P0321high severityPowertrain
Ignition/Distributor Engine Speed Input Circuit Range/Performance
on 2007 Mercedes-Benz S65 AMG 6.0L V12 BiTurbo M275 · RWD
What this code means
The engine speed signal from the ignition or distributor sensor is present but out of expected range. This often means erratic or intermittent RPM readings that confuse the PCM.
Symptoms
- Erratic tachometer readings
- Hard starting or stalling
- Intermittent misfire feel
Common causes
- Faulty crankshaft/RPM sensor
- Damaged sensor wiring or connector
- Reluctor ring damage
- Faulty ignition module
Diagnostic steps
- Scan for related codes and freeze frame
- Inspect sensor wiring and connectors
- Check sensor signal with scope during crank
- Test reluctor ring and sensor air gap
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P0001
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P0002
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P0003
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P0004
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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