4.
Read "DTC Status" parameter.
The Wheel Speed Sensor (WSS) generates a waveform with a frequency proportional to the speed of the vehicle. The signal generated by the WSS informs the ECM not only if the vehicle speed is low or high but also if the vehicle is or is not moving. The ECM uses this signal to control the fuel injection, ignition timing, transaxle shift scheduling and torque converter clutch scheduling. The WSS signal is also used to detect rough road conditions.
The ECM evaluates engine speed and mass air flow if there is no vehicle speed signal. This evaluation of both values will detect open circuit or short circuit errors on the wheel speed sensor. The ECM sets DTC P0501 if there is no vehicle speed signal from wheel speed sensor while both engine speed and mass air flow are higher than predetermined threshold during the predetermined time.
ITEM | DETECTING CONDITION | POSSIBLE CAUSE |
DTC Strategy | ● Check vehicle speed signal | ● Open or short in harness ● Contact resistance in connectors ● Faulty wheel speed sensor |
Enable Conditions | ● Engine speed >2016 rpm ● Mass air flow >218mg/stk ● Coolant temperature > 60℃(140℉) ● No fuel shut-off | |
Threshold Value | ● Vehicle speed = 0 with high engine speed and high load | |
Diagnostic Time | ● 60 sec. (AT)/40 sec. (MT) |
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)".
Press F4(DTAL) to select DTC information from the DTCs menu.
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"?
History (Not Present) fault : DTC occurred but has been cleared.
Present fault : DTC is occurring at present time.
▶ Fault is intermittent, caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM 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.
▶ [With ABS or Except Europe system] Go to "Monitor Scan tool Data" procedure.
[Europe & without ABS system] Go to "Signal Circuit Inspection[Without ABS]" procedure.
With vehicle raised on a lift , start the engine and place transaxle in Drive. Let vehicle idle and verify speedometer indicates approx. 10km/h or more(6mph or more) on the instrument cluster.
[With ABS] Connect Scantool and select ABS system.
[Except Europe] Connect Scantool and select AUTOMATIC TRANSAXLE system.
[With Out]Monitor the "WHEEL SPD SENSOR-FR" parameter on the current data list.
[Except Europe]Monitor the "VEHICLE SPEED" parameter on the current data list.
Specification : 10km/h or more(6mph or more)
Is value within the specification?
▶[With ABS]Wheel speed sensor is OK. Go to Go to "Signal Circuit Inspection[With ABS]" procedure.
[Except Europe]Vehicle speed sensor is OK. Open or short circuit between VSS and ECM control module.
If problems are found, repair as necessary and go to "Verification of Vehicle Repair" procedure.
▶ Check the following conditions:
[With ABS]
Open or short circuit between wheel speed sensor(FR) and ABS(or ESP) control module
If problems are found, repair as necessary and go to "Verification of Vehicle Repair" procedure
If OK, check wheel speed sensor(FR). Repair as necessary and go to "Verification of Vehicle Repair" procedure
[Except Europe]
Open or short circuit between VSS and ECM control module.
If problems are found, repair as necessary and go to "Verification of Vehicle Repair" procedure.
If OK, check VSS. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
[With ABS]
Check for open in circuit
Ignition "OFF".
Disconnect ECM and ABS or ESP Control Module connectors.
Measure resistance between terminals 22 of the ECM harness connector and 3 of the ABS Control Module harness connector(W/ABS).
Measure resistance between terminals 22 of the ECM harness connector and 6 of the ESP Control Module harness connector(W/ESP).
Specification : Approx. 0Ω
Is resistance within the specification?
▶ Go to next step as below
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
Check for short to ground in circuit.
Measure resistance between terminal 22 of the ECM harness connector and chassis ground
Specification : Infinite
Is resistance within the specification?
▶ Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
[Europe & without ABS system]
Check for open in circuit.
Ignition "OFF".
Disconnect ECM and wheel speed sensor(front right) harness connector.
Measure resistance between wheel speed sensor harness connector and ECM harness connector.
Specification : Approx. 0Ω
[W/O 4WD]
Terminal 1(sensor) & Terminal 38(ECM)
Terminal 2(sensor) & Terminal 39(ECM)
[With 4WD]
Terminal 3(sensor) & Terminal 38(ECM)
Terminal 4(sensor) & Terminal 39(ECM)
Is resistance within the specification?
▶ Go to next step as below.
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
Check for short to ground in circuit.
Measure resistance between terminal 38 of the ECM harness connector and chassis ground.
Measure resistance between terminal 39 of the ECM harness connector and chassis ground.
Specification : Infinite
Is resistance within the specification?
▶ Check wheel speed sensor(FR) as follow:
Gap between ABS sensor and trigger wheel (Air gap : 0.3~1.1 mm(0.011 ~ 0.043 in))
Trigger wheel condition
Sensor resistance : Approx. 1,300~1,900Ω at 20℃(68℉)
Replace wheel speed sensor as necessary and go to "Verification of Vehicle Repair" procedure.
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
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.
