Powertrain, generic (extended)

P262D Sensor Reference Voltage G Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P262D says the 5 V reference output G of the engine module is being dragged below its lower limit. Usually something on the line conducts to ground: a chafed wire, water in a plug, or one sensor with an internal short loading the whole group. A useful test is to unplug the sensors on circuit G one by one and watch whether the voltage recovers. No manufacturer documents P262D publicly; for its reference A, Ford's 2012 summary reads under 4.75 V lasting 5 s as a grounded line, and GM's 2019 tables apply a 4.875 V floor to its collective reference codes. The module may limit the output to protect itself, and all sensors on it then report low or invalid signals. P262C is the open or general fault, P262E the high fault of the same circuit.

Likely causes

Reference wire G chafed to ground or engine metal
One sensor on circuit G with internal short pulling the supply down
Water or corrosion in a connector of the group
Weak internal regulator of the engine module

Symptoms

  • Check engine light
  • Several sensors report low or invalid values together
  • Limp mode, reduced power or starting problems possible

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–800
Time1–4 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

P262CP262EP262FP06D7P0642

References: law.cornell.edu, newtonnet.co.uk, gsi.ext.gm.com.