Recall 20V783 covers 7 2020-2021 Aev ambulances with Vista IV LCD displays that can lock up. Replacement units are free at any franchised Freightliner dealer.
Aev is recalling 7 2020-2021 Type 1 F-Series Ambulance, Traumahawk, and Freightliner M2 Ambulance vehicles under recall 20V783 because the Weldon V-Mux Vista IV Standard LCD display can lock up or stop working. The display controls emergency lighting and HVAC functions, and a failure can delay emergency efforts; Freightliner dealers will complete the free repair.
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What's wrong?
The Weldon V-MUX IV Interface in these 2020-2021 Aev ambulances is the LCD control display for emergency lighting and HVAC functions. It gives the operator a central screen to manage equipment that the ambulance body depends on during service. The display is designed to run between 9 and 32 volts DC.
The problem starts when voltage at the display drops below its operating range, including during engine start. A normal display shuts off, then restarts automatically once power returns. On affected Type 1 F-Series Ambulance, Traumahawk, and Freightliner M2 Ambulance vehicles, the display does not restart on its own after a low-voltage dip. The screen locks up or becomes nonfunctional, leaving the lighting and HVAC controls unavailable from that interface.
There is no warning sign before failure. The first sign is the display locking up or going nonfunctional after a voltage drop.
Who's affected?
Covers three ambulance models across the 2020 and 2021 model years, with the same Weldon V-MUX IV interface.
| 2020 Aev Type 1 F-Series Ambulance | instrument panel |
|---|---|
| 2020 Aev Traumahawk | instrument panel |
| 2021 Aev Traumahawk | instrument panel |
| 2021 Aev Freightliner M2 Ambulance | instrument panel |
| Units affected | 7 |
| Field incidents | NHTSA has logged no field incidents to date. |
A matching year and ambulance model does not guarantee inclusion. Check your VIN to confirm whether your specific vehicle is included.
What's the safety risk?
A locked or non-functional LCD display delays emergency efforts and increases the risk of injury. If the display stops responding, document the failure and arrange recall service soon so the dealer installs the replacement Vista IV unit. Repair is free at any franchised Freightliner dealer.
What should I do?
- Check your VIN to confirm your 2020-2021 Aev Type 1 F-Series Ambulance, Traumahawk, or Freightliner M2 Ambulance is included in this recall.
- Contact a franchised Freightliner dealer to schedule the free Vista IV display replacement that fixes the lighting and HVAC display lockup.
- Call Aev customer service at 1-800-447-0343 with questions and reference recall number 20V783 (Halcore recall 20E-078) when you call.
- Bring the recall notice if Aev or Halcore has mailed one. If not, give the dealer recall number 20V783.
- Keep emergency lighting and HVAC controls checked before use until the replacement display is installed.
What happens at the repair
At the dealer, a Freightliner technician provides an updated replacement Vista IV display unit for the affected emergency vehicle lighting and HVAC control display. The replacement unit and labor are free under recall 20V783. Halcore has a general reimbursement plan on file for owners who already paid for the same Vista IV display repair before the recall repair was performed. If you have prior repair paperwork, bring invoices and payment documentation to the service desk and ask how to submit the claim under Halcore's reimbursement plan.
| Reimbursement | Reimbursement available |
|---|
Timeline
| December 15, 2020 | NHTSA published the recall |
|---|---|
| December 21, 2020 | Dealer notification began |
| December 21, 2020 | Interim owner notification (was planned for this date) |
| January 11, 2021 | Owner notification mailed |
| January 15, 2021 | Dealer notification ended |
Frequently asked questions
What is recall 20V783?
Recall 20V783 covers 7 2020-2021 Aev Type 1 F-Series Ambulance, Traumahawk, and Freightliner M2 Ambulance vehicles with Weldon V-Mux Vista IV LCD displays. Low-voltage spikes can lock up the display or make it stop working, affecting emergency lighting and HVAC controls. Halcore's repair replaces the Vista IV unit for free.
What should I do if my 2020-2021 Aev ambulance is on this recall?
Check your VIN to confirm your specific ambulance is included in recall 20V783. If it is, contact the dealer handling the Halcore recall or call Halcore customer service at 1-800-447-0343. Reference Halcore recall number 20E-078 when you call. The replacement Vista IV unit is free.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost, and Halcore's remedy says dealers will provide updated replacement Vista IV units free of charge. Parts and labor are covered for included vehicles.
What is the safety risk?
The safety risk is delayed emergency response. If the LCD display locks up or stops working, emergency vehicle lighting and HVAC controls do not work as intended, which can delay emergency efforts and increase injury risk. The repair path is an updated replacement Vista IV unit.
When did the recall repair begin?
The recall repair began January 11, 2021. Since the remedy is available, owners of included vehicles can contact the dealer handling the Halcore recall or Halcore customer service at 1-800-447-0343 to arrange the free replacement Vista IV unit.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/20V783000 |
|---|---|
| Aev customer service | 1-800-447-0343 |
| NHTSA recall # | 20V783 |
| NHTSA recall # (full) | 20V783000 |
Source documents
-
Download Recall Document (PDF) (PDF) - Download Quarterly Report (PDF)
- Download Misc. Document (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 23, 2026. RecallNotify does not paraphrase NHTSA's consequence language; that text is reproduced as written above. Editorial standards →