Powertrain, generic · Computer and auxiliary outputs

P061C Internal Control Module Engine RPM Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Electronic throttle systems run a second, independent calculation on the same processor (level 2, at Ford 'IPC – independent plausibility check') that recomputes driver demand, permitted and actual torque and their inputs, and compares them with the main software. P061C means the two internal engine speed calculations from the crankshaft signal disagree. GM's 6.6 L Duramax sets it at 400 rpm or more difference once the redundant speed is at least 600 rpm and the engine is synchronised, after 0.32 s, with the lamp after two trips; Ford's diesel also uses 400 rpm (5 s), Ford petrol engines react within 1 s with the check engine light. Because speed is a base value of torque monitoring, limp mode follows. A disturbed crankshaft signal can make both paths react differently, so fix P0335–P0339 first.

Likely causes

Engine module software or calibration fault (update available)
Disturbed crankshaft signal (sensor, reluctor, shielding, connector, interference)
Voltage dips, poor ground or supply at the module
Internal defect of the engine module

Symptoms

  • Check engine, wrench or service lamp
  • Reduced power or RPM limit
  • Stumbling or brief misfires with a disturbed signal
  • Rarely stalling

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,200
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

engine control modulecrankshaft position sensor

Related codes

P0335P0336P061AP061BP0606P060C

References: law.cornell.edu, gsi.ext.gm.com, fordservicecontent.com, newtonnet.co.uk.