Powertrain, generic · Computer and auxiliary outputs

P06A5 Sensor Reference Voltage D 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, 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. P06A5 means reference D is too high – a short to voltage, for example via a sensor signal wire. No manufacturer document available to us uses P06A5 itself: GM and Saab report circuit D faults collectively as P06A3. The description follows circuits A–C.

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

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

P06A3P06A4P0699P0643P2123

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