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Throttle Valve Control Module - GX3-, Checking

General Description 

Throttle valve operation occurs by an electric motor identified as the EPC Throttle Drive -G186- located within the Throttle Valve Control Module -GX3-. It is controlled by the Engine Control Module - J623- with primary inputs from the Accelerator Pedal Module -GX2- as well as other peripheral inputs from the EPC Throttle Drive Angle Sensor 1 -G187- and the EPC Throttle Drive Angle Sensor 2 -G188-.

The Throttle Valve Control Module -GX3 / J338- contains the following components:

The Throttle Valve Control Module -GX3 / J338- components cannot be serviced separately, and they 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: -- NO:
  • GATHER more information from customer about the complaint.
  • IGNITION: OFF.
  • 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.
  • IGNITION: OFF.
  • SPECIFIED VALUE: 84 - 97%.
-- Were Values obtained?
-- YES:
  • CONDITION: May be intermittent.
  • PERFORM: Visual Inspection of wiring and component.
  • CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
  • REPAIR: Faulty wiring or connector.
  • GO TO: Step 6 Throttle Valve Control Module - GX3-, CHECKING => 6 .
-- NO:
  • REMOVE: Throttle Valve Control Module -GX3 - far enough so that the harness connector terminals are accessible.
  • DISCONNECT: Throttle Valve Control Module -GX3 - harness connector.
  • IGNITION: ON.
  • CHECK: Throttle Valve Control Module -GX3 - harness connector terminals 2 to 6 for voltage.
  • IGNITION: OFF.
  • SPECIFIED VALUE: About 5.0 V.
-- Was Value obtained?
-- YES: -- NO:
  • REMOVE: Engine Control Module - J623-. Refer to appropriate repair information.
  • CHECK: Throttle Valve Control Module -GX3 - harness connector terminal 1 to the Engine Control Module - J623- harness connector T60 / 41 for resistance.
  • CHECK: Throttle Valve Control Module -GX3 - harness connector terminal 3 to the Engine Control Module - J623- harness connector T60 / 17 for resistance.
  • CHECK: Throttle Valve Control Module -GX3 - harness connector terminal 4 to the Engine Control Module - J623- harness connector T60 / 24 for resistance.
  • CHECK: Throttle Valve Control Module -GX3 - harness connector terminal 5 to the Engine Control Module - J623- harness connector T60 / 16 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES: -- NO:
  • PERFORM: Visual Inspection of wiring and component.
  • CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
  • REPAIR: Faulty wiring or connector.
  • GO TO: Step 6 Throttle Valve Control Module - GX3-, CHECKING => 6 .
  • REMOVE: Engine Control Module - J623-. Refer to appropriate repair information.
  • CHECK: Throttle Valve Control Module -GX3- harness connector terminal 2 to the Engine Control Module - J623- harness connector T60 / 12 for resistance.
  • CHECK: Throttle Valve Control Module -GX3- harness connector terminal 6 to the Engine Control Module - J623- harness connector T60 / 44 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES: -- NO:
  • PERFORM: Visual Inspection of wiring and component.
  • CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
  • REPAIR: Faulty wiring or connector.
  • GO TO: Step 6 Throttle Valve Control Module - GX3-, CHECKING => 6 .
  • Final Procedure 
  • Perform a road test to verify repair.
-- Does the original DTC return?
-- YES:
  • CHECK: Engine Control Module -J623- harness connector for any damaged, pushed-out pins.
  • REPAIR: As necessary.
  • If all electrical connections are OK:
  • REPLACE: Engine Control Module -J623-. Refer to appropriate repair information.
  • Clear the DTC's. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  • Repair is complete. Generate Readiness Code. Refer to READINESS CODE .
  • Return vehicle to Customer.
-- NO:
  • Perform the diagnostic procedure for any DTC's.
  • If no DTC's return, the repair is complete.
  • Return vehicle to customer.