Powertrain, generic (extended)

P2147 Fuel Injector Group A Supply Voltage Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2147 means the common feed of injector group A is pulled toward ground. GM documents it in detail for its 2018 Duramax diesels: the high-side line to injectors 1 and 4 (group 1 on both the 2.8 L four and the 6.6 L V8) shows 0.5 Ω or less to ground while the driver is switched on; with the engine running and more than 11 V, 5 failures in 10 samples at 100 ms set it, type A, lamp on the first trip (2025 tables: 4 of 8). Ford's 2023 diesels report a short of group A to ground or battery found by the driver chip after about 0.2 s. On GM petrol direct injection such as the Saab 9-5 2.0T the code stands for low voltage on the high-side control line of cylinder 1. Both injectors of the group usually stop, so two cylinders drop out. P2148 is the opposite fault.

Likely causes

Injector supply wire chafed and shorted to ground
Injector of the group shorted internally to its body
Water in the injector harness connector
Faulty injector driver in the engine control module

Symptoms

  • Two cylinders misfire at once
  • Heavy loss of power, rough running
  • Check engine lamp on immediately

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,500
Time1–5 h

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

Parts involved

fuel injectorinjector wiringengine control module

Related codes

P2146P2148P2150P0261P062D

References: gsi.ext.gm.com, gsi.ext.gm.com, fordservicecontent.com, saabwisonline.com.