P0494moderate severityPowertrain
Cooling Fan Speed Low
on 2007 Mercedes-Benz S65 AMG 6.0L V12 BiTurbo M275 · RWD
What this code means
The PCM has detected that the cooling fan speed is lower than expected. Reduced fan speed can cause the engine to overheat under load.
Symptoms
- Engine overheating
- Slow-running cooling fan
- Poor AC cooling
Common causes
- Failing cooling fan motor
- Faulty fan control module
- Poor power or ground connection
- Damaged wiring
Diagnostic steps
- Scan for stored codes
- Monitor actual fan speed data
- Check fan power and ground
- Test fan motor and module
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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