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Service bulletin 54139

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 id621174
Published by NHTSA2001-09-10
Manufacturer's number54139
Manufacturer's date2001-06-01
NHTSA componentELECTRICAL SYSTEM

NHTSA's summary

SOME VEHICLES MAY EXHIBIT PROBLEMS WITH THE THERMOCOUPLE AND / OR PYROMETER. THIS BULLETIN PROVIDES TROUBLESHOOTING PROCEDURES FOR TESTING ISSPRO THERMOCOUPLES, PYROMETERS, AND RELATED WIRING. *TT

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Electrical system

Vehicles listed
FREIGHTLINER BUSINESS CLASS
FREIGHTLINER FLB
FREIGHTLINER FLD

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