DTC P0638[L3 Turbo]

id0102b7809800

DTC P0638

Throttle actuator control range/performance

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.

•  FREEZE FRAME DATA is available.

•  DTCs are stored in the PCM memory.

POSSIBLE CAUSE

•  Throttle actuator malfunction

•  Throttle valve malfunction

•  PCM malfunction

DTC P0638	Throttle actuator control range/performance
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. • FREEZE FRAME DATA is available. • DTCs are 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 HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record FREEZE FRAME DATA on repair order, then go to the next step.
2	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available?	Yes	Perform the repair or diagnosis according to the available Service Information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT FOR OTHER DTCS • Have other DTCs been stored?	Yes	Perform the diagnostic procedure for the applicable DTCs.
3	INSPECT FOR OTHER DTCS • Have other DTCs been stored?	No	Go to the next step.
4	INSPECT THROTTLE ACTUATOR • Inspect the throttle actuator. (See THROTTLE ACTUATOR INSPECTION[L3 Turbo]) • Is the throttle actuator normal?	Yes	Go to the next step.
4		No	Replace the throttle body, then go to the next step.
5	VERIFY TROUBLESHOOTING OF P0638 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the M-MDS. • Turn the ignition switch off. • Start the engine and let it idle. • Is the same DTC present?	Yes	Replace the PCM, go to the next step. (See PCM REMOVAL/INSTALLATION[L3 Turbo].)
5		No	Go to the next step.
6	VERIFY AFTER REPAIR PROCEDURE • Perform the “After Repair Procedure”. (See AFTER REPAIR PROCEDURE[L3 Turbo].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE[L3 Turbo].)
6		No	Troubleshooting completed.