Throttle Valve Control Module - J338-, Checking

Function

Throttle valve operation occurs by an electric motor identified as EPC Throttle Drive -G186- located within the Throttle Valve Control Module - J338-. It is controlled by the Engine Control Module - J623- with primary inputs from the Accelerator Pedal Position Sensor -G79- / Accelerator Pedal Position Sensor 2 -G185- as well as other peripheral inputs from EPC Throttle Drive Angle Sensor 1 -G187- and EPC Throttle Drive Angle Sensor 2 -G188-.

The Throttle Valve Control Module -J338- contains the following components:

EPC Throttle Drive -G186-
EPC Throttle Drive Angle Sensor 1 -G187-
EPC Throttle Drive Angle Sensor 2 -G188-

The Throttle Valve Control Module -J338- components cannot be serviced separately, it must be serviced as a unit.

Special Tools And Workshop Equipment Required:

Multimeter
Wiring Diagram
Scan Tool

Test Requirements

Fuses OK.
Battery voltage OK
Switch OFF All electrical and electronic accessories
Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
Vehicles with Manual Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
Coolant Temperature: ≥ 80 °C.
Observe all safety precautions: SAFETY PRECAUTIONS
View clean working conditions: CLEAN WORKING CONDITIONS

Test Procedure

Step	Procedure	Result / Action to Take
1	PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK -- Was complaint verified?	YES: Go to Step 2 in Throttle Valve Control Module - J338-, CHECKING NO: Gather more Information from customer about the complaint
2	CONNECT: Scan Tool. IGNITION: ON CHECK: throttle valve position closed: SPECIFIED VALUE: 3 - 25% DEPRESS: Accelerator pedal slowly to WOT while observing the percentage display. The percentage display must increase uniformly CHECK: throttle valve position at WOT: SPECIFIED VALUE: 84 - 97% IGNITION: OFF -- Was value obtained?	YES: Go to Step 3 in Throttle Valve Control Module - J338-, CHECKING NO: Go to Step 4 in Throttle Valve Control Module - J338-, CHECKING
3	Condition may be intermittent PERFORM: Visual Inspection of wiring and component CHECK: wiring for open, high resistance, short or electrical connector for damage, corrosion, loose or broken terminals REPAIR: faulty wiring or connector	GO TO: Step 7 in Throttle Valve Control Module - J338-, CHECKING
4	REMOVE: Throttle Valve Control Module -J338 - far enough so that the electrical connector terminals are accessible. DISCONNECT: Throttle Valve Control Module -J338- electrical connector IGNITION: ON CHECK: Throttle Valve Control Module -J338- wiring connector pins 2 to 6 for voltage CHECK: Throttle Valve Control Module -J338- wiring connector pin 2 to Ground for voltage SPECIFIED VALUE: About 5.0 V IGNITION: OFF -- Was value obtained?	YES: Go to Step 5 in Throttle Valve Control Module - J338-, CHECKING NO: Go to Step 6 in Throttle Valve Control Module - J338-, CHECKING
5	REMOVE: Engine Control Module - J623-. Refer to appropriate service information. CHECK: Throttle Valve Control Module -J338- electrical connector terminal 1 to the Engine Control Module - J623- electrical connector harness for resistance. From Nov 2009 terminal T60 / 24. From May 2010 terminal T60 / 41 CHECK: Throttle Valve Control Module -J338- electrical connector terminal 4 to the Engine Control Module - J623- electrical connector harness for resistance. From Nov 2009 terminal T60 / 41. From May 2010 terminal T60 / 24 SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω) -- Was value obtained?	YES: REPLACE: Throttle Valve Control Module -J338-. Refer to appropriate Repair Information. GO TO: Step 7 in Throttle Valve Control Module - J338-, CHECKING NO: CHECK: wiring for open, high resistance, short or electrical connector for damage, corrosion, loose or broken terminals REPAIR: faulty wiring or connector GO TO: Step 7 in Throttle Valve Control Module - J338-, CHECKING
6	REMOVE: Engine Control Module - J623-. Refer to appropriate service information. CHECK: Throttle Valve Control Module -J338- electrical connector terminal 2 to the Engine Control Module - J623- electrical connector T60 / 12 resistance. CHECK: Throttle Valve Control Module -J338- electrical connector terminal 3 to the Engine Control Module - J623- electrical connector harness for resistance. From Nov 2009 terminal T60 / 16. From May 2010 terminal T60 / 17 CHECK: Throttle Valve Control Module -J338- electrical connector terminal 5 to the Engine Control Module - J623- electrical connector harness for resistance. From Nov 2009 terminal T60 / 17. From May 2010 terminal T60 / 16 CHECK: Throttle Valve Control Module -J338- electrical connector terminal 6 to the Engine Control Module - J623- electrical connector T60 / 44 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω) -- Was value obtained?	YES: REPLACE Engine Control Module -J623- Refer to appropriate Repair Information GO TO: Step 7 in Throttle Valve Control Module - J338-, CHECKING NO: CHECK: wiring for open, high resistance, short or electrical connector for damage, corrosion, loose or broken terminals REPAIR: faulty wiring or connector GO TO: Step 7 in Throttle Valve Control Module - J338-, CHECKING
7	Final Procedure Perform a road test to verify repair. Do any DTC's return:	YES: Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY . Perform the diagnostic procedure for that DTC. NO: Repair is complete, Generate readiness code. Refer to READINESS CODE . Return vehicle to Customer