CTIS Controller and Display Compared: AirUp vs TIREBOSS 2
The controller is the part of a central tire inflation system a driver actually touches. It is also the part where these two systems are documented very differently: the AirUp display is a Grayhill Series 3D70, so its hardware specification is published in a third-party datasheet anyone can check. TPC International publishes electrical, environmental and system-interface figures for TIREBOSS 2 as a whole, but no hardware specification for its Operator Control Unit.
Both are below, each cited to published material. Where a figure is not published, this article says so rather than estimating it.
Controller comparison table
| Specification | AirUp / AirDown control unit | TIREBOSS 2 Operator Control Unit (OCU) |
|---|---|---|
| Display hardware | Grayhill Series 3D70 7-inch CAN bus display | Not published |
| Interface type | 7″ transmissive IPS LCD touchscreen, backlit | Touchscreen — “Interactive touch screen display”; the service manual calls the OCU “basically a specialized touchscreen computer” |
| Resolution | WVGA, 800 × 480, 16:9 | Not published |
| Brightness | 1000 nits (cd/m²), software-controlled LED backlight | Not published |
| Colour depth | 16-bit | Not published |
| Touch technology | Projected capacitance — works wet and with gloves | Not published |
| Cover lens | Scratch-resistant glass, not plastic; optically bonded to the LCD; anti-glare coating | Not published |
| Processor | Freescale/NXP i.MX6, 800 MHz | Not published |
| RAM | 512 MB DDR3 | Not published |
| Onboard storage | 4 GB flash | Not published |
| Boot time | 3 seconds | Not published |
| Ingress protection | IP67 front and rear, with mating connector installed | Not published |
| Mounting | In-cab, dash-mounted — not exposed to the weather | In-cab — “Located in the truck cabin”, “Mounting on dash”; ignition power taken “inside cab” |
| Display operating temperature | −30 °C to +65 °C (−22 °F to +149 °F), per ANSI/ASAE EP455 5.1.1 | Not published for the OCU |
| Display storage temperature (cold soak) | −40 °C to +85 °C (−40 °F to +185 °F) | Not published for the OCU |
| System operating temperature | Not published | −40 °F to +125 °F, quoted for the system |
| Operating voltage | 8–32 VDC; jump-start tolerant to 36 V for 5 minutes; reverse-polarity and short-circuit protected | 11 V to 36 V, quoted for the system |
| Power draw | 7 W typical, <1 mA standby | Not published |
| Environmental qualification | ANSI/ASAE EP455 vibration, shock, 400 mm drop, 96% humidity, salt fog, thermal shock, wash-down and altitude; SAE J1455 sand and dust; CISPR25 Level 3 conducted emissions | Not published |
| Ports on the display unit | USB 2.0 host, RS232, CAN 2.0B, Ethernet, audio line out, digital and analog I/O (fitted by variant) | RS-485 to the System Control Unit; Wi-Fi radio |
| Camera inputs | Up to three NTSC/PAL camera inputs; 360° camera system on the AirDown configuration | None documented — the TB2 Service Manual v2.4 mentions video only as an on-screen driver training clip, and the product page lists no camera input |
| System serial interface | Not published | RS485 for the control system (CAN bus capable); RS232 or USB for external data loggers |
| Wireless | Not published | Wi-Fi radio for data transfer and program updates |
| GPS | Not published | Yes — the OCU supplies vehicle speed, location and time to the system |
| Onboard diagnostics | Pass/fail system check in real time | Diagnostic Mode (manual valve inflate/deflate, heater test, live supply and valve pressures); alarm-code diagnostic chart; OCU diagnostic lights |
| Fault / warning history | Warnings stored and retrievable at any time | System Control Unit acts as a “black box” data recorder; optional external data logger |
| Set-point lockout | Pressure set points password-protected for the fleet manager | Maintenance Settings screen is password-protected |
| Firmware update method | From a USB drive, at the truck | Over Wi-Fi; the manual instructs the technician to “contact TPC International Service department for required updates to be installed” |
| Independently controlled tire groups | Not published | Up to four — one Valve Control Unit per tire group, on a daisy-chained LIN bus |
| Pressure accuracy | Not published | ±2 psi nominal |
| Control valve flow capacity | Not published | Up to 75 CFM (2124 L/min) |
| Driver training video on screen | Not published | Yes — “Operator video embedded in controller” |
| Controller patent | US 11,529,831 B2, granted 2022-12-20, assignee Airdown Inc | Not addressed here |
A note on what is being compared
One caveat belongs up front, because it affects how the table should be read. The AirUp column describes the display unit, specified in a component datasheet. The TIREBOSS column describes what TPC International publishes for the TIREBOSS 2 system, because TPC publishes no hardware specification for its Operator Control Unit at all.
Two rows are therefore not like-for-like, and the honest reading favours neither side uniformly:
- Temperature. The AirUp figures are display ratings: −30 °C to +65 °C (−22 °F to +149 °F) operating, −40 °C to +85 °C (−40 °F to +185 °F) storage. TPC’s −40 °F to 125 °F is a system figure covering hardware that lives outside — valves, plumbing, wheel ends. TPC publishes no operating temperature for the OCU itself, so there is no display-to-display comparison to make here.
- Voltage. The AirUp display accepts 8–32 VDC and tolerates a 36 V jump start for five minutes. TPC publishes an 11–36 V system range. Both cover 12 V and 24 V vehicles.
What the AirUp control unit publishes
The AirUp display is a Grayhill Series 3D70, a 7-inch CAN bus display built for off-highway vehicles. Because it is a documented product in its own right, every hardware figure below can be checked against Grayhill’s datasheet (Rev. 2025/08) rather than taken on our word.
The panel is a 7-inch transmissive IPS LCD at WVGA 800 × 480 with 16-bit colour and a software-controlled LED backlight rated at 1000 nits. Brightness is the number that matters most in a cab, and 1000 nits is a daylight-readable panel. The cover lens is scratch-resistant glass rather than plastic, optically bonded to the LCD — bonding improves impact resistance and cuts the internal reflections that wash a screen out in direct sun — with an anti-glare coating on top. The touchscreen is projected capacitance and works with wet fingers and with gloves on.
Behind the glass is a Freescale i.MX6 running at 800 MHz with 512 MB of DDR3 RAM and 4 GB of flash storage, a USB 2.0 host port, and a battery-backed real-time clock. It boots in about three seconds.
The ruggedisation is the part worth reading closely if your trucks work in dust, mud or wash bays. The unit is sealed to IP67 front and rear with the mating connector installed, and it is qualified to ANSI/ASAE EP455 — the agricultural-equipment environmental standard — for random and sinusoidal vibration, 490 m/s² shock in three axes, a 400 mm drop onto a hardwood bench, 96% humidity at 35 °C for 240 hours, 48 hours of salt fog, thermal shock, wash-down and altitude, plus SAE J1455 sand and dust. It draws 7 W typical, under 1 mA on standby, survives a 36 V jump start for five minutes, and is protected against reverse polarity and short circuit.
The display is dash-mounted inside the cab, so it is never exposed to the weather directly. What the sealing and vibration ratings actually buy you is tolerance for the things that do reach an in-cab screen: dust, spilled coffee, a pressure washer during interior cleaning, road shock, and a cold soak overnight in an unheated truck. The −40 °C storage rating is the relevant number for that last one.
Two software behaviours are worth calling out, because they change what a mechanic does on a bad morning:
- Diagnostics are pass/fail. The unit runs a system check and reports each item as passing or failing, rather than leaving a technician to infer a fault from behaviour.
- Warnings are stored. A warning that appeared overnight is still there in the morning and can be retrieved from the screen.
Pressure set points are password-protected, so a fleet manager sets them and a driver cannot change them. The 3D70 platform carries up to three NTSC/PAL camera inputs, which is how the AirDown configuration puts a 360° camera system on the same screen the driver already uses for tire pressure.
The control unit is covered by US Patent 11,529,831 B2 (“Central tire inflation system”, granted December 20, 2022, assignee Airdown Inc), a continuation of US 10,493,808 B1 sharing its July 26, 2017 priority date. That patent covers the control system, not the display module.
What the TIREBOSS 2 OCU publishes
TPC International documents the TIREBOSS 2 architecture in detail. The system is three parts: the Operator Control Unit, the System Control Unit, and one or more Valve Control Units. The manual describes the OCU as providing “the operator interface to the system allowing configuration, selection of operating modes, reporting of alarm conditions, data logging, remote access and system maintenance functions”, and states plainly that it “is basically a specialized touchscreen computer” (TB2 Service Manual v2.4, System Descriptions, p. V, accessed August 17, 2026).
The OCU also carries a GPS receiver. Vehicle speed from that receiver is used to enforce speed limits tied to the selected pressure, and to trigger automatic re-inflation in an overspeed condition (TB2 Service Manual v2.4, pp. V and VI). It communicates with the System Control Unit over RS-485 and carries a Wi-Fi radio for data transfer and program updates (p. V). The TIREBOSS product page lists RS485 for the control system (CAN bus capable) and RS232 or USB for external data loggers (accessed August 17, 2026).
Data recording sits in the System Control Unit rather than in the display: the manual describes the SCU as serving “as a ‘black box’ data recorder for critical system information” and providing the interface to an optional external data logger (TB2 Service Manual v2.4, p. V).
Up to four Valve Control Units can be fitted, each controlling pressure in one defined group of tires, communicating with the SCU over a daisy-chained LIN bus, and each providing automatic heater control to prevent valve icing (TB2 Service Manual v2.4, p. V).
What TPC does not publish: screen size, resolution, brightness, colour depth, touch technology, cover lens material, processor, memory, storage, ingress protection rating, or environmental qualification standard for the OCU. None of it appears on tireboss.com/product/ or anywhere in the TB2 Service Manual v2.4 (both accessed August 17, 2026). If those numbers matter to your comparison, they have to come from TPC directly.
Set-point lockout: both systems have it
Both controllers protect critical settings behind a password.
On AirUp, the protected setting is the pressure set point itself, under fleet-manager control. On TIREBOSS 2, the protected screen is the Maintenance Settings screen, described in the manual as “a password protected screen where critical system settings can be altered” (TB2 Service Manual v2.4, OCU Operations, p. 3-1, accessed August 17, 2026). Enabling or disabling applications and activating configurations both trigger that password prompt (pp. 3-3 to 3-5).
If the requirement is “a driver cannot change tire pressures”, both systems meet it as documented.
How an update reaches the truck
TIREBOSS 2 updates over Wi-Fi. The published procedure is: get the truck within reach of a reliable Wi-Fi network, connect the OCU to it, and then “contact TPC International Service department for required updates to be installed” (TB2 Service Manual v2.4, Firmware/Software Updates, p. 4-7, accessed August 17, 2026). The manual also documents a fallback in which the technician creates a phone hotspot with a specific network name so the OCU will connect (pp. 3-8 to 3-9). A firmware mismatch between OCU and SCU raises a version error that must be cleared before the system runs normally (pp. 4-3 to 4-4).
AirUp and AirDown firmware is updated from a USB drive. The display carries a USB 2.0 host port, the update is done at the truck by your own technician, and no network connection is required.
Related reading
- CTIS Wheel-End Valve Service: What It Really Takes — the rebuild side of the same comparison.
- TPMS vs. a tire pressure control system — why monitoring and control are not the same thing.
Frequently asked questions
What display does the AirUp control unit use?
A Grayhill Series 3D70 7-inch CAN bus display: a 7-inch transmissive IPS LCD at 800 × 480 with 16-bit colour, a 1000-nit LED backlight, projected-capacitance touch that works wet and gloved, an optically bonded scratch-resistant glass cover lens, an 800 MHz i.MX6 processor, 512 MB DDR3 RAM and 4 GB of flash storage, sealed to IP67 front and rear.
Does TIREBOSS publish the screen size or processor of its controller?
No. Neither tireboss.com/product/ nor the TB2 Service Manual v2.4 states the Operator Control Unit’s screen size, resolution, brightness, processor, RAM or storage (both accessed August 17, 2026). The manual describes it as “basically a specialized touchscreen computer” and the product page as an “Interactive touch screen display”.
Is the AirUp display sealed against water and dust?
Yes — IP67 front and rear with the mating connector installed, and qualified to ANSI/ASAE EP455 for wash-down, 96% humidity, salt fog, vibration, shock and a 400 mm drop, plus SAE J1455 sand and dust (Grayhill Series 3D70 datasheet, Rev. 2025/08). TPC does not publish an ingress protection rating for the TIREBOSS 2 OCU.
Will the display survive a northern winter?
Both systems put the display in the cab, so it never sees the weather directly. The AirUp display is rated to −40 °C (−40 °F) in storage, which is the number that covers a truck parked outside overnight, and is rated to operate from −30 °C (−22 °F) upward once powered. TPC’s published −40 °F to 125 °F figure is for the TIREBOSS system as a whole; no operating temperature is published for its Operator Control Unit.
Where is the display mounted?
In the cab on both systems. The AirUp display is dash-mounted inside the cab and is not exposed to the weather. TPC’s schematics likewise show the OCU “Located in the truck cabin” with “Mounting on dash” and ignition power taken “inside cab” (TB2 Service Manual v2.4, System Schematics, accessed August 17, 2026).
How are TIREBOSS 2 firmware updates installed?
Over Wi-Fi. The TB2 Service Manual v2.4 directs the technician to connect the Operator Control Unit to a reliable Wi-Fi network and then contact TPC International’s service department to have the update installed (p. 4-7, accessed August 17, 2026).
Can a driver change the tire pressure settings?
Not on either system as documented. AirUp password-protects the pressure set points under fleet-manager control. TIREBOSS 2 password-protects the Maintenance Settings screen where critical system settings are altered (TB2 Service Manual v2.4, p. 3-1, accessed August 17, 2026).
How many tire groups can a TIREBOSS 2 system control independently?
Up to four. Each Valve Control Unit controls one defined group of tires and communicates with the System Control Unit over a daisy-chained LIN bus (TB2 Service Manual v2.4, p. V, accessed August 17, 2026).
Can the AirUp screen show a camera feed?
Yes. The 3D70 platform supports up to three NTSC/PAL camera inputs, and the AirDown configuration integrates a 360° camera system into the same display used for tire pressure. TPC’s documentation describes no camera or video input for the TIREBOSS 2 OCU — the only video referenced in the TB2 Service Manual v2.4 is an on-screen driver training clip (pp. 3-1 to 3-2, accessed August 17, 2026).
How fast does the AirUp display boot?
About three seconds (Grayhill Series 3D70 datasheet, Rev. 2025/08). TPC publishes no boot or start-up time for the TIREBOSS 2 OCU.
How is AirUp firmware updated?
From a USB drive. The display has a USB 2.0 host port, and the update is performed at the truck by your own technician with no network connection required.
Sources
- Grayhill Series 3D70 7-inch CAN Bus Display datasheet, Rev. 2025/08 — grayhill.com (accessed August 18, 2026)
- AirUp system specifications — https://airdownyourtires.com/airup-system/ (accessed August 17, 2026)
- TIREBOSS product specifications — https://www.tireboss.com/product/ (accessed August 17, 2026)
- TIREBOSS TB2 Service Manual, Version 2.4, current as of January 2025 — PDF on tireboss.com (accessed August 17, 2026)
- US Patent 11,529,831 B2 — Google Patents
- US Patent 10,493,808 B1 — Google Patents
Specifications on both sides are quoted as published on the access dates above. Manufacturers revise documentation; check the current source before making a purchase decision. Questions about the AirUp or AirDown controller can go to our contact page.
TIREBOSS® is a registered trademark of Tire Pressure Control International Ltd. AirDown Inc is not affiliated with, authorized by, or endorsed by Tire Pressure Control International Ltd. Grayhill is a trademark of Grayhill, Inc. Trademark references are for identification and comparison only.