Powertrain, generic · Computer and auxiliary outputs

P06D2 Sensor Reference Voltage E Circuit/Open

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. P06D2 is the general code for circuit E. GM uses it as the collective code for its fifth 5 V reference: petrol engines 2015–2019 flag a reference outside 4.875–5.125 V in 19 of 39 samples with the lamp in the first trip, the 6.6 L Duramax LML/LGH 4.6 V or less for 0.1 s with two trips; GM includes it in its 'engine power limited' group. Which sensors are on circuit E is not listed. GM's hybrid control module uses P06D2 for a separate 12 V reference.

Likely causes

Short in the wire or sensor of a connected sensor
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

P06D3P06D4P06D5P06A3P0697P0641

References: law.cornell.edu, gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.