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Service bulletin SB-57

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)
TypeService bulletin
NHTSA id10136237
Published by NHTSA2018-05-07
Manufacturer's numberSB-57
Manufacturer's date2018-01-25
NHTSA componentELECTRICAL SYSTEM:12V/24V/48V BATTERY; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ELECTRICAL SYSTEM:SOFTWARE

NHTSA's summary

There is the possibility that the inverter may stop charging the house batteries after one charging sequence even with the motorhome plugged into shore power. This could lead to the house batteries not charging while plugged into shore power. To repair this, the multiplex system program needs to have a programming update installed. Tiffin included parts and instructions needed to update the system by taking to our dealer or a reputable dealer of their choice free of charge to customer.

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, Labels and manuals, 12-volt battery, Software

Vehicles listed
TIFFIN BUS2018
TIFFIN PHAETON2018

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