[13C] MULTIPORT FUEL INJECTION (MPI) <4G69> - - TROUBLESHOOTING - INSPECTION PROCEDURE FOR DIAGNOSIS CODES - DTC P0638: Throttle Valve Control Servo Circuit Range/Performance Problem | PRINT PAGE / INDEX / PRIOR / NEXT

DTC P0638: Throttle Valve Control Servo Circuit Range/Performance Problem
OPERATION Refer to P2101 - Throttle valve control servo circuit .
FUNCTION Engine-A/T-ECU checks the electronic controlled throttle system for abnormal conditions.
TROUBLE JUDGMENT Check Conditions <Vehicles except for Hong kong> Ignition switch is "ON" position. Accelerator pedal position sensor is normal. Throttle position sensor is normal. Completion of throttle position sensor is learning. Throttle position sensor (main) output voltage is 0.2 - 4.85 V. Battery positive voltage is 8.3 V or higher. Judgement Criteria <Vehicles except for Hong kong> For one second, difference is 1 V or more between voltage in the target opening degree of the engine-A/T-ECU and in the throttle position sensor (main) output. For one second, voltage is 1.5 V or less in the target opening degree controlled by the engine-A/T-ECU. or For one second, difference is 0.6 V or more between voltage in the target opening degree of the engine-A/T-ECU and in the throttle position sensor. Check Conditions Battery positive voltage is 8.3 V or higher. Throttle position sensor (main) output voltage is 0.35 - 4.8 V. <Vehicles for Hong kong> Throttle position sensor (main) output voltage is 0.2 - 4.8 V. <Vehicles except for Hong kong> Ignition switch is "ON" position. Drop of throttle position sensor (main) output voltage per 100 milliseconds is 0.04 V or more. Judgement Criteria Throttle position sensor (main) output voltage has continued to be above 0.5 V higher than the target throttle position sensor (main) voltage for 0.5 second. Check Conditions Battery positive voltage is 8.3 V or higher. Throttle position sensor (main) output voltage is 0.35 - 4.8 V. <Vehicles for Hong kong> Throttle position sensor (main) output voltage is 0.2 - 4.8 V. <Vehicles except for Hong kong> Ignition switch is "ON" position. Judgement Criteria Intelligence power device temperature warning flag set. <Vehicles except for Hong Kong > Difference between throttle position sensor (main) output voltage and target throttle position sensor (main) voltage is 1 V or higher for 4 seconds. Check Conditions <Vehicles except for Hong kong> Ignition switch is "ON" position. Motor relay is ON. Battery positive voltage is 8.3 V or higher. Idle speed control is during the feedback of the engine-A/T-ECU. Completion of throttle position sensor is learning. Water temperature is -40°C or higher. Judgement Criteria <Vehicles except for Hong kong> Throttle position sensor (main) output voltage continued to be above 0.05 V higher than the opening degree of engine-A/T-ECU for 10 seconds. Check Conditions <Vehicles except for Hong kong> Ignition switch is "ON" position. Throttle position sensor is normal. Judgement Criteria <Vehicles except for Hong kong> Throttle position sensor (main) mid opening learning value is 0.4 V or more.
PROBALE CAUSE Failed throttle valve return spring. Failed throttle valve operation. Failed throttle valve control servo. Open/short circuit in throttle valve control servo connector contact. Failed engine-A/T-ECU.
| DIAGNOSIS
| STEP 1. MUT-II/III data list Refer to Data list reference table . Item 9A: Throttle position sensor (main) mid opening learning value Q: Is the check result normal? YES: Go to Step 2 . NO: Replace throttle body assembly.
| STEP 2. Check the throttle valve control servo itself. Check the throttle valve control servo control motor itself (Refer to ) Q: Is the check result normal? YES: Go to Step 3 . NO: Replace electronically controlled throttle valve.
| STEP 3. Connector check: B-33 electronically controlled throttle valve connector and C-138 engine-A/T-ECU connector
| Q: Is the check result normal? YES: Go to Step 4 . NO: Repair.
| STEP 4. Check harness between B-33 (terminal No. 1) electronically controlled throttle valve connector and C-138 (terminal No. 133) engine-A/T-ECU connector.
| Check output line for short circuit and damage. Q: Is the check result normal? YES: Go to Step 5 . NO: Repair.
| STEP 5. Check harness between B-33 (terminal No. 2) electronically controlled throttle valve connector and C-138 (terminal No. 141) engine-A/T-ECU connector.
| Check output line for short circuit and damage. Q: Is the check result normal? YES: Go to Step 6 . NO: Repair.
| STEP 6. Check the trouble symptoms. Q: Does trouble symptom persist? YES: Replace engine-A/T-ECU. NO: Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points ).

[13C] MULTIPORT FUEL INJECTION (MPI) <4G69> - - TROUBLESHOOTING - INSPECTION PROCEDURE FOR DIAGNOSIS CODES - DTC P0638: Throttle Valve Control Servo Circuit Range/Performance Problem | PRINT PAGE / INDEX / PRIOR / NEXT

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