Powertrain, generic · Computer and auxiliary outputs

P06A3 Sensor Reference Voltage D 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, so all its sensors report at once – unplug them one by one to find the culprit. On GM engines (2016–2025) circuit D feeds pedal sensor 1 and both throttle position sensors, on the Saab 9-4X the throttle and pedal sensor 1 – a fault therefore usually means electronic throttle limp mode. P06A3 is the general code for circuit D. GM's petrol engines (2016–2025) and 2018 diesels use it as the only code for this circuit (4.875–5.125 V, lamp in the first trip); the 2014 6.6 L LML used 4.6 V or less for 1 s with two trips. Saab's 9-3 (2012) also reports it.

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

Symptoms

  • Check engine light
  • Several sensor codes at once (pedal, throttle, pressure)
  • Electronic throttle limp mode, reduced power
  • 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

P06A4P06A5P0697P2122P2135P0641

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