Powertrain, generic · Computer and auxiliary outputs

P06D8 Sensor Reference Voltage F Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

The engine module feeds sensors from several regulated 5 V reference circuits; a short at one sensor pulls the whole circuit down and all its sensors report at once – unplug them one by one to find the culprit. P06D8 means reference F is too high – a short to voltage, often via a sensor signal wire. No manufacturer document available to us names P06D8 itself; Ram's 6.7 L Cummins documents the neighbouring P06D3. Sensors on the circuit then read too high.

Likely causes

Reference or sensor signal wire shorted to 12 V
Chafing or water in harness or connector
A connected sensor faulty internally
Module internal voltage regulator or components

Symptoms

  • Check engine light
  • Several sensor codes at once
  • Reduced power or limp mode
  • Possibly starting problems

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–600
Time1–3 h

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

Parts involved

sensor reference voltage circuitsensor wiringengine control module

Related codes

P06D6P06D7P06D9P06D4P0193

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