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With Manufacturer's Scan Tool



Throttle Valve Control Module, Checking

- If the throttle valve control module -J338- is removed and installed, or replaced, adaptation of the throttle valve control module to the Motronic ECM is required.

Special tools and equipment
- VAG1551 or VAG1552 Scan Tool (ST) with VAG1551/3 adapter cable
- VAG1598/22 test box
- Multimeter U51119 (Fluke 83 or equivalent)
- VW1594 connector test kit
- Wiring diagrams

Checking requirements
- Throttle valve at idle position
- Accelerator Pedal (AP) cable adjustment OK
- A/C switched off
- Automatic transmission selector lever in "P" or "N" position
- Cruise control system functioning correctly

Function
Idle speed stabilization is integrated in the throttle valve control module -J338-. In the housing opposite the throttle valve are Throttle Position (TP) sensor -G69-, Closed Throttle Position (CTP) switch -F60-, throttle drive -G186- and angle sensor -1- for throttle drive -G187-.

The individual components cannot be replaced or mechanically adjusted. All adjustments are accomplished by the VAG1551 Scan Tool (ST) using the "Basic Setting" function 04.

If the complete throttle valve control module is without power (i.e. disconnected), the throttle valve assumes a mechanical closed throttle position that results in an increased idle speed of 1200-1300 RPM (with engine at operating temperature).

If only the Throttle Position (TP) actuator -V60- is without power, the throttle valve also assumes a mechanical closed throttle position (limp-home position), but because the signal from the CTP switch -F60- can still be recognized, a nearly "normal" idle speed of approx. 900 RPM is maintained with a corresponding reduction of the ignition timing advance.

If the Engine Control Module (ECM) recognizes a malfunction in the angle sensor -1- for throttle drive -G187-, it switches the power off for throttle drive -G186-, and the throttle valve again assumes the mechanical closed throttle position (limp-home position).

Closed Throttle Position (CTP) switch -F60-, checking

- Connect VAG1551 or VAG1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with engine running at idle), refer to "On Board Diagnostic (OBD II)". Testing and Inspection

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press buttons -0-, -0- and -5- to input display group number 5 (005), and press -Q- button to confirm input.

Indicated on display (1-4 = display fields)

Read Measuring Value Block 5 ->
1 2 3 4

- Check Closed Throttle Position (CTP) switch (display field 4):






If displayed values are OK (as specified):
- Press -> button to advance program sequence.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.

Continuation of check when display shows part throttle






- Disconnect 8-pin harness connector -1- for throttle valve control module (arrow -2-).
- Bridge connector terminals 3 and 7 using adapter cables from VW1594 connector test kit and observe display.

When display shows idle:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Replace throttle valve control module, item 16. Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

When display shows part throttle:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Check voltage supply to throttle valve control module and wiring to ECM.

If the voltage supply and wiring is OK:
- Replace Motronic ECM -J220-. Service and Repair

Continuation of check when display constantly shows idle






- Disconnect 8-pin harness connector -1- for throttle valve control module (arrow -2-).

When display shows part throttle:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Replace throttle valve control module, item 16. Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

When display shows idle:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -0- button to confirm input.
- Switch ignition off.
- Check voltage supply to throttle valve control module and wiring to ECM.

If the voltage supply and wiring is OK:
- Replace Motronic ECM -J220-. Service and Repair

Throttle drive -G186- and angle sensor for throttle drive, -G187- checking

Check conditions
- Engine coolant temperature at least 85°C (185°F) See VAG1551 scan tool function 08, display group 004, display field 3. Refer to "On Board Diagnostic (OBD II)". Testing and Inspection

Checking
- Connect VAG1551 or VAG1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with engine running at idle). Refer to "On Board Diagnostic (OBD II)". Testing and Inspection

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press buttons -0-, -5- and -5- to input display group number 55 (055), and press -Q- button to confirm input.

Indicated on display (1-4 display fields)

Read Measuring Value Block 55 ->
1 2 3 4

- Compare display with specified values for idle air control (display fields 1-4):






If displayed values are OK (as specified):
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.

Evaluation of display group 55





Explanation of 4-digit display




NOTE: The increased idle speed (raised RPM) on vehicles with front wheel drive is attained if there is power supplied (B+, 15) to terminal 10 of the ECM.

Continuation






- Disconnect 8-pin harness connector -1- from throttle valve control module (arrow -2-).
- Measure Throttle Position (TP) actuator -V60- resistance between terminals 1 and 2 of throttle valve control module -J338-.
Specified value: 3-200 ohms
- Check voltage supply to throttle valve control module and wiring to ECM

If no malfunction is detected:
- Replace throttle valve control module, item 16, Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

Throttle Position (TP) sensor -G69-, checking

Checking conditions
- Engine coolant temperature at least 85°C (185°F) See VAG1551 scan tool function 08, display group 004, display field 3.

Checking
- Connect VAG1551 or VAG1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with ignition switched; engine not running). Testing and Inspection

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press buttons -0-, -0- and -3- to input display group number 3 (003), and press -Q- button to confirm input.

Indicated on display (1-4 = display fields)

Read Measuring Value Block 3 ->
1 2 3 4

- Compare display with specified values for throttle angle, (display field 3):





- Open throttle valve slowly while monitoring degree (°) value in display field 3.
Value must increase uniformly over the entire range.

If displayed values are OK (as specified):
- Press -> button.
- Press buttons -0 and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.

NOTE: The values displayed in display field 3 depend on the calibration of the Throttle Position (TP) sensor and do not correspond with the actual throttle valve opening in degrees.

If the throttle angle value does not increase uniformly:
- Replace throttle valve control module, item 16, refer to "Throttle Valve Control Module, Removing and Installing". Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

If the display constantly shows angle 0° or is above angle 90°:




Continuation of check when display = angle 0°






- Disconnect 8-pin harness connector -1- for throttle valve control module (arrow -2-).
- Bridge connector terminals 5 and 7 using adapter cables from VW1594 connector test kit and observe display.

When display is above angle 90°:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Replace throttle valve control module, item 16. Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

When display is angle 0°:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Check voltage supply to throttle valve control module and wiring to ECM.

If the voltage supply and wiring is OK:
- Replace Motronic ECM -J220-. Service and Repair

Continuation of check when display is above angle 90°






- Disconnect 8-pin harness connector -1- for throttle valve control module (arrow -2-).

When display is angle 0°:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Replace throttle valve control module, item 16. Service and Repair
- Carry out adaptation of throttle valve control module to ECM.

When display is above angle 90°:
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
- Switch ignition off.
- Check voltage supply to throttle valve control module and wiring to ECM.

If the voltage supply and wiring is OK:
- Replace Motronic ECM -J220-. Service and Repair

Voltage supply and wiring to ECM, checking






- Disconnect 8-pin harness connector -1- for throttle valve control module (arrow -2-).
- Connect multimeter US1119 (Fluke 83 or equivalent) between harness connector terminals 4 and 7, using adapter cables from VW1594 connector test kit.
- Switch ignition on and measure voltage.
Specified value: min. 4.5 volts
- Switch ignition off.
- Connect multimeter to measure voltage between harness connector terminals 3 and 7.
- Switch ignition on and measure voltage.
Specified value: min. 9 volts
- Switch ignition off.






- Connect VAG1598/22 test box to ECM harness connector.






- Check wiring for open circuit between ECM/test box and 8-pin harness connector.
- Connector terminal 1 to ECM/test box socket 66
- Connector terminal 2 to ECM/test box socket 59
- Connector terminal 3 to ECM/test box socket 69
- Connector terminal 4 to ECM/test box socket 62
- Connector terminal 5 to ECM/test box socket 75
- Connector terminal 7 to ECM/test box socket 67
- Connector terminal 8 to ECM/test box socket 74
- Specified value: max. 1.5 ohms

- Check wiring of 8-pin connector for short circuit between wires, according to wiring diagram.
- Specified value: Infinity Ohms

If wiring is OK:
- Check ECM voltage supply. Testing and Inspection
- Carry out adaptation of throttle valve control module to ECM.


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