Without Scan Tool

NOTE: Read entire procedure before beginning to ensure all steps and results are understood. Display of trouble codes AND completion of the Diagnostic Test Mode (DTM) MUST BE DONE before erasing stored codes is possible. Follow all steps exactly and complete entire procedure.

DIAGNOSTIC TROUBLE CODES
Diagnostic Trouble Codes (DTC) stored in memory must be manually erased after component malfunction has been detected by Engine Control Module (ECM), following most system troubleshooting procedures or after repair procedures. Failure to clear trouble codes will limit many functions of the Motronic ECM and reduce it's ability to deliver maximum operational performance.

TROUBLE CODE ERASING PROCEDURE
1. Display all stored trouble codes.

- Refer to: HOW TO DISPLAY AND READ DIAGNOSTIC TROUBLE CODES for procedure. Reading Diagnostic Trouble Codes
- If no codes are stored, code 4444 will display and no further action is necessary.

2. Complete component functional checks.

- Refer to: HOW TO DISPLAY AND READ DIAGNOSTIC TROUBLE CODES for procedure. Reading Diagnostic Trouble Codes
- Leave ignition switch ON after completion of DTC.

3. After all codes have displayed and all components have successfully been checked, code 0000 (end of output) will display on the MIL.

- Code 0000 display --- 2.5 second flash (meaning number zero) at 2.5 second intervals.

16-Pin Data Link Connector And Jumper Wire, Jetta Shown:

4. Once display of code 0000 has been achieved, the DTC memory may be cleared by once again connecting the adaptor/jumper connectors for at least 4 seconds then separate.

- The DTC memory is now clear.

5. Test drive vehicle for at least 10 minutes (minimum). During test drive these requirements must be performed:

- Engine coolant temperature must be over 175°F (80°C) for at least 3 minutes.
- At engine speed over 4500 RPM, press accelerator pedal briefly all the way down.
- In 4th gear, starting from approx. 30 mph, accelerate for about 4 seconds with accelerator pedal at half throttle.

6. Activate DTC display once again to ensure no new codes have been generated. If no new codes are present, code 4444 will display to confirm and no further action is needed.

- Refer to: HOW TO DISPLAY AND READ DIAGNOSTIC TROUBLE CODES for procedure. Reading Diagnostic Trouble Codes