DTC P0638[ZJ, ZY, Z6]

id0102c1809800


With Throttle Valve Actuator Only

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.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  Throttle actuator malfunction
•  Throttle body 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.
No
Record the FREEZE FRAME DATA on the 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 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.
(See DTC TABLE[ZJ, ZY, Z6].)
No
Go to the next step.
4
INSPECT THROTTLE ACTUATOR
•  Inspect the throttle actuator.
•  Is there any malfunction?
Yes
Replace the throttle body, then go to Step 6.
(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
No
Go to the next step.
5
INSPECT THROTTLE VALVE
•  Inspect the throttle valve.
•  Is there any malfunction?
Yes
Replace the throttle body, then go to the next step.
(See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
No
Go to the next step.
6
VERIFY TROUBLESHOOTING OF P0638 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Start the engine.
•  Is the same DTC present?
Yes
Replace the PCM, go to the next step.
(See PCM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
No
Go to the next step.
7
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[ZJ, ZY, Z6].)
No
DTC troubleshooting completed.