Code result
P0542
Intake Air Heater Circuit High
Moderate severity
What it means
Intake Air Heater A Circuit High: the signal voltage is above the expected range. Used on diesel and some petrol engines for cold-start emissions and starting reliability.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Circuit shorted to power
highOne of the most commonly reported causes for this code — check this first.
Ground open
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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