Recall 21V837 affects 7,322 2020-2023 Ic Bus Cesb school buses for engine shutdown. Repair will be free at a franchised Ic Bus dealer once available.
Ic Bus is recalling 7,322 2020-2023 Cesb school buses because the engine control module can set a fault code that shuts the engine down unexpectedly. An unexpected shutdown increases crash risk and can require an evacuation in uncontrolled traffic; the Ic Bus dealer repair will be free once available.
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What's wrong?
The engine control module, also called the engine ECU, is the computer that manages engine operation on 2020-2023 Ic Bus Cesb school buses. It reads sensors and controls fuel, ignition, and other engine commands so the PSI 8.8L gasoline or second generation LPG engine keeps running as intended.
On affected buses, the ECU software can set a fault code that leads to an unexpected engine shut down. A fault code is the computer's internal error message. Navistar has not finished identifying the root cause, so the exact software or hardware trigger has not been named in the recall filing.
What matters for an owner or fleet is the result: the bus can lose engine power without the driver asking for it. There is no warning sign before failure. If the engine shuts down, the driver has to manage the bus without normal engine power until it is stopped.
Who's affected?
Spans the 2020, 2021, 2022, and 2023 model years, all tied to the same engine control module software.
| 2021 Ic Bus Cesb | Engine control module (ecu/ecm) |
|---|---|
| 2023 Ic Bus Cesb | Engine control module (ecu/ecm) |
| 2022 Ic Bus Cesb | Engine control module (ecu/ecm) |
| 2020 Ic Bus Cesb | Engine control module (ecu/ecm) |
| Units affected | 7,322 |
The year and model narrow the scope, but the VIN decides. Check your VIN to confirm whether your specific bus is included.
What's the safety risk?
Unexpected engine shutdown raises crash risk. On a school bus, a disabled vehicle can force an evacuation in uncontrolled traffic and increase injury risk for passengers. There is no warning sign before shutdown, so keep route staff alert for stalling and report it promptly. Repair will be free at any franchised Ic Bus dealer once available.
What should I do?
- Check your VIN to confirm your 2020-2023 Ic Bus Cesb is included in this recall.
- Contact a franchised Ic Bus dealer to ask when the free ECM reprogramming is open for your bus.
- Reference recall number 21V837 and Ic Bus recall 21507 when you call the dealer.
- Review the Ic Bus owner letter mailed January 18, 2022, for risk guidance before the repair opens.
- Avoid routes or trips where an unexpected engine shutdown would leave the bus in uncontrolled traffic before the ECM is reprogrammed.
What happens at the repair
Once the repair is available, an Ic Bus technician will reprogram the engine control module so it does not set the fault code tied to an unexpected engine shutdown. The dealer repair will be free once it opens, with parts and labor covered under the recall. Navistar has a general reimbursement plan on file. If you already paid for an ECM repair related to this recall, keep your invoices and ask Navistar customer service how to submit documentation.
| Reimbursement | Reimbursement available |
|---|
Timeline
| October 25, 2021 | NHTSA published the recall |
|---|---|
| December 23, 2021 | Dealer notification began |
| December 23, 2021 | Dealer notification ended |
| December 23, 2021 | VIN-searchable in NHTSA's database — Check your VIN to see whether this recall applies to your specific vehicle. |
| December 23, 2021 | Interim owner notification (was planned for this date) |
| January 18, 2022 | Owner notification mailed |
Frequently asked questions
What is recall 21V837?
Recall 21V837 covers 7,322 2020-2023 Ic Bus Cesb school buses with an engine control module fault-code problem that can cause an unexpected engine shutdown. Ic Bus dealers will reprogram the ECM for free once the repair is available.
What should I do if my 2020-2023 Ic Bus Cesb is on this recall?
Check your VIN to confirm your specific school bus is included in recall 21V837. If it is, contact a franchised Ic Bus dealer and reference recall number 21V837. Ask about ECM reprogramming timing and any fleet operating guidance before the repair is complete.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost. For recall 21V837, Ic Bus dealers will reprogram the engine control module free of charge once the repair is available.
What is the safety risk for recall 21V837?
The safety risk is an unexpected engine shutdown. That can increase crash risk, and a disabled school bus can force an evacuation in uncontrolled traffic, increasing injury risk for passengers. Confirm the VIN, then ask the Ic Bus dealer for repair timing and fleet guidance.
When were owners notified about recall 21V837?
Navistar mailed owner letters about the safety risk on January 18, 2022. If your school bus was bought used or transferred between fleets, the letter history is not enough. Check your VIN and call Navistar customer service at 1-800-448-7825 if dealer records need updating.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/21V837000 |
|---|---|
| Ic Bus customer service | 1-800-448-7825 |
| NHTSA recall # | 21V837 |
| NHTSA recall # (full) | 21V837000 |
Source documents
-
Download Recall Document (PDF) (PDF) - Download Quarterly Report (PDF)
- Download Misc. Document (PDF)
- Download Recall Document (PDF) (PDF)
- Download Recall Investigation Document (PDF) (PDF)
- Download Owner Notification Letter (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 →