Service bulletins for the 2020 GMC Sierra
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
1990 on file from NHTSA, as of 2026-10-19.
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Only bulletins with component: Cooling fan are shown. Show all
| N192266750-02 | 2020-03-23. Service bulletin. FUEL SYSTEM, DIESEL; EQUIPMENT; ENGINE AND ENGINE COOLING:COOLING SYSTEM:FAN; ELECTRICAL SYSTEM. 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 engine fan noise at a low vehicle speed. 3. Under certain conditions, the diagnostic system may set one of the following DTC?s when there is no problem with a component: (P20EE, P226D, P16F3 and P129F). Dealers are to reprogram the engine control module and perform NOx and Catalyst Resets and Regen Enable. |
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The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.