Powertrain, generic (extended)

P2CE2 Intake Air Heater C Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2CE2 is the plausibility test for intake air heater C: the circuit is neither open nor shorted, but current draw, voltage drop or heating effect do not fit the command. Under the heavy-duty OBD rules a glow plug or intake air heater must react properly to commands and its circuit must show plausible current and voltage drop. No manufacturer documents P2CE2 publicly. Volvo and Mack, the only makers seen using heater C codes, list for their pre-heat relay issue the Range/Performance codes of heaters A and B (P2604-7F, P2606-7F) together with the open, low and high codes of heater C, but no C plausibility code. Their repair path still fits: terminal tension, EMS software level, then relay and supply cable. Expect sluggish cold starts and white smoke.

Likely causes

Extra resistance from corroded terminals or a worn supply cable lowering heater current
Pre-heat relay switching with excessive voltage drop
Heating element C aged, drawing current outside the expected window
Weak batteries or poor main ground distorting the current and voltage reading

Symptoms

  • Longer cranking on cold mornings
  • White smoke and rough running until warm
  • Warning lamp without an open or short code for heater C

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–900
Time0.5–3 h

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

Parts involved

intake air heater cheater relaywiring harnessecm

Related codes

P2CE1P2CE3P2CE4P2604P2606P2609

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov.