P0504moderate severityPowertrain
Brake Switch A/B Correlation
on 2005 Dodge Viper 8.3L V10 · RWD
What this code means
The two brake light switch signals disagree with each other. The PCM can't confirm whether the brake pedal is truly pressed.
Symptoms
- Check engine light on
- Cruise control won't engage
- Erratic brake lights
Common causes
- Faulty brake light switch
- Misadjusted brake switch
- Wiring fault between switches
- Poor connector contact
Diagnostic steps
- Scan for brake switch data
- Check brake switch adjustment
- Compare both switch signals on scan tool
- Inspect brake switch wiring and connectors
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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