The ECM provides a 5volt reference voltage to Throttle Position Sensor 1(TPS1). The ECM monitors reference voltage deviation from the power supply circuit of the sensors.
Checking the voltage from sensor power supply every 1.87 sec. under detecting condition, if the value within detecting condition lasts for more than 0.2 sec., PCM sets P0641. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Sensor reference voltage check | ● Short in sensor power supply line ● Faulty PCM |
Enable Conditions | ● IG "ON" | |
Threshold value | ● Sensor supply power〈 4.5V or 〉5.5V | |
Diagnosis Time | ● Continuous (More than 0.2 seconds failure for every 1.87 seconds test ) | |
MIL On Condition | ● 2 driving cycle |
Check DTC Status
Connect scantool to Data Link Connector(DLC).
IG "ON".
Select "Diagnostic Trouble Codes(DTCs)" mode, and then Press F4(DTAL) to check DTC's information from the DTCs menu
Read "DTC Status" parameter.
Is parameter displayed "Present fault"?
▶ Go to "Terminal and connector inspection" procedure.
▶ Fault is intermittent caused by poor contact in the sensor’s and/or PCM’s connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
Has a problem been found?
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure
▶ Go to " Power Circuit Inspection " procedure.
Check voltage
IG "OFF".
Disconnect TPS connector.
IG "ON" and ENG "OFF"
Measure the voltage between terminal 4 of TPS harness connector and chassis ground.
Specification : Approx. 5V
Is the measured voltage within specification ?
▶ Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
▶ Go to "Check short in power harness" as follows.
Check short in power harness
IG "OFF".
Disconnect TPS connector and PCM connector.
Measure the resistance between terminal 4 and 5 of TPS harness connector.
Measure the resistance between terminal 4 and 8 of TPS harness connector.
Measure the resistance between terminal 4 and 1 of TPS harness connector.
Measure the resistance between terminal 4 and 6 of TPS harness connector.
Specification : Infinite
Is the measured resistance within specification ?
▶ Substitute with a known - good PCM and check for proper operation.
▶ If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
▶ Repair Short in power circuit and go to "Verification of Vehicle Repair" procedure.
※ Procedure of ETS Initialization
1. Erase the trouble codes on PCM
2. Turn the ignition key off and keep this condition until the main relay is turned off.(It will takes 10 second)
3. Turn ignition key on more than 1second to record the throttle motor position on the EEPROM
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions
Read "DTC Status" parameter
Is parameter displayed "History(Not Present) fault"?
▶ System performing to specification at this time. Clear the DTC.
▶ Go to the applicable troubleshooting procedure.