Throttle Valve Control Module, Checking
Throttle Valve Control Module, Checking
NOTE: Use only gold-plated terminals when servicing terminals in the harness connector.
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 Accelerator Pedal Position Sensor 2 -G185-, function of the EPC system.
Components of Throttle Valve Control Module -J338-:
- Throttle drive (power accelerator actuation) -G186-
- Throttle Drive Angle Sensor 1 (for Electronic Power Control (EPC)) -G187-
- Throttle Drive Angle Sensor 2 (for Electronic Power Control (EPC)) -G188-
Recommended special tools and equipment
- V.A.G1526 multimeter or V.A.G1715 multimeter
- V.A.G1594 connector test kit
- Wiring diagram
Test requirements
- Fuses on E-box in engine compartment, left side, must be OK.
NOTE: Fuses on this fuse holder are labelled "SB" in the wiring diagram.
- Fuses on fuse holder in instrument panel, left side, must be OK.
NOTE: Fuses on this fuse holder are labelled "SC" in the wiring diagram.
- Battery voltage must be at least 11.5 Volts.
- All electrical consumers such as, lights and rear window defroster 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; PID 5 ($5), Coolant temperature.
- Ignition switched off.
Function test
Observe safety precautions.
Observe rules for cleanliness.
- Connect diagnostic tester.
- Switch ignition on.
- Under address word 33, select "Diagnostic mode 1: Checking measured values."
- Select measuring value "PID 17 ($11): 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:
- Remove engine cover, removing and disassembling air filter/engine cover.
- Disconnect 6-pin connector from Throttle Valve Control Module -J338-.
Checking resistance
- Check resistance of Throttle Drive (for Electronic Power Control (EPC)) -G186- in Throttle Valve Control Module -J338- between terminals 3 and 5 using adapter cables.
Specified value: 1.0 to 5.0 Ohms
If specified value is not obtained:
- Replace Throttle Valve Control Module -J338-, removing and installing throttle valve control module.
- Erase DTC memory of Engine Control Module (ECM). Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
If specified value is obtained:
- Check voltage supply of throttle valve control module.
- Check wires to Engine Control Module (ECM) according to wiring diagram.
- Check Throttle Position (TP) Sensor -G79- and Sensor 2 for accelerator pedal position -G185-. Testing and Inspection
If voltage supply and wires are OK:
- Replace Engine Control Module (ECM) -J623-.
Checking voltage supply
- Connect multimeter with test leads to terminals 2 and 6 connector for voltage measurement.
- Switch ignition on.
Specified value: at least 4.5 V
- Switch ignition off.
If there is no malfunction in voltage supply:
- Check wires to Engine Control Module (ECM) according to wiring diagram.
Checking wires to Engine Control Module (ECM)
- Connect test box to 60-pin connector of wiring harness. Test Box, Connecting For Wiring Test
Engine Control Module (ECM) is not connected.
- Check wires between test box and 6-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Terminal 1 + socket 12
Terminal 2 + socket 28
Terminal 3 + socket 30
Terminal 4 + socket 27
Terminal 5 + socket 15
Terminal 6 + socket 29
Wire resistance: max. 3.0 Ohms
- Check wires for short circuit to each other, to vehicle Ground (GND) and to B+.
Specified value: Infinity Ohms
- Erase DTC memory of Engine Control Module (ECM). Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
If no malfunctions are found in wires:
- Replace Throttle Valve Control Module -J338-, removing and installing throttle valve control module.
- Erase DTC memory of Engine Control Module (ECM). Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes