Throttle Position (TP) Sensor, Checking
Throttle Position (TP) Sensor, Checking
Special Tools and Equipment
- VAG1526A
- VAG1594A
- VAG1598/31
- VAS5051 with VAG5051/1
- or
- VAG1551 with VAG1551/3B
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 VAS5051 tester or VAG1551 scan tool and select the control module for engine electronics using "address word" 01. [1][2]Scan Tool Connecting and Initial Checks
Ignition must remain switched on for this.
When indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- to select "Read Measuring Value Block" and press -Q- button to confirm input.
When indicated on display:
Read Measuring Value Block Q
Input display group number XXX
- Press buttons -0-, -6- and -2- to select "display group number 062" and press -Q- button to confirm input.
Indicated on display:
Read Measuring Value Block 62 ->
1 2 3 4
- Check specified values for E-gas potentiometer voltages in display fields 3 and 4.
Display group 062:
- Observe display field 3 and 4.
- Slowly depress accelerator pedal completely.
Percent indication in display field 3 must rise uniformly. The tolerance range 12 to 97% is not used completely during this.
Percent indication in display field 4 must also rise uniformly. In the process, the tolerance range of 4 to 49% is not completely utilized.
NOTE: 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 of Throttle Position (TP) sensor
- Remove driver-side storage compartment.
- Disconnect harness connector for accelerator pedal position sensor.
- Switch ignition on.
- Connect multimeter for voltage measurement as follows:
If specified values are obtained:
- Also check signal wires.
If specified values are not obtained:
- Check wire connections from Engine Control Module (ECM) to sensors for accelerator pedal position.
Checking wire connections
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Connecting VAG 1598/31 Test Box
- Check the following wire connection for open circuit and short circuit to Ground (GND) and B+:
- Repair open circuit or short circuit if necessary.
If no malfunctions are found in wires:
- Replace accelerator pedal position sensor.
NOTE: For vehicles with automatic transmission, the kick down function must be learned.