Powertrain, generic (extended)

P2148 Fuel Injector Group A Supply Voltage Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2148 flags group A's injector supply as too high. On GM's 2018 Duramax the high-side terminal of injector 1 or 4 shows 0.5 Ω or less to supply potential while the driver is off; same 5-of-10 counting at 100 ms, type A. Ford's 2023 diesels give it a different meaning: the chip that produces the boosted injector voltage inside the module reports an internal fault – a pointer to the control unit rather than the harness. GM's petrol direct injection reads it as excess voltage on the high-side control line of cylinder 1. Bulletins show software and hardware causes: Hino's 2016 J08 trucks set P2148 and P2151 falsely until the ECU is reprogrammed (SB-15-023), and GM PIP6034 replaces the PCM on 2024–25 2.5 L LK0 models. The low fault is P2147.

Likely causes

Injector supply wire shorted to battery voltage
Internal fault of the injector boost circuit in the module
Software falsely detecting the fault, reprogramming available
Injector of the group with internal short

Symptoms

  • Check engine lamp on
  • Misfire and rough running on the affected cylinders
  • Often no drivability complaint when the cause is software

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–2,000
Time0.8–5 h

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

Parts involved

fuel injectorinjector wiringengine control module

Related codes

P2146P2147P2151P0262P062D

References: gsi.ext.gm.com, fordservicecontent.com, static.nhtsa.gov, static.nhtsa.gov.