Programming and Relearning

Because of its adaptive capability, the Motronic Engine Control Module (ECM) must be returned to its reference settings if:

1. Any of these components have been disconnected while the engine is running:

- Engine Coolant Temperature (ECT) Sensor.
- Mass Air flow Sensor (MAF).
- Throttle Position Sensor (TPS).
- Heated Oxygen Sensor (HO2S).

2. Any of these components have been adjusted or replaced:

- Motronic ECM.
- Mass Air flow Sensor.
- Throttle Position Sensor.
- Throttle body (TB) assembly.

RESETTING REQUIREMENTS
1. Engine oil temperature must be at least 176°F (80°C) and radiator cooling fan has operated at least once.
2. All electrical consumers switched "OFF" (radiator cooling fan must not be running during checking).
3. A/C switched "OFF".
4. Throttle Position Sensor is functioning properly.
5. Idle stabilization system operating properly. The valve must vibrate or hum while the ignition is "ON".
6. The exhaust system must be free of leaks.
7. There can be NO intake manifold vacuum leaks.
8. The Heated Oxygen Sensor must be operating properly.
9. Throttle cable adjustment must be OK.
10. Diagnostic Trouble Code (DTC) memory must be cleared of stored trouble codes. If found, faults must be corrected. DTC memory MUST be erased before starting.

VEHICLE AND EQUIPMENT SET-UP
1. Vehicle in PARK or NEUTRAL with parking brake set.
2. Turn ignition switch "OFF".
3. Connect VW 1367 engine tester using VAG 1367/8 inductive pickup, or a suitable strobe timing light and tachometer may be used.
4. Remove cap from CO Tap Tube. Connect an EPA approved CO tester to the CO Tap Tube using VW special tool #6006-0019 high temperature silicone connecting hose, (or equivalent).

NOTE: Non-approved connecting hoses may dramatically alter your readings. Adaptor must be connected tightly to CO tap tube to prevent measuring errors.

5. Display and erase DTC memory. After display of code 0000 (DTC clear), leave ignition switch turned ON.

ECM BASIC SETTING INITIATING
1. Display and erase DTC memory. After display of code 0000 (DTC clear), leave ignition switch turned ON.
2. START engine and let idle (1300 rpm maximum).

OBD 1 Adaptor:

Jumper Wire To 16-Pin DLC Hookup, Jetta Shown:

3. With engine RUNNING, connect OBD1 adaptor to 16 Pin DLC or if jumper wire is being used join together jumper connectors J1 and J2.

- MIL in dash MUST light up.
- IF NOT:
^ Check wires from DLC to the Motronic ECM for open.
^ Check adaptor/jumper connections.

4. CONTINUE TEST ONLY WHEN:

- Coolant temperature is over 80°C (176°F), or coolant fan has cycled at least once.
- Engine has run 2 minutes or more at Closed Throttle Position.

5. Check closed throttle idle speed. Should be:
- 650rpm to 750rpm (A/C OFF).

6. Check CO content. Should be:
- 0.3 - 1.5 vol. %.

7. Check ignition timing. Should be:
- Approx. 6° BTDC.

NOTE: Coolant Fan MUST NOT BE RUNNING when the following test steps are started. If fan is running, wait for fan cycle to end.

8. Remove OBD1 adaptor from 16 Pin DLC or separate jumper wire connectors J1 and J2 (reverse of step 3).

- MIL will go OFF.

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

9. With engine STILL RUNNING, connect OBD1 adaptor to 16 Pin DLC connector. If using jumper wire, join connectors J1 and J2 together.
10. After approx. 4 seconds, remove OBD1 adaptor from 16 Pin DLC, or separate jumper wire connectors J1 and J2.

- MIL will go OFF, come ON for 2.5 seconds, then go OFF.
- This confirms display signal has been received.
- MIL will then display (flash) trouble code.
- Should be code 0000.

11. Turn ignition switch OFF and remove test equipment.
12. Test drive vehicle for at least 10 minutes (minimum). During test drive, these requirements must be performed:

- Engine coolant temperature must be over 80°C (176°F) for at least 3 minutes.
- At engine speed over 4600 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.
- ECM will not reset properly unless ALL REQUIRED SENSOR SIGNALS have been generated during road test.

Motronic ECM Location:

IF SPECIFIED VALUES ARE NOT OBTAINED:
- With ignition switch OFF, disconnect Motronic Engine Control Module connector and re-connect.
- Test drive car and check DTC memory again.
- Repeat Returning To Basic Settings procedure.