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 DTC P0638 [L8, LF, L3]

DTC P0638 [L8, LF, L3]

id0102a1809800

DTC P0638

Throttle actuator control circuit range/performance problem

DETECTION CONDITION

• The PCM compares the actual TP with the target TP when the engine is running. If the difference is more than the specification, the PCM determines that there is a throttle actuator control circuit range/performance problem.
Diagnostic support note
• This is a continuous monitor (CCM).
• The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
• PENDING CODE is available if the PCM detects the above malfunction condition.
• FREEZE FRAME DATA is available.
• Are any DTCs is stored in the PCM memory.

POSSIBLE CAUSE

• Throttle actuator malfunction
• Throttle valve malfunction
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY RELATED PENDING CODE OR STORED DTC
• Turn the ignition switch off, then to the ON position (Engine off).
• Verify the related PENDING CODE or stored DTCs.
• Are other DTCs present?
Yes
Go to the applicable DTC inspection.
No
Go to the next step.
4
VERIFY TROUBLESHOOTING OF P0638 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the same DTC present?
Yes
Replace the PCM, go to the next step.
No
Go to the next step.
5
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Is any DTC present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.