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The IOX-RS232 allows external devices — gas detection monitors, weighing scales, or pressure monitors — to send data through the Geotab® GO device to MyGeotabTM.

Top Features

  • Geotab SDK integration facilitates data extraction from MyGeotab
  • Compatible with Geotab’s standard third-party protocol (

IOX RS232 Drawing CLOSE UP.png

IOX Hardware Technical Specifications


100 g


Overall Length: 1260 mm L

Widest Point: 34 mm W × 16 mm H


PC+ABS clamshell casing


CAN: 500 kb/s; for daisy chaining

RS232 Male/Female: 300 to 115,200 baud, parity, data bits, and flow control

RS232 Male/Female: 300 to 115,200 baud, 8 data bits, and 1 stop bit

Current Draw IOX-RS232

on GOx daisy chain

40 mA at 12 V / 24 V        Operating mode (typical/nominal current draw)

100 mA at 12 V / 24 V        Operating mode (max. current draw)

0.4 mA at 12 V / 24 V        Sleep mode (min. current draw)

Current Rating Operating Range

0.4 - 1.04A

Aux. Optional Power Source

1A Max (Red wire with PWR)

Temperature Rating

−40 ℃ to +85 ℃


Male Mini-USB Type-B connector: Daisy chain power and CAN in

Female Mini-USB Type-B connector: Daisy chain power and CAN out

DB9 Male (IOX-RS232M) or Female (IOX-RS232F)

Dual Wire: red and black wires used for third-party device power

DB9 RS-232 Black Male Connector

2. Purple - RX

3. Green - TX

4. Brown - DTR

5. Black/White - SGND

7. Grey - RTS

DB9 RS-232 Black Female Connector

2. Green - TX

3. Purple - RX

5. Black/White - SGND

6. Brown - DTR

8. Grey - RTS


Male Mini-USB connector connects to the GO Device or another IOX

DB9 connects to a serial device

Compatible Devices


(GO6 is not supported on IOXv3 design)

GO9 can source a maximum total current to the IOX in Daisy Chain

2500 mA at 12 V/24 V

Note: For each IOX in the Daisy Chain, add the Max Current draw, and do not exceed the Max.Total IOX Current draw.

IOX Installation Instructions

NOTE: Professional Installation Required — Installation of the IOX-RS232 requires the installer have sufficient technical knowledge and expertise for mobile device installation and integration into modern vehicles. i.e. Certified Geotab Advanced Installer certification.

WARNING! Prior to IOX-RS232 installation, read and follow GO device installation instructions ( to verify any existing GO device installation is correct in preparation for IOX-RS232 installation. Incorrect installation of either the GO device, and/or IOX-RS232 can result in loss of vehicle control and serious injury.

WARNING! Prior to IOX-RS232 installation, read and follow Important Safety Information and Limitations of Use, located at the end of the document. Always read and follow all safety information to prevent loss of vehicle control and serious injury.

How to Install IOX-RS232


Unplug the Geotab GO device from the vehicle and remove the IOX expansion port cover on the GO device.


Plug the 90° USB connector from the IOX in to the GO device. Secure the USB connector using a zip tie. Please note that over tightening the zip tie may damage the USB connector.

Note: Insert the USB connector in the orientation displayed in the image.


Choose an appropriate mounting location for the RS232 accessory.

Note: The location you choose for the GO Device influences the locations available to mount the accessory due to the wire length on the IOX-RS232. Please ensure the installation does not interfere with safe vehicle operation.


Connect the third-party device to the IOX-RS232 using the DB9 female or male connector.


The external red and black wires on the IOX-RS232 are used to supply power to a third-party device. The red wire connects to device power, and the black wire connects to device ground.

WARNING! The red and black IOX-RS232 wires are powered when the GO device is on. If they are not being used, ensure they are properly insulated to prevent any electrical hazard.

WARNING! Connecting the IOX-RS232 red and black wires to any vehicle power source may cause electrical heat/fire damage to the GO device, vehicle and/or serious burn injury. IOX-RS232 red and black wires must only be connected to provide power to a third-party device load.


Once you connect the IOX-RS232 to the GO device, plug in the GO device and immediately start the vehicle. The GO device enters debug mode.


Navigate to to verify that the device is communicating. In the space provided, enter your name, the company name, and the GO device serial number — found at the bottom of the device. Click Log Install.


After you click Log Install, the web page displayed the current communication status of the device — in GREEN or RED text. If the device is communicating, the status is displayed in GREEN text. If the device is not communicating, the status is displayed in RED text.

Note: If the device is not communicating, please ensure the device is installed correctly and try again.

Termination Shunt IOX V2 Housing.png

The IOX comes with a termination shunt installed in the expansion port. If you plan to install more than one IOX in a daisy chain, you must remove the shunt from each device in the line, with the exception of the last IOX connected. The shunt must remain in the last IOX and secured with a zip tie.

The shunt in the last IOX device ensures the GO device detects and configures the IOX, as effectively as possible.

NOTE: Failing to install the shunt in the last IOX could affect IOX communication. It is recommended that you secure the shunt using a zip tie if not already done.

Important Safety Information and Limitations of Use

For the latest version of Limitations of Use, please visit:

WARNING! Do not attempt to install, configure or remove any product from any vehicle while the vehicle is in motion or otherwise in operation. All installation, configuration or removal must be done only in stationary vehicles which are securely parked. Attempting to service units while being operated could result in malfunctions or accidents, leading to death or serious personal injury.

WARNING! All in-vehicle devices and related cabling must be securely fastened and kept clear of all vehicle controls, including gas, brake and clutch pedals. You must inspect devices and cab on a regular basis to ensure all devices and cabling continue to be securely attached. Loose cabling or devices may impede the use of vehicle controls, resulting in unanticipated acceleration, braking or other loss of vehicle control, which could lead to death or serious personal injury. Improperly fastened in-vehicle devices may detach and impact operators upon sudden acceleration or deceleration, which may cause injury.

WARNING! If at any point after an in-vehicle device is installed a warning light illuminates on the vehicle dash or the vehicle stalls or has a marked drop in performance, shut off the engine, remove the device, and contact your Reseller. Continuing to operate a vehicle with these symptoms can cause loss of vehicle control, and serious injury.

WARNING! Your in-vehicle devices must be kept clear of debris, water and other environmental contaminants. Failure to do so may result in units malfunctioning or short-circuiting that can lead to a fire hazard or vehicle damage or serious injury.

WARNING! Do not attempt to remove the devices from the vehicle in which they are originally installed for installation in another vehicle. Not all vehicles share compatibility, and doing so may result in unexpected interactions with your vehicle, including sudden loss of power or shutdown of the vehicle’s engine while in operation or cause your vehicle to operate poorly or erratically and cause death or serious injury and/or vehicle damage.

NOTICE: This product does not contain any user-serviceable parts. Configuration, servicing, and repairs must only be made by an authorized reseller or installer. Unauthorized servicing of these products will void your product warranty.

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