Recall 24V478 covers 162 2023-2025 Thomas Built Buses Saf-T-Liner C2 school buses for silent emergency-exit alarms. Dealer software update is free.
Thomas Built Buses is recalling 162 2023-2025 Saf-T-Liner C2 and Saf-T-Liner C2 Jouley school buses because emergency exit warning alarm sounds fail to activate as required when an emergency hatch or window is open. That can leave the driver without an audible warning, increasing injury risk in a crash, and Thomas Built Buses dealers will complete the free repair.
Does this recall apply to your specific vehicle?
The official, free per-VIN recall check is run by NHTSA. Enter your VIN and we'll forward you directly — and add you to a free watchlist so you hear about new recalls for your vehicle.
Check my VIN at NHTSARecallNotify doesn't check your VIN — NHTSA's official tool does. We use your email only to alert you to new recalls.
Watch this vehicle for recalls
Add it to your free watchlist and we will alert you as new federal recalls are posted for your year, make and model. New-recall alerts are rolling out now.
You are on the watchlist.
We will email you as new federal recalls are posted for your vehicle.
What's wrong?
The emergency exit warning system on 2023-2025 Thomas Built Buses Saf-T-Liner C2 and Saf-T-Liner C2 Jouley school buses is supposed to sound an audible alarm when an emergency hatch or window is open. That alarm helps the driver or staff know that an exit is open when the bus is in a loading, unloading, or emergency-exit condition.
On affected buses, the horn control parameter uses incorrect logic for the audible warning. The setting can silence the alarm after the school bus stop features have been activated and an emergency window or hatch is opened. The hardware is not described as broken in the filing; the problem is the programming that decides when the alarm sounds.
There is no warning sign before failure. An owner, driver, or technician would notice the issue only by testing the emergency hatch or window and confirming that the audible alarm does not sound.
Who's affected?
Includes Saf-T-Liner C2 and Saf-T-Liner C2 Jouley buses across the 2023-2025 model years, all tied to the emergency exit structure component.
| 2025 Thomas Built Buses Saf-T-Liner C2 | body or structural component |
|---|---|
| 2025 Thomas Built Buses Saf-T-Liner C2 Jouley | body or structural component |
| 2024 Thomas Built Buses Saf-T-Liner C2 Jouley | body or structural component |
| 2024 Thomas Built Buses Saf-T-Liner C2 | body or structural component |
| 2023 Thomas Built Buses Saf-T-Liner C2 | body or structural component |
| Units affected | 162 |
| Field incidents | NHTSA has logged no field incidents to date. |
A matching year and model does not guarantee inclusion. Check your VIN to confirm whether your specific bus is included.
What's the safety risk?
If the emergency exit alarm is inaudible, the driver can miss that an exit is open. An open emergency exit increases the risk of injury in a crash. Schedule the software update soon, especially for buses carrying passengers. Repair is free at any franchised Thomas Built Buses dealer.
What should I do?
- Check your VIN to confirm your 2023-2025 Thomas Built Buses Saf-T-Liner C2 or Saf-T-Liner C2 Jouley is included in this recall.
- Contact a franchised Thomas Built Buses dealer to schedule the free emergency sound software update that restores the emergency-exit alarm warning.
- Bring the recall notice if Thomas Built Buses mailed one. If not, reference recall number 24V478 when you call.
- Inspect emergency hatches and windows before passenger service, and take the bus out of service if an exit alarm fails to sound before the repair.
- Call Thomas Built Buses customer service at 1-800-547-0712 with questions about the repair.
What happens at the repair
At the dealer, a Thomas Built Buses technician updates the emergency sound software parameters so the audible warning alarm activates when an emergency hatch or window is open. The software update is free under the recall, with parts and labor covered at an authorized service facility. If you already paid for this software repair, follow the reimbursement instructions in the owner letter and work through an authorized dealer. Bring repair paperwork so the service desk can review the claim under DTNA's reimbursement plan.
| Reimbursement | Reimbursement available |
|---|
Timeline
| June 26, 2024 | NHTSA published the recall |
|---|---|
| July 16, 2024 | Dealer notification began |
| July 16, 2024 | Dealer notification ended |
| August 22, 2024 | Owner notification mailed |
| August 25, 2024 | Interim owner notification (was planned for this date) |
Frequently asked questions
What is recall 24V478?
Recall 24V478 covers 162 Thomas Built Buses school buses with emergency exit alarm software that does not sound when an emergency hatch or window is open. The recall applies to 2023-2025 Saf-T-Liner C2 and 2024-2025 Saf-T-Liner C2 Jouley buses.
What should I do if my 2023-2025 Thomas Built Buses Saf-T-Liner C2 or Saf-T-Liner C2 Jouley is on this recall?
Check your VIN to confirm whether your specific bus is included in recall 24V478. If it is, contact a franchised Thomas Built Buses dealer to schedule the emergency sound software update. Reference recall 24V478 or DTNA recall F1004 when you call.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost, and DTNA says dealers will update the emergency sound software free of charge. Parts and labor are covered at a franchised Thomas Built Buses dealer.
What is the safety risk?
The safety risk is that the driver does not hear an alarm when an emergency hatch or window is open. DTNA says an inaudible alarm that fails to warn the driver of an open emergency exit can increase the risk of injury in a crash.
When were owners notified about recall 24V478?
DTNA mailed owner notification letters on August 22, 2024. If you operate or manage one of these school buses and never received a notice, check your VIN and contact DTNA customer service at 1-800-547-0712 or a franchised Thomas Built Buses dealer.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/24V478000 |
|---|---|
| Thomas Built Buses customer service | 1-800-547-0712 |
| NHTSA recall # | 24V478 |
| NHTSA recall # (full) | 24V478000 |
Source documents
-
Download Quarterly Report (PDF) - Download Owner Notification Letter (PDF)
- Download Owner Notice (PDF)
- Download Recall Report (PDF)
- Download Recall Acknowledgement (PDF)
This article is generated from NHTSA's primary recall filings and reviewed against the source on May 20, 2026. RecallNotify does not paraphrase NHTSA's consequence language; that text is reproduced as written above. Editorial standards →