FL904 Alternator Power Cable Connection May Be Loose – 2020-2022 Thomas Built EFX & HDX School Buses

November 2, 2021 NHTSA CAMPAIGN NUMBER: 21V850000

Alternator Power Cable Connection May be Loose

A loose power cable connection may cause electrical arcing, which can increase the risk of a fire.

 

NHTSA Campaign Number: 21V850

Manufacturer Daimler TruckseBay logo North America, LLC

Components ELECTRICAL SYSTEM

Potential Number of Units Affected 1,434

 

Summary

Daimler TruckseBay logo North America, LLC (DTNA) is recalling certain 2020-2022 Thomas Built EFX and HDX school buses. The nut for the power cable stud on the alternator may not have been tightened properly, which can cause a loose cable connection.

 

Remedy

Dealers will inspect the alternator power cable connection and tighten it if necessary, free of charge. Owner notification letters were mailed on December 17, 2021. Owners may contact DTNA customer service at 1-800-547-0712. DTNA’s number for this recall is FL904.

 

Notes

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

 


Thomas Built EFX
Thomas Built EFX

 


Subject: TBB Alternator Cable Loose

Models Affected: Specific model year 2020-2022 Thomas Built Buses EFX and HDX vehicles manufactured October 1, 2019, through August 19, 2021.

 

General Information

Daimler TruckseBay logo North America LLC (DTNA), on behalf of its wholly owned subsidiary, Thomas Built Buses (TBB), has decided that a defect that relates to motor vehicle safety exists on the vehicles mentioned above.

On certain EFX & HDX model school busses, the nut for the power cable stud on the alternator may not have been torqued properly. A loose cable connection on an unfused power cable may increase the risk of a fire.

The alternator power cable connection will be inspected and torqued if necessary. Repairs will be performed by DTNA authorized service facilities.

There are approximately 1,451 vehicles involved.

 

Additional Repairs

Dealers must complete all outstanding Recall and Field Service campaigns prior to the sale or delivery of a vehicle. A Dealer will be liable for any progressive damage that results from its failure to complete campaigns before sale or delivery of a vehicle.

Owners may be liable for any progressive damage that results from failure to complete campaigns within a reasonable time after receiving notification.

Please contact Warranty Campaigns for consideration of additional charges prior to performing the repair.

 

Work Instructions

Please refer to the attached work instructions.

 

Replacement Parts

There are no replacement parts.

 


Chronology :

At the end of July 2021, DTNA received a notification from a dealer of a bus with a loose power cable at the alternator. The dealer reported they inspected four additional units and found the nut that secures the cable to the alternator was not fully torqued. In August, DTNA began an investigation to determine the scope of the issue. At approximately the same time and thru October 2021, DTNA undertook a detailed review of warranty and field reports. Additional instances were identified that may be related to possible loose cable connections at the alternator. In total, 17 instances were identified potentially related to loose positive cable connections at the alternator. There was one occurrence, found in a warranty claim, where the dealer linked the alternator cable connection to a loose cable connection. On October 28, 2021, DTNA with an abundance of caution, decided to conduct a voluntary recall campaign on certain Thomas Built Buses Saf-T-Liner HDX and EFX school buses that may have a loose power cable connections at the alternator. There are no reported injuries or deaths related to this issue.

In February 2022, NHTSA asked for updated information on warranty claims, field service reports, and other things such as the number of deaths and injuries. The response is:

  • In July 2021, DTNA received a dealer notification, described above. Also that month, DTNA received seven claims, within the 17 cited above.
  • In August 2021, DTNA discovered five claims where the alternator cable was loose or detached from the power stud on the alternator, as part of the investigation described above.
  • In September 2021, DTNA received three additional claims, also within the 17 cited above.
  • Subsequent warranty searches revealed other claims, with potentially similar failure modes although the link cannot be verified–one in December 2020 and another in March of 2021.
  • There were no injuries or deaths reported.

 


6 Affected Products

Vehicles

MAKEMODELYEAR
THOMAS BUILT BUSESSAF-T-LINER EFX2020-2022
THOMAS BUILT BUSESSAF-T-LINER HDX2020-2022

 


14 Associated Documents

Manufacturer Notices(to Dealers,etc)

RCMN-21V850-8523.pdf 965.417KB

 


Recall Acknowledgement

RCAK-21V850-7434.pdf 652.216KB

 


Recall 573 Report – Amendment 1

RCLRPT-21V850-3876.PDF 214.029KB

 


Defect Notice 573 Report

RCLRPT-21V850-2839.PDF 214.055KB

 


Miscellaneous Document- Defect Information Report

RMISC-21V850-2812.pdf 727.183KB

 


Miscellaneous Document – Amended DIR

RMISC-21V850-8972.pdf 639.15KB

 


ISSUED Owner Notification Letter(Part 577)

RCONL-21V850-0544.pdf 146.989KB

 


Recall 573 Report – Amendment 2

RCLRPT-21V850-8676.PDF 214.026KB

 


Recall Quarterly Report #1, 2021-4

RCLQRT-21V850-1472.PDF 211.152KB

 


Miscellaneous Document

RMISC-21V850-4098.pdf 703.984KB

 


Recall Quarterly Report #2, 2022-1

RCLQRT-21V850-5454.PDF 211.253KB

 


Recall Quarterly Report #3, 2022-2

RCLQRT-21V850-6204.PDF 211.333KB

 


Recall 573 Report – 2/11/22

RCLRPT-21V850-3115.PDF 214.459KB

 


Recall Quarterly Report #4, 2022-3

RCLQRT-21V850-9845.PDF 211.446KB

 


Latest Recalls Documents

https://www-odi.nhtsa.dot.gov/acms/cs/documentList.xhtml?docId=21V850&docType=RCL

 


 

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Last update on 2026-06-01 / Affiliate links / Images from Amazon Product Advertising API


 

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