With ABS
DTC P0501 VEHICLE SPEED SENSOR A RANGE/PERFORMANCEABS VEHICLE
Component Location:
GENERAL DESCRIPTION
A Wheel Speed Sensor (RF) is used by the ECM/PCM to calculate vehicle speed. This sensor is connected directly to the ECM/PCM in non-ABS vehicles. On ABS vehicles, the sensor feeds the ABS control module first; the signal is then sent to the ECM/PCM.
DTC DESCRIPTION
If the vehicle speed signal is below 0.62 MPH during 2 sec. under enable condotions, ECM/PCM sets P0501.
DTC Detecting Condition:
Schematic Diagram (A/T):
Schematic Diagram (M/T):
Signal Waveform & Data:
MONITOR SCANTOOL DATA
1. Connect scantool to Data Link Connector (DLC).
2. Warm up the engine to normal operating temperature.
3. Monitor the "VSS" parameters on the scantool. (ENG. Control)
4. Monitor the "WHEEL SPEED SENSOR-FR" parameter on the Scantool. (ABS Control)
5. Are the parameters displayed correctly?
YES - Fault is intermittent caused by poor contact in the sensor's and/or ECM/PCM's connector or was repaired and ECM/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
- If both vehicle speed signal from ECM/PCM and Wheel Speed signal from ABS on current data are not displayed, refer to DTC C1203 "Wheel speed sensor front -RH open/short" in ABS DTC section.
- If the Wheel Speed Signal from ABS is O.K but Vehicle Speed Signal from ECM/PCM on current data is not properly displayed, go to "Inspection and Repair" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminal condition. 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 "Signal Circuit Inspection" procedure.
SIGNAL CIRCUIT INSPECTION
1. Check short to ground in harness.
1. Key "OFF".
2. Disconnect ECM/PCM connector.
3. Disconnect ABS control unit.
PCM A/T:
ECM M/T:
4. Measure resistance between terminal 20/C01-1 of ECM/PCM harness connector and chassis ground.
Measure resistance between terminal 64/C01 of ECM/PCM harness connector and chassis ground.
Specification : Infinite
5. Is the measured resistance within specification?
YES - Go to "Check open in harness".
NO - Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.
2. Check for open in harness.
1. Key "OFF".
2. Disconnect ECM/PCM connector.
3. Disconnect ABS control unit.
PCM A/T:
ECM M/T:
4. Measure resistance between terminal 20/C01-1 of ECM/PCM harness connector and terminal 3/E51 of ABS control module harness connector. (A/T)
Measure resistance between terminal 64/C01 of ECM/PCM harness connector and terminal 3/E51 of ABS control module harness connector. (M/T)
Specification : Approx. below 1 Ohm
5. Is the measured resistance within specifications?
YES - Go to "Component Inspection" procedure.
NO - Repair Open circuit and then, go to "Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
Specification:
1. ENG "ON".
2. Measure signal waveform of Vehicle Speed from ABS to ECM/PCM while driving.
3. Is the signal waveform normal?
YES - Substitute with a known - good ECM/PCM and check for proper operation. If the problem is corrected, replace ECM/PCM and go to "Verification of Vehicle Repair" procedure.
NOTE: There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by ECM/PCM. Before or after testing ECM/PCM on the vehicle, use this function to reuse the ECM/PCM
NO - Substitute with a known - good ABS control unit and check for proper operation. If the problem is corrected, replace ABS control unit and go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
2. Clear the DTCs and Operate the vehicle within DTC Enable conditions in General information.
3. Are any DTCs present?
YES - Go to the applicable troubleshooting procedure.
NO - System is performing to specification at this time.