Throttle Valve Control Module, Checking
Observe all safety precautions: SAFETY PRECAUTIONS .
View clean working conditions: CLEAN WORKING CONDITIONS .
Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.
For wiring diagrams, component locations, and connector views, Refer to the appropriate System Wiring Diagram.
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Engine Control Module - J623- fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched OFF.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N".
- A/C switched OFF.
- Ground (GND) connections between engine/transmission/chassis OK.
- Throttle valve must not be damaged or dirty.
- Coolant Temperature at least 80° C.
Function
Throttle valve operation occurs by an electric motor (Throttle Drive (for Electronic Power Control (EPC)) -G186-) in the Throttle Valve Control Module - J338-. It is operated by the Engine Control Module -J623- and the Accelerator Pedal Position Sensor -G79- /Accelerator Pedal Position Sensor 2 -G185-.
The Throttle Valve Control Module -J338- is made up of the following components:
- Throttle Drive (for Electronic Power Control (EPC)) -G186-
- Throttle Drive Angle Sensor 1 (for Electronic Power Control (EPC)) -G187-
- Throttle Drive Angle Sensor 2 (for Electronic Power Control (EPC)) -G188-
The Throttle Valve Control Module -J338- cannot be serviced separately and must be serviced as a unit.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK
Start diagnosis
-- Remove the engine covers. Refer to the appropriate Service Information.
-- Connect the scan tool.
-- Switch ignition ON.
-- Using the scan tool, check the throttle valve position (absolute) at idle stop:
| Diagnostic text | Specified value |
|---|---|
| Throttle valve position (absolute) | |
|
3.0 to 25.0% |
-- Slowly depress the accelerator pedal to Wide Open Throttle (WOT) stop while observing the percentage display. The percentage display must increase uniformly.
-- Using the scan tool, check the throttle valve position (absolute) at Wide Open Throttle (WOT) stop:
| Diagnostic text | Specified value |
|---|---|
| Throttle valve position (absolute) | |
|
84.0 to 97.0% |
If the specified value was obtained:
-- Switch the ignition OFF.
-- Fault may be intermittent.
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- If necessary, repair the faulty wiring connection.
-- Check Freeze Frame data for conditions when the DTC set.
-- Go to Final procedures.
If the specified value was Not obtained:
-- Remove the Throttle Valve Control Module -J338 - far enough so that the electrical connector terminals are reached.
-- Disconnect the Throttle Valve Control Module -J338- electrical harness connector -1-.
Checking resistance
-- Using a Multimeter, check the Throttle Drive (for Electronic Power Control (EPC)) -G186- at the Throttle Valve Control Module -J338- terminals 5 to 3 for resistance.
Specified value: 1.8 to 5.0 Ω (at 20° C).
If the specified value was Not obtained:
-- Replace the Throttle Valve Control Module - J338-. Refer to appropriate Service Information.
-- Go to Final procedures.
If the specified value was obtained:
-- Check the voltage supply of the Throttle Valve Control Module -J338- to the Engine Control Module -J623-.
Checking voltage supply and wiring
-- Switch the ignition ON.
-- Using a Multimeter, check the Throttle Drive Angle Sensor 1 (for Electronic Power Control (EPC)) -G187- at the Throttle Valve Control Module -J338- electrical harness connector terminals 1 to 6 for voltage.
Specified value: Above 4.5 V
-- Switch the ignition OFF.
If the specified value was obtained:
-- Replace the Throttle Valve Control Module - J338-. Refer to appropriate Service Information.
-- Go to Final procedures.
If the specified value was Not obtained:
Checking wiring
-- Remove the Engine Control Module -J623-. Refer to appropriate Service Information.
-- Using a multimeter, check the Throttle Valve Control Module -J338- at electrical harness connector terminals to the Engine Control Module -J623- electrical harness connector T60 terminals for an open circuit according to the wiring diagram.
| Throttle Valve Control Module -J338- electrical harness connector terminals: | Engine Control Module -J623- electrical connector T60 terminals: |
|---|---|
| 1 | 28 |
| 2 | 14 |
| 3 | 15 |
| 4 | 13 |
| 5 | 30 |
| 6 | 29 |
Specified value: 1.5 Ω max.
If the specified value was Not obtained:
-- Check the wiring for a short circuit to Battery voltage, or an open circuit.
-- If necessary, repair the faulty wiring connection.
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- Go to Final procedures.
If the specified value was obtained:
-- Replace the Engine Control Module -J623-. Refer to appropriate Service Information.
Final procedures
-- Reinstall the engine covers, if necessary. Refer to the appropriate Service Information.
-- After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .