Throttle Position (TP) Sensor, Checking
NOTE: The Throttle Position (TP) sensor -G69- is located inside the throttle valve control module - J338-.
Test conditions
- Throttle valve in closed throttle position; if necessary adjust accelerator pedal cable
- Cruise control adjustment OK
- Power supply for throttle valve control module OK; checking.
Checking
- Connect VAG 1551 or VAG 1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with ignition switched; engine not running).
Indicated on display
Rapid data transfer HELP
Select function XXX
- 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 Valve Block 3 ->
1 2 3 4
- Compare display with specified values for throttle angle, (display field 3):
Display Group 3:
- Open throttle valve slowly while monitoring degree (°) value in display field 3.
- Value must increase uniformly over the entire range.
- 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. The maximum displayed value is 90.0°.
If the throttle angle value does not increase uniformly:
- Replace throttle valve control module -J338-.
- Carry out adaptation of throttle valve control module to ECM.
- Check readiness code. If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code.
Evaluation of display group 3
Checking wiring
- Connect VAG 1598/22 test box to ECM harness connector.
- Connect multimeter US1119 (Fluke 83 or equivalent), using adapter cables from VW1594 connector test kit.
- Measure resistance to check for short circuit between test box sockets 2 (Ground) and 75 (signal wire).
- Test box sockets 2 and 75
- Specified value: Infinity ohms
- Switch multimeter to voltage (20 VDC) measuring range.
- Switch ignition on.
- Check wiring for short circuit to B+.
- Note voltage reading if applicable (if not 0 volts).
- Switch ignition off.
- Continue test, depending on whether or not voltage was measured.
Continuation (with measured voltage)
- Disconnect 8-pin harness connector from throttle valve control module -J338-.
If measured voltage was approx. 5 volts:
- Connect multimeter US1119 (Fluke 83 or equivalent), using adapter cables from VW1594 connector test kit.
- Measure resistance to check for short circuit between test box sockets 62 (power supply) and 75 (signal wire).
- Test box sockets 62 and 75
- Specified value: Infinity ohms
If measured voltage was approx. battery positive voltage (B+):
- Check wiring at 8-pin connector, terminal 5 for short circuit to battery B+.
Continuation (with no measured voltage)
- Disconnect 8-pin harness connector from throttle valve control module -J338-.
- Check wiring for open circuit between ECM/test box and 8-pin harness connector.
- Connector terminal 5 to ECM/test box socket 75
- Specified value: max. 1.5 ohms
If wiring is OK:
- Replace throttle valve control module -J338-.
- Carry out adaptation of throttle valve control module to ECM.
- Check readiness code. If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code.