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Model year

2021 Proterra ZX5

Body and fuel not decoded. Owner complaints on file from no date to no date.

Recalls (6)Complaints (0)Investigations (0)Bulletins (103)
Recall campaigns covering this model year62,104 vehicles or units across those campaigns
Owner complaints0Not enough peers on file
Severity indexNoneCrash, fire, injury or death per 100
First 24 months0Complaints in its first two years
Complaints over time

Complaints about the 2021 Proterra ZX5 by year filed

Owner complaints about this model year, by the year they were filed with NHTSA.

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Source: NHTSA ODI complaints file. The lighter column runs through October.
Components

Complaints by component

Owner complaints by component. Hover or focus a bar for the crash, fire, injury or death count.

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Source: NHTSA ODI complaints file. A complaint can name more than one component; it is counted under the first.
Recalls

6 recall campaigns cover the 2021 Proterra ZX5

Check a specific vehicle by VIN on NHTSA's site: a campaign may cover only part of a model year's production.

Recall campaigns for the 2021 Proterra ZX5
CampaignFiledSubjectComponentVehiclesRemedy
24V-655Sep 6, 2024Vehicle controller software may allow the electrical circuit for the radiator fan to overheatElectrical system483Software update
23V-697Oct 17, 2023Transistor inside the inverter may overheat and fail, which can result in a loss of power steering and drive powerElectrical system238Part replacement
23V-078Feb 13, 2023Windshield wiper motors may operate intermittently or may fail to operateVisibility and wipers252Part replacement
22V-855Nov 18, 2022Back pressure in the shared air exhaust for the pneumatic ride height system and parking brake control valve may engage the parking brake while…Brakes386Repair or modification
22V-114Feb 28, 2022Plexus adhesive between the torque limiter plate and the bus body may be insufficient, causing the bolts that secure the steering gearbox to loosenSteering724Repair or modification
21V-040Feb 1, 2021These vehicles have a front fender flare which may cause mud, dirt, debris, rain and snow to splash onto the driver's side window and mirrorStructure21Repair or modification
Source: NHTSA ODI recalls file.
Look up a VIN at NHTSA
Owner complaints

What owners reported about the 2021 Proterra ZX5

The full text of every complaint filed with NHTSA about this model year, newest first. Complaints are filed by owners and are not verified by NHTSA; NHTSA removes personal details before publishing.

0 complaints on file.

    Source: NHTSA ODI complaints file.
    Investigations

    NHTSA has not opened an investigation on this model year

    Source: NHTSA ODI investigations file.
    All investigations
    Service bulletins

    103 manufacturer communications cover this model year

    Technical service bulletins and other notices the manufacturer sent to dealers. A bulletin is not a recall; the 60 most recent are listed.

    • SC-21-151 Jan 21, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair to the air compressor, adding a snorkel to relocate the air intake to get cleaner air into the compressor.
    • SC-21-162 Dec 21, 2021 · Service Bulletin/Repair Instructions
      Pin location change on an ECU to properly assign both doors open signal and the horn relay signal.
    • SC-20-064 Oct 13, 2020 · Service Bulletin/Repair Instructions
      Transit bus repair to the aux heat convectors to secure wiring harness, it was found the previous adhesive material used would debond when heated.
    • SC-20-140 Jun 1, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair for the rear door VIP sensors. This repair provides a clip to go behind the sensor to keep it from falling down.
    • SC-20-148 Sep 1, 2021 · Service Bulletin/Repair Instructions
      Transit bus steering column maintenance document to supplement maintenance and repair manual.
    • SC-20-155 Feb 15, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to a coolant line under the rear hatch. New part in document is a molded hose to prevent hose from chaffing on the rear hatch.
    • SC-20-159 Mar 11, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the side windows to include a larger sealing gasket to prevent water from entering cabin.
    • SC-21-001 Nov 12, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the wheel well compartment hinge. The compartment lid was previously bonded on, this repair instructions updates the vehicle to use fasteners as well.
    • SC-21-008 Feb 19, 2021 · Service Bulletin/Repair Instructions
      Transit bus drive axle retrofit to replace a lock washer on the transmission.
    • SC-21-020 Feb 16, 2021 · Service Bulletin/Repair Instructions
      Transit vehicle software update to the body controller and vehicle controller. Improving visibility on the dash to LV battery voltage and ABS on the dash will flash when active.
    • SC-21-034 Sep 21, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the air compressor, the previous banjo fitting was prone to leaking, the solid drain plug prevents compressor from losing oil.
    • SC-21-045 Mar 18, 2021 · Service Bulletin/Repair Instructions
      Transit bus torque verification on the intermediate steering shaft.
    • SC-21-048 Aug 30, 2021 · Service Bulletin/Repair Instructions
      Transit bus fleet check to inspect the steering gearboxes and replace hardware.
    • SC-21-056 May 20, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the HVAC, the supply air temperature sensor is being replaced to improved sealed sensor provided by our HVAC OEM. The sensor failure prevents the HVAC from running.
    • SC-21-058 Jul 15, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the rear mud flaps to eliminate a gap to reduce road grime from entering the rear trunk of the vehicle.
    • SC-21-060 Sep 9, 2021 · Service Bulletin/Repair Instructions
      Transit bus rear axle cover bolt replacement. The hardware originally installed had the wrong coating for the harness road grim.
    • SC-21-077 Jun 4, 2021 · Service Bulletin/Repair Instructions
      Transit bus software update to the batteries, charge controller and vehicle controller. Fixes coolant level LEDs, ESM updated specific parameters around temperatures and auto pack configuration, BMS SW resolves brick imbalance, min/max humidity levels.
    • SC-21-086 Aug 17, 2021 · Service Bulletin/Repair Instructions
      Transit bus software update to the batteries, charge controller and vehicle controller. Fixes coolant level LEDs, ESM updated specific parameters around temperatures and auto pack configuration.
    • SC-21-087 Jun 23, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair for horn relays, improved horn relay installed during retrofit.
    • SC-21-097 Sep 8, 2021 · Service Bulletin/Repair Instructions
      Transit bus torque verification on the 3 phase power junction box for the air compressor.
    • SC-21-106 Sep 22, 2021 · Service Bulletin/Repair Instructions
      Transit bus software to fix bugs and reduce nuisance faults. Creates new EEPROMs for specific customer requests also updates logic for vehicles exterior lights to have cornering lights while in night mode.
    • SC-21-112 Oct 27, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the vehicles wiper switch, the switch is replaced in this bulletin to improve reliability as the switch was stuck on.
    • SC-21-121 Aug 26, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair, retrofit adds guard to prevent horn from accumulating road debris.
    • SC-21-128 May 2, 2023 · Service Bulletin/Repair Instructions
      Transit bus repair for the ADA ramp brackets, new method to secure the interior body mounting brackets for the front door ramp.
    • SC-21-139 Dec 1, 2021 · Service Bulletin/Repair Instructions
      Transit bus software update the HVAC controllers from our supplier. Adds additional protection from over current and logic for the heater safety switch faults that can occur on shutdown and restart.
    • SC-21-142 Nov 22, 2021 · Service Bulletin/Repair Instructions
      Transit bus software update to the body controller, when flashing the EEPROMs were auto setting to 238 not 0 when a new EEPROM was loaded on the vehicle. Then fixing a bug where the door entrance lights were not 100% brightness when doors were in use.
    • SC-21-143 Jan 20, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair at the battery thermal management system in which the U bracket is being replaced due to cracking.
    • SC-21-147 Oct 13, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair for rear modesty panel to replace wall bracket that is prone to cracking.
    • SC-21-148 Dec 6, 2021 · Service Bulletin/Repair Instructions
      Transit bus powertrain software update to support the product to shift smoothly and reduce nuisance faults.
    • SC-21-158 Apr 22, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair for the ADA ramp closeout bracket on the exterior of the bus. The replacement part is made from stainless steel reducing the previous mild steel that was corroding.
    • SC-21-159 Jan 22, 2022 · Service Bulletin/Repair Instructions
      Transit bus bulletin to install snorkel to air compressor to prevent water and road grim from entering the intake.
    • SC-21-161 Aug 16, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair at the rear doors, door seal is screw into the body. This repair procedure includes installing inserts into the body to keep seal from coming loose.
    • SC-21-166 Apr 25, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair for exterior compartments gas strut brackets. Document provides instruction to improve the securement of the fixed brackets.
    • SC-21-170 Feb 2, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair instruction for compartment for an extended latch catch.
    • SC-21-174 Jan 5, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair on the high voltage batteries. An improper ground screw might have been installed causing the battery to go offline and reduce range of the vehicle.
    • SC-21-178 Mar 3, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair to exterior connectors that were not sealed, repair instructions to add sealed connectors to radiator fans.
    • SC-21-179 Mar 3, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair to the prodrive harness wrong terminal sizes were used. Repair instructions update the harness.
    • SC-21-181 Mar 22, 2022 · Service Bulletin/Repair Instructions
      Transit bus inspections for shipping blocks installed in egress windows to ensure proper closing/latching.
    • SC-21-183 Jan 27, 2022 · Service Bulletin/Repair Instructions
      Transit bus repair instructions to install a drain in the cavity where the ADA ramp sits.
    • SC-22-003 Feb 26, 2022 · Service Bulletin/Repair Instructions
      Transit bus procedure to inspect torque strips on the steering gearbox and record breakaway values then replacing the hardware and using blue loctite to reinstall.
    • SC-22-135 Jan 18, 2023 · Service Bulletin/Repair Instructions
      Transit bus repair to the overhead destination sign, the replacement frame includes extra gussets in the corners of the frame.
    • SC-21-027 Mar 12, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair to the rear doors, instruction provided require a new bolt to be added to the mechanism.
    • IB-22-136 Apr 13, 2023 · Service Bulletin/Repair Instructions
      Transit bus air compressor inspection to verify if failed compressor is can be repaired or rebuilt.
    • SC-21-050 Apr 21, 2021 · Service Bulletin/Repair Instructions
      Transit bus reliability improvement for the air intake of the auxiliary heater to intake fresher air.
    • SC-22-115 Mar 27, 2023 · Service Bulletin/Repair Instructions
      Repair instructions for transit buses to replace the destination sign bracket hardware to nylocks.
    • SC-23-070 Sep 21, 2023 · Service Bulletin/Repair Instructions
      Transit bus body work repair instructions to support destination side delamination repair.
    • SC-21-029 Jan 13, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair instructions for the duo drive axle in the event one of the wheelends fail this document supplements the rebuild.
    • SC-21-176 Nov 8, 2022 · Service Bulletin/Repair Instructions
      Transit bus torque update to HVJB in the rear trunk of the bus.
    • SC-21-123 Oct 26, 2021 · Service Bulletin/Repair Instructions
      Transit bus repair for rooftop coolant line that was collapsing reducing coolant flow.
    • SC-23-001 Mar 28, 2023 · Service Bulletin/Repair Instructions
      Transit bus repair instruction to install new fasters on the destination sign for improved durability.
    • SC-21-103 May 24, 2022 · Service Bulletin/Repair Instructions
      Repair instructions for rooftop passthrough if wires have heat damage. Related to 24V-655, prior to remedy.
    • SC-21-149 Dec 8, 2022 · Service Bulletin/Repair Instructions
      On the transit battery electric buses it was found that some of the HV batteries had a configuration improperly set causing the battery to not balance correctly reducing the vehicles range.
    • SC-21-019 Feb 13, 2021 · Service Bulletin/Repair Instructions
      Transit vehicle repair instructions for replacing a ride height manifold due to EMI sensor failures.
    • FC-24-020 Dec 9, 2024 · Service Bulletin/Repair Instructions
      Transit Vehicle inspection of the DC cables to ensure all split blocks and swivel bundle spacers are installed.
    • FC-22-092 Aug 16, 2022 · Service Bulletin/Repair Instructions
      Fleet check/repair instructions heavy duty transit to inspect for air lines installed in the wrong order.
    • FC-22-093 Aug 16, 2022 · Service Bulletin/Repair Instructions
      Fleet check and repair instructions for the heavy duty electric transit vehicles to ensure the door pressure is in the optimal range.
    • FC-22-100 Nov 28, 2022 · Service Bulletin/Repair Instructions
      Inspection and repair instructions for heavy duty transit buses specifically looking at brake lines due to chaffing seen at a customer site.
    • FC-22-157 Oct 12, 2022 · Service Bulletin/Repair Instructions
      Fleet check repair instruction for heavy duty transit buses to inspect for connector between interlock and ATC being installed in the wrong location.
    • FC-23-003 Oct 2, 2023 · Service Bulletin/Repair Instructions
      Repair instruction to inspect heavy duty transit vehicles for humidity in the battery pack and perform preventative maintenance.
    • FC-23-006 Nov 29, 2022 · Service Bulletin/Repair Instructions
      Repair instructions for the telemetry system on the heavy duty transit buses if the system is not reporting.
    Source: NHTSA manufacturer communications files.
    About service bulletins