABS/TCS problems.
1. Read the Diagnostic Aids and the Conditions for Setting the DTC.
2. Reconnect any previously disconnected components.
3. Start the engine.
4. Drive the vehicle under the following conditions for at least 10 minutes. At no times should any unlawful or unsafe maneuvers be performed.
^ Highway driving.
^ Rough roads.
^ Verify customers concern and duplicate driving conditions.
^ With the engine still running use the scan tool and check for any DTCs. If any DTCs are set, perform the appropriate DTC table.
Initialization Sequence
The electronic brake control module (ECBM) performs the initialization test once each ignition cycle, when the vehicle speed reaches 15 km/h (9 mph). The initialization sequence cycles each valve solenoid and the pump motor, as well as the necessary relays, to check component operation. If any error is detected, the EBCM will set a DTC. The initialization sequence may be heard and felt while it is taking place, and is considered part of normal operation.