P0483moderate severityPowertrain
Cooling Fan Rationality Check
on 2007 Mercedes-Benz S65 AMG 6.0L V12 BiTurbo M275 · RWD
What this code means
The PCM detected that cooling fan performance does not match expected values. This rationality fault indicates the fan system is not responding correctly to commands.
Symptoms
- Engine overheating
- Fan running at wrong speed
- Warning lamp on
Common causes
- Faulty cooling fan motor
- Damaged wiring or connector
- Faulty fan control module
- Faulty PCM
Diagnostic steps
- Scan for stored codes
- Monitor commanded vs actual fan operation
- Inspect fan wiring and connectors
- Test fan module and PCM signals
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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