GODIAG GT100 OBDII ECU Breakout Box: manual, how-to guide

GODIAG GT100 OBDII ECU Breakout Box becomes a hot-selling product in obdii365.com since September, the poster would like to share all details about it incl. what’s GODIAG GT100, what it can do, how to use it, how to use it to connect with kinds of OBDII /EOBD diagnostic tools / ECU programming tools.

Godiag Gt100 Obdii Ecu Breakout Box Guide 01

Godiag GT100 Package includes:

Host: 1pc

OBD 2-in-1 extension cable: 1pc

Colored jumper cable: 1pc

Power supply 12V: 1pc

Resistance 120 ohm: 1pc

Banana plug: 6pcs

Wire accessories, Dupont 2.54mm connector female pins: 24pcs

–> GODIAG GT100 OBDII ECU Breakout Box unboxing video:



What’s GODIAG GT100 designed for?

GODIAG GT100 OBDII ECU Breakout Box is a latest testing platform for OBDII protocol communication detection and ECU maintenance / diagnosis / programming / coding. It can convert the car OBD2 interface into 16 pin for signal detection and electrical level  conversion. Able to connect the single modules or multiple modules of the vehicle. It can be connected with any diagnostic tool to tell whether the car communication is good or not. It can also supply power to the car when you change the battery to avoid the vehicle control module data being lost, automatically locked, the key remote control fails and the fault light turns on.

Godiag Gt100 Obdii Ecu Breakout Box Guide 02


GODIAG GT100 Highlights:

 GT100 – OBDII Protocol Detector

 GT100 – ECU connection

 GT100 – Compatible with lots of devices

 GT100 – Convert OBD1 diagnostic interface to the standard OBD2 diagnostic

 GT100 –Multi-ECU connection mode

 GT100 –The cable can be extended.

 GT100 – Power the car when changing the battery

 GT100 –Optional dedicated adapter

Guarantee: One year warranty.


Look at this image on how to connect Godiag GT100 to any of diagnostic tool / ECU programming tool, the car , the computer, the ECU and the Oscilloscope.

Godiag Gt100 Obdii Ecu Breakout Box Guide 03


->> How to connect Godiag GT100 to the ECU and Vident scanner to read codes & Data Stream:



Godiag GT100 Parameter:

Diagnostic port: OBDII

Working voltage: DC 9V-24V

Work and power: 0.5-0.6W

Adapter power: Input AC100v-240v, Output DC12V 1A

Operating temperature range:-20 to 70 °C ( -4 to 158 °F )

Storage temperature range: -40 to 85 °C ( -40 to 185 °F )

Dimension: L: 23cm, W:18cm, H:7cm


What will Godiag GT100 do and how to do?

– By connecting the vehicle and diagnostic tool via OBDII, Godiag GT100’s LED will indicate whether the OBDII diagnostic interface has a good communication with the car.

Godiag Gt100 Obdii Ecu Breakout Box Guide 04


Monitor the voltage of vehicle OBDII interface and display it in real time. If it is less than 11V, please stop the diagnosis and programming to avoid the vehicle being unable to start/data loss/module locked.

Godiag Gt100 Obdii Ecu Breakout Box Guide 05


Indicator Meaning:

  1. Manufacturer custom
  2. SJE1850 wire<bus+>
  3. Manufacturer custom
  4. Power grounding
  5. Signal grounding
  6. SAEJ2284《CAN》high
  7. ISO9141-2&iso, DIS4230-4K wire
  8. Manufacturer custom
  9. Manufacturer custom
  10. SJE1850 wire《bus->
  11. Manufacturer custom
  12. Manufacturer custom
  13. Manufacturer custom
  14. SAEJ2284《CAN》low
  15. ISO9141-2 & ISO/DIS 4230-4L wire
  16. Car battery positive


  1. OBDII Protocol Detector & communication detection

Godiag Gt100 Obdii Ecu Breakout Box Guide 06


1). Connect GODIAG GT100 to the OBDII diagnostic port of the car.

2). When the device displays the voltage, turn on the power switch of GODIAG GT100.

3). Then connect to the diagnostic tool, when the tool is communicating with the car, the LED indicator of corresponding protocol will light up or flash. ( If the CAN protocol is detected, it will have the maximum brightness. When the communication is successful, the corresponding CAN-H and CAN-L will dim or twinkling weakly)


  1. ECU connection: single module connection

GODIAG GT100, connected to a single ECU module, is convenient for a user to do the single-module diagnosis and programming.

Godiag Gt100 Obdii Ecu Breakout Box Guide 07


1). Connect the ECU with the color jumpers. (If the ECU is CAN protocol, please check whether you will need to connect a 120 ohm resistor.)
2). The Godiag GT100 can be powered by connecting to the OBDII diagnostic interface of car, or by an AC power adapter.
3). To diagnose and program for a single ECU by connecting the diagnostic tool or ECU programmer.


  1. Banana plug extension connection: Extend the car’s OBDII 16pin interface to tell you whether the OBDII interface connection is good or not, which is convenient for the test of OBDII interface voltage waveform.

Godiag Gt100 Obdii Ecu Breakout Box Guide 08


  1. Convert OBD1 diagnostic interface to the standard OBD2

Use the connector to convert the OBD1 interface into obd2 interface according to the diagnostic interface communication protocol.

Godiag Gt100 Obdii Ecu Breakout Box Guide 09


  1. Connect multiple ECU control modules at the same time, which is convenient for the professional engineers to detect and maintain.

Godiag Gt100 Obdii Ecu Breakout Box Guide 10


  1. When to use the extension cables: The space of the diagnostic interface location is too narrow to connect to the diagnostic tool, or the user find that the diagnostic cable is not long enough during maintenance. It can be extended by 1.2 meters.

Godiag Gt100 Obdii Ecu Breakout Box Guide 11


  1. Able to power the car when replacing the used battery.

Godiag Gt100 Obdii Ecu Breakout Box Guide 12


1). Prepare battery A to supply power by connecting to No. 16 / 4 / 5 holes of Godiag GT100 & to the OBD2 diagnostic interface of the car.

[Notice 1. Turn on the power switch of Godiag GT100. 2. Don’t turn on the ignition switch, don’t start the car]

2). Then replace the brand-new battery B with the used battery in the car, which will ensure that the car has fully power to prevent data loss and audio lock-up or the malfunction due to lack of power to the ECU control module.


  1. The dedicated adapter will be released (help GT100 connect to the special ECU module)

Godiag Gt100 Obdii Ecu Breakout Box Guide 13



Please read the following statement carefully:

GODIAG GT100 Overview will help you quickly master how to use GT100 equipment. Please abide by national laws and do not use it for illegal purposes.

GODIAG GT100 Overview is written by GODIAG, please do not use it for any commercial purposes without authorization.

Please abide by national laws. we are not responsible for any illegal usage of GODIAG equipment.


Safety precautions
To avoid personal injury, vehicle / equipment damage, please read this manual first. There are some safety precautions should be followed when working on the vehicle:


1) Always work in a safe environment

2) Wear the goggles that comply with ANSI standards.

3) Ensure that clothes, hairs, hands, tools and equipment are kept away from the running engine parts or the hot engine parts.

4) Ensure that the working area is well-ventilated because the vehicle exhaust is toxic.

5) Place bricks in front of all wheels to prevent accidental movement of the vehicle.

6) During testing and working, someone must supervise the vehicle.

7). Be extremely careful when working near the ignition coil, distributor cap, ignition wire, spark plug, these components will generate dangerous voltage.

8) Shift to P gear (for an automatic transmission car) or N gear (for a manual transmission car), and ensure that the parking brake is in the active state (pull up the handbrake).

9) Make sure there is a fire extinguisher suitable for gasoline/chemical/electrical nearby.

10) Do not plug or unplug the device when the ignition is turned on or the engine is working.

11) Keep the equipment dry and clean, and avoid contact with oil, water or grease. Please clean the equipment with a clean cloth and gentle detergent.


Hottest-selling GODIAG GT100 OBDII ECU Breakout Box is here: