P061C

What it means

P061C is a generic code meaning the engine control module's internal monitoring has found a problem with how engine speed (RPM) is being calculated or processed. The module's independent safety processor compares its own engine speed figure with the main processor's figure, or checks the crank speed signal for plausibility, and the two disagreed beyond the allowed limit. It points to either a faulty speed signal reaching the module or a fault inside the module itself.

Symptoms

• Engine warning light on
• Engine running in limp mode or with reduced power
• Rough running, misfire-like hesitation or surging
• Engine cutting out or difficult to start
• Erratic or incorrect rev counter reading
• Other stored codes for crank or cam sensors

Possible causes

• Faulty or erratic crankshaft position sensor signal, or a damaged reluctor or trigger wheellikely
• Wiring or connector fault on the crankshaft or camshaft sensor circuits (chafing, corrosion, poor pin tension)likely
• Low battery voltage, poor earths or a charging fault causing the module to misread signalspossible
• Camshaft position sensor fault or timing correlation problem, such as a stretched chain or slipped beltpossible
• Outdated or faulty engine control module software where the manufacturer has issued a correctionpossible
• Internal fault in the engine control modulerare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting RPM, load and battery voltage when the code set, and look for crank, cam, misfire or voltage codes that point to the root cause
2. Check battery condition and charging voltage, and inspect the main earths and power feeds to the engine control module
3. Inspect the crankshaft and camshaft sensor wiring and connectors for damage, oil contamination, corrosion and loose pins
4. Compare live engine RPM on a scan tool with the rev counter and check that it is steady at idle and responds smoothly to throttle
5. Inspect the crank and cam sensors and their trigger wheels for damage, debris or excessive air gap, following the procedure for the specific engine
6. Scope the crank and cam signals to check for dropouts, noise or incorrect correlation, and compare with known-good patterns for that model
7. Check the valve timing is correct where the engine design allows it and if signals suggest a correlation problem
8. Check for relevant manufacturer software updates or technical bulletins for the vehicle before condemning the module

How to fix

• Repair or replace damaged wiring and connectors on the crank and cam sensor circuits
• Replace a faulty crankshaft or camshaft position sensor, and correct any damaged or contaminated trigger wheel
• Restore battery, charging and earth faults to bring system voltage and signal quality back within specification
• Correct the engine timing fault and replace worn timing components if correlation is out
• Update the engine control module software where an updated calibration is the known fix
• Repair or replace the engine control module and have it coded or programmed to the vehicle only once all other causes are ruled out

Can I keep driving?

Nearby codes

• P061BGenericInternal Control Module Torque Calculation Performance
• P061DGenericInternal Control Module Engine Air Mass Performance