Test DP: Vehicle Speed Sensor: Testing
- 1) DTC P0500: Check VSS PID
DTC P0500 indicates almost zero MPH signal from VSS is sent to PCM even when vehicle is moving. Possible causes are as follows:- Faulty VSS.
- VSS circuit open, or shorted to GND, SIG RTN or VPWR.
- Faulty speedometer.
- Faulty PCM.
Turn ignition off. Raise and support vehicle with drive wheels off ground. Connect scan tool to DLC. Start engine and allow it to idle. Using scan tool, access VSS PID from PID/DATA MONITOR & RECORD menu. With brake pedal applied, place transmission in Drive. Release brakes and observe VSS PID and speedometer reading. If VSS PID reading rises and agrees with speedometer reading, clear DTCs and go to step 10). If speedometer appears to be correct but VSS PID is inaccurate, go to next step. If speedometer reading does not change or does not operate, repair speedometer before continuing diagnosis. See ANALOG INSTRUMENT PANELS - VILLAGER article in ACCESSORIES & EQUIPMENT.
- 2) Check Continuity Of VSS Circuit Between Instrument Cluster & PCM
Turn ignition off. Disconnect PCM harness connector. Disconnect instrument cluster 12-pin connector C266a (analog) or 16-pin connector C267a (electronic). Using DVOM, measure resistance of VSS circuit (Green/Yellow wire) between PCM harness connector terminal No. 27 and instrument cluster harness connector C266a terminal No. 12 (analog), or C267a terminal No. 6 (electronic). See Figure and Figure, or Figure . If resistance is less than 100 ohms, go to next step. If resistance is 100 ohms or more, repair open in VSS circuit. See WIRING DIAGRAMS article. Reconnect all electrical connections and go to step 10). - 3) Check VSS Circuits For Short To GND, SIG RTN Or VPWR
Leave PCM and instrument cluster harness connectors disconnected. Using DVOM, measure resistance between VSS circuit terminal No. 27 and GND, SIG RTN and VPWR circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION table. See Figure. If all resistances are more than 10 k/ohms, check speedometer operation. If speedometer is not operating properly, repair speedometer before continuing diagnosis. See ANALOG INSTRUMENT PANELS - VILLAGER article in ACCESSORIES & EQUIPMENT. If speedometer operation is okay, go to next step. If any resistance is 10 k/ohms or less, repair short between circuits and then go to step 10). - 4) Check Continuity Of VSS Circuit Between Instrument Cluster & VSS
Disconnect VSS connector. On models with analog instrument cluster, disconnect instrument cluster 22-pin connector C266b. On all models, measure resistance of VSS circuit (Pink/Blue wire) between VSS harness connector terminal No. 1 and instrument cluster harness connector C266b terminal No. 22 (analog), or C267a terminal No. 3 (electronic). See Figure and Figure, or Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in VSS circuit. See WIRING DIAGRAMS article. - 5) Check For Short To Ground In VSS Circuit Between VSS & Instrument Cluster
Using DVOM, measure resistance between chassis ground and VSS circuit at instrument cluster harness connector C266b terminal No. 22 (analog), or C267a terminal No. 3 (electronic). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in VSS circuit. See WIRING DIAGRAMS article. - 6) Check VSS Output
Remove VSS from transaxle. Connect DVOM, set on AC Voltage scale, to VSS terminals. Using DVOM, measure AC voltage while quickly turning VSS pinion gear. If voltage reading is about .5 volt, replace PCM. If voltage reading is not about .5 volt, replace VSS.NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 6) to step 10). No test procedures have been omitted. - 10) VSS Drive Cycle Test
Start engine and warm to normal operating temperature. Perform the following drive cycle test 3 times:Drive Cycle Test
- Place transmission in Drive.
- Obey all traffic laws and accelerate quickly to 35 MPH.
- Coast down to an idle and stop vehicle.
- Turn ignition off.
After drive cycle is complete, perform QUICK TEST and retrieve DTCs. Service any DTCs present. Go to DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are present, VSS circuit is okay and testing is complete.