Operation CHARM: Car repair manuals for everyone.
Home >> Volkswagen >> 2000 >> Golf (1J1) L4-1.8L Turbo (AWD) >> Repair and Diagnosis >> Sensors and Switches >> Sensors and Switches - Powertrain Management >> Sensors and Switches - Computers and Control Systems >> Throttle Position Sensor >> Testing and Inspection

Throttle Position Sensor: Testing and Inspection




Special tools and equipment







- VAG 1526A multimeter
- VAG 1594A connector test kit
- VAG 1598/31 test box
- VAG 1551 scan tool (or VAG 1552 mobile scan tool) with VAG 1551/3 cable
- Wiring diagram

Function
Both the Throttle Position (TP) sensor - G79 - and the Sender -2- for accelerator pedal position -G185- are located at the accelerator pedal and communicate the driver's intentions to the ECM completely independently of each other. Both sensors are stored in one housing.

Test sequence
- Connect VAG 1551 scan tool (VAG 1552) and select the control module for engine electronics via address word 01. Ignition must be switched on for this.

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q- button to confirm input.

Indicated on display


Read Measuring Valve Block HELP
Input display group number XXX


- Press buttons -0-, -6- and -2- to select "Display group number 62". Press -Q- button to confirm input.

Indicated on display (1-4 = display fields)


Read Measuring Valve Block 62 ->
1 2 3 4


- Check specified value for Throttle Position (TP) sensor -G79- at idle stop in display field 3
Specification: 12-97 %
- Check specified value for sender -2- for accelerator pedal position -G185- at idle stop in display field 4
Specification: 4-49 %


NOTES: Engine Control Module (ECM) calculates the voltage values of the angle sensors in percent relative to 5 volts and displays these percentage values. (5 volts supply voltage represents 100 %).


- Depress gas pedal slowly until Wide Open Throttle (WOT), and observe percent indication in display fields 3 and 4:
Percent indication in display field 3 must climb uniformly. The tolerance range 12 to 97% is not used completely during this.
Percent indication in display field 4 must climb uniformly. In the process, the tolerance range of 4 to 49% is not completely utilized.


NOTES: The indicated value in display field 3 must always be about twice as large as the value in display field 4.


If indications do not resemble description:
- Check voltage supply and wire connections of sensor for accelerator pedal position.

Checking voltage supply and wires to control module

- Remove driver - side storage compartment.
- Disconnect 6-pin harness connector for accelerator pedal position sensor.
- Switch ignition on.







- Connect multimeter to the following connector terminals for voltage measurement.
Terminal 1 + Ground (GND)
Terminal 1 + 5
Terminal 2 + Ground (GND)
Terminal 2 + 3
Specification: at least 4.5 V

- Switch ignition off.

If specified values are not obtained:







- Connect VAG 1598/31 test box to control module wiring harness. Engine Control Module (ECM) is not connected.







- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 1 + socket 72
Terminal 2 + socket 73
Terminal 3 + socket 36
Terminal 4 + socket 35
Terminal 5 + socket 33
Terminal 6 + socket 34
Wire resistance: max. 1.5 ohms

- Also check wires for shorts to Battery B+ or Ground (GND).
- Also check for shorting between wires.

If no malfunctions are found in wires:
- Replace accelerator pedal position sensor See item no.4 in "Electronic Engine Power Control (E - Gas), Checking". Testing and Inspection
In vehicles with automatic transmissions the transmission control module must also be adapted.





pro multis · About Operation CHARM