P129F on GMC vehicles

A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.

Owners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.

Bulletins and campaigns GMC filed with NHTSA whose summary names P129F. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• PIE0730 Service bulletin
  2022-12-06 · Electrical System
• This engineering information (EI) is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to the malfunction indicator lamp (MIL) illuminated on driver information center (DIC), vehicle does not start and/or stalls, DTC P129F set.
• PIE0730A Service bulletin
  2022-12-15 · Engine And Engine Cooling
• This engineering information (EI) closure ends the need for gathering information from technicians in regards to the malfunction indicator lamp (MIL) illuminated on driver information center (DIC), vehicle does not start and/or stalls, DTC P129F set.
• PIP5964C Service bulletin
  2024-03-26 · Electrical System
• This Preliminary information communicates a vehicle may come to the dealer with a complaint of no start, stalling, rough idle, no acceleration, loss of power, erratic shifting, fuel gauge inoperative, MIL illuminated with various codes stored. Technicians are directed to replace the K111FPDCM if any of these conditions can be validated and code P023F or P129F is found.
• 24-NA-139 Service bulletin
  2024-07-23 · Fuel/Propulsion System
• This bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Loss of Power, Fuel Gauge Inoperative/Erratic, MIL Illuminated - DTC P023F and/or P129F Set.
• 24-NA-139 Service bulletin
  2024-08-10 · Fuel/Propulsion System
• This bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Loss of Power, Fuel Gauge Inoperative/Erratic, MIL Illuminated - DTC P023F and/or P129F Set.
• 24-NA-139 Service bulletin
  2024-12-11 · Electrical System
• This service bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Malfunction Indicator Lamp (MIL) Illuminated – DTC P023F or P129F Set.
• 24-NA-139 Service bulletin
  2025-04-12 · Engine
• This service bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Malfunction Indicator Lamp (MIL) Illuminated – DTC P023F or P129F Set.
• 24-NA-139 Service bulletin
  2024-08-23 · Fuel/Propulsion System
• This bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Loss of Power, Fuel Gauge Inoperative/Erratic, MIL Illuminated - DTC P023F and/or P129F Set.
• PIP5664B Service bulletin
  2019-09-27 · Electrical System
• This Preliminary information communicates to the dealer technician to check for any new ECM calibration updates for DTCs P129F P16F3 P20EE P20FF P226D P249D P249E P11CC and / or P11D5 set.
• N192266750 Service bulletin
  2019-10-01 · Engine And Engine Cooling
• N192266750 - Service Update. On certain vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1.The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel engine fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2.The customer may compla
• N192266751 Service bulletin
  2019-10-08 · Engine And Engine Cooling
• N192266751 - Service Update (9 VINs moved from N192266750 due to different procedure). On certain vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1.The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel engine fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the prop
• N192266750-02 Service bulletin
  2020-02-14 · Engine And Engine Cooling — Cooling System — Fan
• Service Update - On vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1. The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel exhaust fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2. The customer may complain of excessive e

A stored code names the test that failed, never the part that caused it. The record above is what GMC and its owners have filed about it; the code’s page across every make has the whole file.