P0851moderate severityPowertrain
Park/Neutral Switch Input Circuit Low
on 2008 Dodge Viper 8.4L V10 · RWD
What this code means
The PCM sees a low voltage input from the park/neutral position switch. This may affect starting and gear-related engine functions.
Symptoms
- No-start in Park or Neutral
- Incorrect gear display
- Backup lights inoperative
Common causes
- Faulty park/neutral switch
- Short to ground in circuit
- Loose or corroded connector
- Failed transmission range sensor
Diagnostic steps
- Retrieve codes and check freeze frame
- Inspect PNP switch wiring for shorts
- Test switch continuity across gear positions
- Replace faulty switch or sensor
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1