DTC P0500: Vehicle Speed Sensor (VSS) A

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DTC P0500: VEHICLE SPEED SENSOR (VSS) A

Description:	Indicates the powertrain control module (PCM) detected an error in the vehicle speed information. Vehicle speed data is received from either the VSS, the transfer case speed sensor (TCSS) or the anti-lock brake system (ABS) control module. If the engine RPM is above the torque converter stall speed (automatic transmission) and the engine load is high, it can be inferred that the vehicle must be moving. If there is insufficient vehicle speed data input, a concern is indicated and this DTC sets. On most vehicle applications the malfunction indicator lamp (MIL) is illuminated when this DTC sets.
Possible Causes:	Open in the VSS+/VSS- harness circuit Open in the TCSS signal or the TCSS signal return harness circuit Short to GND in the VSS harness circuit Short to GND in the TCSS harness circuit Short to voltage in the VSS harness circuit Short to voltage in the TCSS harness circuit Damaged drive mechanism for VSS or TCSS Damaged VSS or TCSS Damaged wheel speed sensors Damaged wheel speed sensor harness circuits Damage in the module(s) connected to the VSC/VSS circuit Open or short in the vehicle speed circuit VSS signal between the ABS VSS signal output and the VSS signal inputs to the PCM and other modules (F-Super Duty)
Diagnostic Aids:	Monitor the VSS PID while driving the vehicle. This DTC sets when the PCM detects a sudden loss of vehicle speed signal over a period of time. If vehicle speed data is lost, check the source of the vehicle speed input: VSS, TCSS or ABS. On some manual shift-on-the-fly (MSOF) applications, VSS and TCSS PID can be monitored. However if no TCSS PID is available and VSS PID is zero, TCSS circuitry frequency must be checked for loss of sensor.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
F-Super Duty	GO to PINPOINT TEST DF .
Expedition, Flex, MKS, MKT, Navigator, Taurus	The powertrain control module (PCM) uses information from the anti lock brake system (ABS) module and the transmission control module (TCM) to calculate vehicle speed. Check these modules for DTCs.
All others	GO to PINPOINT TEST DP .