With Generic Scan Tool

Throttle Valve Control Module, Checking

NOTE: Use only gold-plated terminals when servicing terminals in harness connector of throttle valve control module.

Function
The throttle valve activation occurs via an electric motor (throttle drive) in the throttle valve control module. It is activated by the Engine Control Module (ECM) according to specifications of the two sensors, Throttle Position (TP) Sensor -G79- and Sender -2- for accelerator pedal position -G185-, function of the EPC system.

Components of Throttle Valve Control Module -J338-:
- Throttle drive (power accelerator actuation) -G186-
- Angle sensor -1- for throttle drive (power accelerator actuation) -G187-
- Angle sensor -2- for throttle drive (power accelerator actuation) -G188-

Recommended special tools and equipment
- V.A.G1526 multimeter or V.A.G1715 multimeter
- V.A.G1594 connector test kit
- Wiring diagram

Requirements







- The respective fuses of Motronic Engine Control Module (ECM) -J220- must be OK:
- Battery voltage must be at least 11.5 volts.
- All electrical consumers like, lights and rear window heating must be switched off.
- Parking brake must be engaged or else daylight driving lights will be switched on.
- If vehicle is equipped with an A/C system, it must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Throttle valve must not be damaged or dirty.
- Coolant temperature must be at least 80 degrees C, Diagnostic mode 1: Check measuring values; PID 5, Coolant temperature. Diagnostic Mode 1: Check Measured Values

Function test
- Connect diagnostic tester. Diagnostic Tester, Connecting
- Switch ignition on.
- Under address word 33, select "Diagnostic mode 1: Checking measured values."
- Select the measuring value "PID 17: Throttle valve position (absolute)."
- Check specified value of throttle valve position (absolute) at idle stop:







- Slowly depress accelerator pedal up to Wide Open Throttle (WOT) stop while observing the percentage display.
The percentage display must increase uniformly.
- Check specified value of throttle valve position (absolute) at Wide Open Throttle (WOT) stop:







- End diagnosis and switch ignition off.

If specified values are not obtained:

Check resistance
- Connect test box to control module wiring harness. Engine Control Module (ECM) is not connected. Test Box, Connecting For Wiring Test
- Measure resistance of throttle valve drive between test box sockets 117 + 118
Specified value: 1 to 5 Ohms

If specified value is not obtained:
- Replace Throttle Valve Control Module -J338-
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If specified value is obtained:
- Check voltage supply of throttle valve control module and wiring to control module.
- Check Throttle Position (TP) Sensor -G79- and Sender -2- for accelerator pedal position -G185-. Testing and Inspection

If voltage supply and wires are OK:
- Replace Motronic Engine Control Module (ECM) -J220-.

Checking voltage supply and wiring to control module







- Disconnect 6-pin connector -2- at throttle valve control module -1-.
- Connect multimeter to terminals 2 + 6 of connector for voltage measurement.
- Switch ignition on.
Specified value: at least 4.5 V
- Switch ignition off.
- Connect multimeter to terminal 2 of connector and Ground (GND) for voltage measurement.
- Switch ignition on.
Specified value: at least 4.5 V
- Switch ignition off.
- Connect test box to control module wiring harness. Test Box, Connecting For Wiring Test

Engine Control Module (ECM) is not connected.







- Check wires between test box and 6-pin connector for open circuit according to wiring diagram:
Terminal 1 + socket 92
Terminal 2 + socket 83
Terminal 3 + socket 117
Terminal 4 + socket 84
Terminal 5 + socket 118
Terminal 6 + socket 91

Wire resistance: max: 1.5 Ohms

- Check wires for short circuit to each other.
Specified value: Infinite Ohms

If no malfunctions are found in wires:
- Check voltage supply of Engine Control Module (ECM).
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes