Service bulletin ITB18-020

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10141447
Published by NHTSA	2018-06-18
Manufacturer's number	ITB18-020
Manufacturer's date	2018-05-24
NHTSA component	ELECTRICAL SYSTEM; EQUIPMENT

NHTSA's summary

2019 QX50; SERVICE INFORMATION FOR DTC P11AB SERVICE INFORMATION The Applied Vehicle has a Diagnostic Trouble Code (DTC) that can be stored if power is interrupted to the Variable Compression Ratio Control Module Circuit under certain conditions. DTC P11AB ? (VCR control module circuit) can be stored if: - 12 volt power is interrupted while the ignition is ON, or up to 3 minutes after the ignition was turned OFF - Refer to the Electronic Service Manual (ESM). Search precautions for removing battery in Title Search for further information. - Vehicle battery has low voltage - Vehicle battery is incorrectly disconnected - Refer to the ESM. Search precautions for removing battery in Title Search for further information. - ECU is disconnected before properly disconnecting the 12 volt battery In these cases DTC P11AB will be accompanied by other DTCs related to low voltage or connection codes. If P11AB is stored during one of the above conditions, with DTCs that are related to low voltage or connection issues, P11AB and related DTCs can be erased with no further action. NOTE: If DTC P11AB is stored by itself, refer to the ESM for further diagnostic information.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system, Equipment and accessories

Trouble codes named

P11AB

Vehicles listed
INFINITI QX50	2019

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
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