Diagnostic Trouble Code
P2159
Vehicle Speed Sensor B Range/Performance
Technical Description P2159
Vehicle Speed Sensor "B" Range/Performance
What Does This Mean P2159?
Basically a P2159 trouble code means that the vehicle's speed as read by the Vehicle Speed Sensor (VSS) "B" is outside of the expected range (too high or low for example). The VSS input is used by the vehicle's main computer called a PCM/ECM powertrain/engine control module along with other inputs for proper operation of the vehicle systems.
Typically, the VSS is an electromagnetic sensor that uses a rotating reluctor ring to complete an input circuit to the PCM. The VSS is mounted in the transmission housing at such a position as to allow the reluctor ring to pass by it; in close proximity. The reluctor ring is attached to the output shaft of the transmission so that it spins along with it.
As the reluctor ring passes by the electromagnetic tip of the VSS, notches and grooves serve to complete and interrupt the circuit rapidly. These circuit manipulations are recognized by the PCM as transmission output speed or vehicle speed.
Typically, the VSS is an electromagnetic sensor that uses a rotating reluctor ring to complete an input circuit to the PCM. The VSS is mounted in the transmission housing at such a position as to allow the reluctor ring to pass by it; in close proximity. The reluctor ring is attached to the output shaft of the transmission so that it spins along with it.
As the reluctor ring passes by the electromagnetic tip of the VSS, notches and grooves serve to complete and interrupt the circuit rapidly. These circuit manipulations are recognized by the PCM as transmission output speed or vehicle speed.
Symptoms P2159
1
loss of anti-lock brakes
2
the "anti-lock" or "brake" warning lamps on the dash may be lit
3
the speedometer or odometer may not work properly (or at all)
4
your vehicle's RPM limiter may be decreased
5
the shifting of an automatic transmission may become erratic
6
other symptoms may also be present
Possible Causes P2159
1
The Vehicle Speed Sensor (VSS) "B" is not reading (functioning) properly
2
There is a broken/frayed wire leading to the vehicle speed sensor
3
The vehicle's PCM is not correctly configured for the actual tire size on the vehicle