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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 Throttle Position Sensor -G69-.

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

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

Special tools and workshop equipment required 

Test Requirements 

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
  • NO:
  • Gather more Information from customer about the complaint
  • 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
  • NO:
  • GO TO: Step
  • 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
  • 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 1 to 2 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
  • NO:
  • GO TO: Step
  • REMOVE: Engine Control Module - J623-. Refer to appropriate service manual.
  • CHECK: Throttle Valve Control Module -J338- electrical connector terminal 3 to the Engine Control Module - J623- electrical connector T105 / 26.
  • CHECK: Throttle Valve Control Module -J338- electrical connector terminal 4 to the Engine Control Module - J623- electrical connector T91 / 84.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω)
-- Was value obtained?
  • YES:
  • REPLACE: Throttle Valve Control Module -J338-. Refer to appropriate repair manual.
  • GO TO: Step
  • 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
  • REMOVE: Engine Control Module - J623-. Refer to appropriate service manual.
  • CHECK: Throttle Valve Control Module -J338- electrical connector terminal 1 to the Engine Control Module - J623- to Ground.
  • CHECK: Throttle Valve Control Module -J338- electrical connector terminal 2 to the Engine Control Module - J623- appropriate fuse. Refer to applicable wiring diagram for fuse positions.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω)
-- Was value obtained?
  • YES: REPLACE Engine Control Module -J623- Refer to appropriate repair manual
  • GO TO: Step
  • 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
  • Final Procedure 
  • Perform a road test to verify repair.
  • Do any DTC's return:
  • NO:
  • Repair is complete, Generate readiness code. Refer to READINESS CODE .
  • Return vehicle to Customer