P0526moderate severityPowertrain
Cooling Fan Speed Sensor Circuit
on 2007 Mercedes-Benz S65 AMG 6.0L V12 BiTurbo M275 · RWD
What this code means
The PCM detects a problem with the cooling fan speed sensor signal. This sensor tells the module how fast the cooling fan is actually spinning.
Symptoms
- Engine overheating
- Cooling fan runs incorrectly
- Check engine light on
Common causes
- Faulty fan speed sensor
- Damaged wiring or connector
- Failing cooling fan motor
- Faulty PCM
Diagnostic steps
- Scan for stored codes
- Inspect fan sensor wiring
- Check fan speed signal with scan tool
- Test cooling fan operation
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P0004
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P0005
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P0006
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P0007
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P0008
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P0009
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P0010
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