Powertrain, generic · Fuel and air metering

P017E Cylinder Head Temperature Sensor A Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

The cylinder head temperature sensor A is an NTC thermistor that measures the temperature of the cylinder head metal or of the coolant in the head. Some Ford engines use it instead of a coolant temperature sensor and calculate a coolant value from it; VW group V8 petrol engines use it as sender G407. CARB requires such sensors to be monitored like the coolant sensor. P017E covers intermittent interruptions or an erratic signal. The VW group explicitly uses it for 'open circuit or loose contact', not only for jumps: on Audi and Bentley V8 engines moisture inside sender G407 after O-ring damage makes it fail intermittently, and an improved part has been introduced. Loose contacts and wires broken by heat or engine movement are other causes. The detection logic is not public.

Likely causes

Moisture inside the sensor (O-ring)
Loose contact at connector or pin
Wire broken by engine movement or heat
Sensor faulty internally

Symptoms

  • Check engine light on
  • Intermittent coolant or overheating warning
  • Temperature gauge jumps
  • Radiator fan intermittently loud

Repair estimate

DifficultyMediumDIY possible
Parts and labour€50–600
Time0.5–3 h

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

Parts involved

cylinder head temperature sensorsensor wiringcooling system

Related codes

P017AP017BP017CP017DP0119

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