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Throttle Valve Control Module -J338-, CHECKING: Notes

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 applicable wiring diagram.

Special tools and workshop equipment required 

Test requirements 

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start diagnosis 

-- 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)  
  • Idle stop
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)  
  • Wide Open Throttle (WOT) stop
84.0 to 97.0%

-- Switch ignition off.

If specified values are obtained: 

-- Fault may be intermittent.

-- Check for loose or corroded connections and any leaks in the Intake system.

-- Check Freeze Frame data for conditions when the DTC set.

-- Go to Final procedures

If the specified values are not obtained: 

-- Remove the throttle valve control module far enough so that the electrical connector can be reached.

-- Disconnect the Throttle Valve Control Module -J338- electrical connector.

-- Using a Multimeter, Check the Throttle Valve Control Module -J338- electrical harness connector terminal 1 to 2 to for voltage.

Specified value: Battery Voltage

-- Switch the ignition OFF.

-- Continue test according to the following table:

Value Cause Test
If the specified value was not obtained: Open or shorted circuit Checking wiring 
If the specified value was obtained: Check reference signal circuit Checking wiring