P0501

P0501
Vehicle Speed Sensor - Range/Performance Vehicle Speed Sensor (VSS) not in specified range

Function
The system adaptation and the diagnosis for fuel tank ventilation is performed when the vehicle is stationary and the engine is at idle. The diagnosis for misfire recognition is blocked at very high vehicle speed changes. To recognize the vehicle speed, the speed signal for ABS is used.

Diagnostic conditions
A fault is recognized when the engine speed is above 3000 1/min, the load signal is higher than 3.8 ms, the time since last DTC reading is more than 10 sec., and no speed signal was detected.

NOTE: The signal from the right rear wheel speed sensor is used.




Wiring Diagram.

Diagnostic procedure.





Part 1.





Part 2.


Read ABS Control Module fault memory.
1. Connect system tester and switch on.
2. Select vehicle type 911.
3. Select ABS 5 or ABS5/ABD.
4. Read fault memory.

Check speed sensor with ohmmeter.
1. Remove connector X 1/2
2. Connect ohmmeter at sleeve to pin 3 and pin 4.
- Specified value: 1.6 - 1.8 kohm.

Check speed signal with engine tester.
1. Connect engine tester following manufacturer's instructions.
2. Connect cable for special connection (plus) to connector X 1/1 on pin side with pin 4. Connect minus cable to ground.
3. Raise vehicle at right rear
4. Switch ignition on.




5. By hand, turn right rear wheel in driving direction. Display must be as illustrated.