P0651
DTC P0651 SENSOR REFERENCE VOLTAGE "B" CIRCUIT OPENGENERAL DESCRIPTION
ETC(Electronic Throttle Control Valve) is the device controlling amount of air to engine according to driver's intension. Different from the existing mechanical throttle valve which is composed of accelerator pedal and connecting wire cable, ETC consists of a motor, a throttle body and a throttle position sensor. Receiving input signals from electronic accelerator pedal module, PCM lets ETC motor control throttle valve. With ETC, cruise control system works without any additional device.
DTC DESCRIPTION
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 P0651. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition:
Schematic Diagram:
MONITOR SCANTOOL DATA
1. Ignition "OFF"
2. Connect Scantool and Engine "ON"
3. Monitor "TPS1, TPS2" items on Current Data
4. Are those related current data displayed correctly?
YES: Fault is intermittent caused by poor contact in Sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection,bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure
NO: Go to "Terminal and Connector Inspection" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. 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.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO: Go to "Power Circuit Inspection" procedure.
POWER CIRCUIT INSPECTION
1. Check voltage
1. IG "OFF".
2. Disconnect TPS connector.
3. IG "ON" and ENG "OFF"
4. Measure the voltage between terminal 1 of TPS harness connector and chassis ground.
Specification : Approx.5 V
5. Is the measured voltage within specification?
YES: Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "Check short in harness" as follows.
2. Check short in harness
1. IG"OFF".
2. Disconnect TPS connector and PCM connector.
3. Measure the resistance between terminal 1 and 2 of TPS harness connector.
4. Measure the resistance between terminal 1 and 3 of TPS harness connector.
5. Measure the resistance between terminal 1 and 5 of TPS harness connector.
6. Measure the resistance between terminal 1 and 8 of TPS harness connector.
Specification Infinite
7. Is the measured resistance within specification ?
YES: 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.
NO: Repair Short in power harness and go to "Verification of Vehicle Repair" procedure.
- Procedure of ETS Initialization
1. Erase the trouble codes on PCM
2. Turn the ignition key oft and keep this condition until the main relay is turned off.(it will takes 10 seconds)
3. Turn ignition key on more than 1 second to record the throttle motor position on the EEPROM
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions
4. Monitor that all readiness tests have been verified as "Complete"
5. Are any DTC's present?
YES: Go to the applicable trouble shooting procedure.
NO: System is performing to specification at this time.