Recall 22V438 covers 461 2020-2023 Thomas Built Buses Saf-T-Liner C2 buses for unexpected engine shutdown. Repair is free at franchised Thomas Built Buses dealers.
Thomas Built Buses is recalling 461 2020-2023 Saf-T-Liner C2 school buses with 8.8L LPG engines because the engine control module can set a fault code that shuts the engine down unexpectedly. An unexpected shutdown raises crash risk, and a disabled bus can require evacuation in uncontrolled traffic; Thomas Built Buses dealers will complete the repair free of charge.
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 engine control module, or ECM, on 2020-2023 Thomas Built Buses Saf-T-Liner C2 school buses is the computer that manages engine operation. On buses with the 8.8L LPG engine, it reads sensors and controls the commands that keep the propane-fueled engine running correctly.
On affected buses, the ECM sets a fault code that triggers an unexpected engine shutdown. The filing ties the problem to buses equipped with the PSI 8.8L LPG engine, but it does not give a separate mechanical root cause for why the module sets that code. The practical result is simple: the bus stalls suddenly while it is in use.
There is no warning sign before failure. A driver should not expect a warning light, rough running, or another clear symptom before the engine shuts down.
Who's affected?
Across the 2020, 2021, 2022, and 2023 model years, the listed Saf-T-Liner C2 buses share the same engine control module.
| 2020 Thomas Built Buses Saf-T-Liner C2 | Engine control module (ecu/ecm) |
|---|---|
| 2022 Thomas Built Buses Saf-T-Liner C2 | Engine control module (ecu/ecm) |
| 2021 Thomas Built Buses Saf-T-Liner C2 | Engine control module (ecu/ecm) |
| 2023 Thomas Built Buses Saf-T-Liner C2 | Engine control module (ecu/ecm) |
| Units affected | 461 |
| Field incidents | NHTSA has logged 3 field incidents to date. |
A matching year and model does not guarantee inclusion. Check your VIN to confirm whether this recall applies to your specific bus.
What's the safety risk?
Unexpected engine shutdown can increase crash risk, especially if the bus loses power in traffic. There is no warning sign before shutdown. A disabled school bus also creates passenger risk if evacuation happens in uncontrolled traffic. Schedule the ECM software update soon. Repair is free at any franchised Thomas Built Buses dealer.
What should I do?
- Check your VIN to confirm your 2020-2023 Thomas Built Buses Saf-T-Liner C2 is included in this recall.
- Contact a franchised Thomas Built Buses dealer to schedule the free ECM software update that addresses the fault-code engine shutdown described in the recall.
- Bring the recall notice if Thomas Built Buses mailed one. If not, reference recall number 22V438 when you call.
- Limit bus use until the repair is complete, and brief drivers on engine-shutdown and passenger-evacuation procedures.
What happens at the repair
At the dealer, a Thomas Built Buses technician updates the ECM software so the engine control module uses corrected programming. The software update is free under the recall, and labor is covered at the dealer. Owner notification letters were mailed October 28, 2022, so the service desk can identify the campaign by DTNA recall FL942 if needed. Ask the dealer to confirm the update was completed before the bus returns to service.
Timeline
| June 20, 2022 | NHTSA published the recall |
|---|---|
| August 19, 2022 | Dealer notification began |
| August 19, 2022 | Dealer notification ended |
| August 19, 2022 | Interim owner notification (was planned for this date) |
| October 28, 2022 | Owner notification mailed |
Frequently asked questions
What is recall 22V438?
Recall 22V438 covers 461 2020-2023 Thomas Built Buses Saf-T-Liner C2 school buses with 8.8L LPG engines. The engine control module can set a fault code that causes an unexpected engine shut down. Dealers will update the ECM software for free.
What should I do if my 2020-2023 Thomas Built Buses Saf-T-Liner C2 is on this recall?
Check your VIN to confirm your specific school bus is included in recall 22V438. If it is, contact a franchised Thomas Built Buses dealer to schedule the ECM software update. Reference recall 22V438 or DTNA recall FL942 when you call.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost. For this recall, Thomas Built Buses dealers will update the engine control module software free of charge.
What is the safety risk?
An unexpected engine shut down can increase crash risk. If the school bus becomes disabled in traffic, passengers can face added injury risk during an evacuation in an uncontrolled traffic situation. The repair path is the free ECM software update at a franchised dealer.
When were owners notified about recall 22V438?
Owner notification letters were mailed October 28, 2022. If you bought the bus used or did not receive a letter, check your VIN and call a franchised Thomas Built Buses dealer with recall 22V438 or DTNA recall FL942.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/22V438000 |
|---|---|
| Thomas Built Buses customer service | 1-800-547-0712 |
| NHTSA recall # | 22V438 |
| NHTSA recall # (full) | 22V438000 |
Source documents
-
Download Recall Document (PDF) (PDF) - Download Quarterly Report (PDF)
- Download Owner Notification Letter (PDF)
- Download Misc. Document (PDF)
- Download Recall Report (PDF)
- Download Owner Notice (PDF)
- Download Recall Document (PDF) (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 →