4.
Monitor the "WHEEL SPEED SENSOR-FR" parameter on the Scantool. (ABS Control or ESP Control)
The wheel speed sensor is the essential component that the PCM uses to calculate vehicle speed. This wheel speed sensor is the active hall-sensor type and good at temperature and noise characteristic. Digital wave is produced as tone wheel rotate according as hall sensor principle. Frequency of duty wave is changed in proportion to rotation of tone wheel and PCM gets vehicle speed through ABS/ESP control unit or the wheel speed sensor(In case of non-ABS/ESP vehicle).
If the vehicle speed signal is below 1.0 Km/h during 2 sec under enable conditions, PCM sets P0501.
Item | Detecting Condition | Possible Cause | |
DTC Strategy | ● Signal check (implausible) | [ABS/ESP Vehicle] ● Poor connection ● Open or short in signal circuit ● ABS/ESP Module ● PCM [Non-ABS/ESP Vehicle] ● Poor connection ● Open or short in power circuit ● Open or short in signal circuit ● WSS | |
Case1 | Enable Conditions | ● Engine speed ＞ 3000rpm ● Engine load ＞ 49.5% ● Coolant temperature＞ - 6℃ ● Gear position : D or R | |
Threshold Value | ● Vehicle speed signal during fuel injection ＜ 1.0 kPh | ||
Case2 | Enable Conditions | ● Engine speed : 1520~3520rpm ● Coolant temperature ＞ - 6℃ | |
Threshold Value | ● Vehicle speed signal during fuel cut-off ＜ 1.0 kPh | ||
Diagnostic Time | ● 2 sec | ||
MIL ON Condition | ● 2 driving cycle | ||
Connect scantool to Data Link Connector(DLC).
Engine start and drive the vehicle on the road.
Monitor the "VSS" parameters on the scantool.(ENG. Control)
Monitor the "WHEEL SPEED SENSOR-FR" parameter on the Scantool. (ABS Control or ESP Control)
Are the parameters displayed correctly? (Compare with the vehicle speed guage.)
▶ Fault is intermittent caused by poor contact in the sensor’s and/or ECM’s connector or wasrepaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poorconnection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of vehicle Repair" procedure.
▶ Check the DTCs on ABS(ESP) Module first. If there are DTCs on ABS(ESP) Module, Refer to the Trouble Shooting Guide for ABS(ESP). But, if there isn't DTC on ABS(ESP) Module, go to "Terminal & Connector Inspection" 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 "Signal Circuit Inspection" procedure.
Check short to ground in harness.
Key "OFF".
Disconnect PCM connector.
Disconnect ABS/ESP control unit connector.
Measure resistance between terminal 20/CGGA-K of PCM harness connector and chassis ground. [A/T]
Measure resistance between terminal 64/CGGM-K of ECM harness connector and chassis ground. [M/T]
Specification : Infinite
Is the measured resistance within specification?
▶ Go to "Check open in harness" as follows.
▶ Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.
Check for open in harness.
Key "OFF".
Disconnect PCM connector.
Disconnect ABS/ESP control unit connector.
Measure resistance between terminal 20/CGGA-K of PCM harness connector and terminal 14/E47(21/E46) of ABS(ESP) control module harness connector.(A/T)
Measure resistance between terminal 64/CGGM-K of ECM harness connector and terminal 14/E47(21/E46) of ABS(ESP) control module harness connector.(M/T)
Specification : Approx. below 1Ω
Is the measured resistance within specifications?
▶ Go to "Component inspection" procedure.
▶ Repair Open circuit and then, go to "Verification of Vehicle Repair" procedure.
ENG "ON".
Measure signal waveform of Vehicle Speed from ABS/ESP Control Module to ECM while driving.
Is the signal waveform normal?
▶ Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage. So, check poor connections and the related circuit between ECM and component thoroughly. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
▶ Substitute with a known - good ABS or ESP control unit and check for proper operation. If the problem is corrected, replace ABS or ESP control unit 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.
