Throttle Position Sensor: Testing and Inspection

Throttle Position (TP) Sensor, Checking

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirement





- The respective fuses of Diesel-Direct fuel injection system must be OK.

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 control module for Diesel-Direct fuel injection system completely independently of each other. Both sensors are installed in one housing.

Test sequence

NOTE: When servicing terminals in the harness connector for the Throttle Position (TP) Sensor, use only gold-plated terminals.

- Remove footwell cover (driver's side).
- Disconnect 6-pin connector from Throttle Position (TP) Sensor.
- Switch ignition on.

Checking voltage supply and wiring to control module





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

If specified values are not obtained:
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test

Vehicles with 80-pin control module





- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 2 + socket 11
Terminal 3 + socket 23
Terminal 4 + socket 24
Terminal 5 + socket 12
Terminal 6 + socket 25 Vehicles with automatic transmission
Terminal 1 + socket 8
Wire resistance: max. 1.5 Ohm

Vehicles with 121-pin control module





- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 2 + socket 12
Terminal 3 + socket 50
Terminal 4 + socket 69
Terminal 5 + socket 70
Terminal 6 + socket 51 Vehicles with automatic transmission
Terminal 1 + socket 63
Wire resistance: max. 1.5 Ohm

Vehicles with 154-pin control module





- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 2 + socket 84
Terminal 3 + socket 39
Terminal 4 + socket 83
Terminal 5 + socket 61
Terminal 6 + socket 17 Vehicles with automatic transmission
Terminal 1 + socket 59
Wire resistance: max. 1.5 Ohm

Continuation for all vehicles
- Also check wires for short circuit to each other, to vehicle Ground (GND) and to B+.
Specified value: Infinite Ohm

If no malfunction is detected in the wiring and if the voltage supply was OK:
- Replace accelerator pedal position sensor, item 4 .
- Erase DTC memory of control module for Diesel- Direct fuel injection system, Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes