GODIAG GT105 II – OBD Break Out Box for ECU Diagnosis

The Newest GODIAG GT105 II is an upgraded OBD2 Break Out Box that makes it easier and safer to work with ECU diagnostics, programming, and advanced troubleshooting via the vehicle's OBD2 port – both in the workshop and in the field. The GT105 II displays the vehicle's voltage directly on the device and can also warn of low battery voltage (alarm below 11V), which is especially valuable during programming and sensitive sessions where stable voltage is crucial.

It features clear communication indicators for common signals/protocols: PWM+ (PIN2), CANH (PIN6), CANL (PIN14), and K-line (PIN7). When data is communicated, the respective indicator flashes, allowing you to quickly assess whether your diagnostic/programming equipment is actually "talking" to the car. The GT105 II also offers separated ground points via OBD2 PIN4 (Body GND) and PIN5 (Signal GND), as well as a function where PIN4 and PIN5 can be switched between shorted and non-shorted – practical for special cases and certain programming scenarios.

A major strength is that the GT105 II can draw power from the car's battery and convert it to a stable DC12V supply via a DC connector (5.5×2.5 / 5.5×2.1) with a resettable 7A fuse and robust cable (0.75 mm², 2-conductor). This makes it perfect for outdoor jobs / on-site maintenance when you need to power diagnostic equipment without a wall outlet. The device can also be used as an OBD Battery Replacement Tool to maintain power during battery replacement and reduce the risk of data loss. The GT105 II is a tool for serious troubleshooters who want control over voltage, communication, and power supply – in a compact format. ✅

Introduction – what is an OBD Break Out Box and why is the GT105 II so useful?

An OBD Break Out Box (also called an OBD test box or OBD breakout) is a tool that sits between the car's OBD2 socket and your diagnostic/programming equipment. The idea is simple: you get more control, better overview, and the ability to measure/indicate what is happening on relevant pins – while also being able to power external equipment from the car battery when working outdoors.

The GODIAG GT105 II is the upgraded version of the GT105 and has been enhanced with 5 new functions:

• Vehicle voltmeter: displays the vehicle's voltage.
• CR2032 test: tests the car's remote control battery (CR2032).
• Low voltage alarm: warns when the car battery is below 11V.
• Supporting function for Toyota: steering angle related matching (used in conjunction with compatible diagnostic tools).
• Supporting function for Lamborghini: ID48 IMMO auxiliary activation (for authorized work with compatible equipment).

In addition, the GT105 II retains its core features: indicators for communication on important pins, the ability to work with separate grounds via PIN4/PIN5, and the function as a 12V power adapter for on-site jobs. For those working with ECUs, diagnostics, and vehicle electronics, it's a tool that often saves time, reduces "guessing," and can prevent problems during voltage-sensitive moments.

Specifications (bullet list)

• Product: Newest GODIAG GT105 II OBD Break Out Box
• Type: OBD2 Break Out Box / ECU Connector / OBD diagnostic & programming adapter
• Voltage display: Shows vehicle voltage directly on the device
• Low voltage alarm: Warning when car battery is below 11V
• CR2032 test: Tests remote control battery CR2032
• Communication indicators: PWM+ (PIN2), CANH (PIN6), CANL (PIN14), K-line (PIN7)
• OBD ground points: PIN4 Body GND, PIN5 Signal GND (separated)
• PIN4/PIN5 mode: Can be switched between shorted and non-shorted
• Outdoor power supply: Draws power from car battery and provides DC12V to external equipment
• DC cable: 0.75 mm² 2-conductor (sheathed cable)
• DC connector: Supports DC 5.5×2.5 / 5.5×2.1
• Protection: Resettable 7A fuse in DC connector
• Connector quality: Pure copper in female connector for repeated insertions/removals and long lifespan
• Battery clamps: Environmentally friendly salt spray-treated, approx. 0.5 mm thickness (according to info)
• Laboratory connection: DC power interface and dedicated laboratory power connector
• Included: 1× GT105 II unit, 1× power cable with battery clamps

Keywords & variations (H2/H3 for SEO and clarity)

The GT105 II can be described as an OBD Break Out Box, OBD2 breakout box, OBD test box, ECU connector, OBD2 power adapter, ECU programming adapter, diagnostic adapter with voltmeter, or OBD battery backup tool. If you are looking for a tool that displays vehicle voltage, helps you see communication status (CAN/K-line/PWM), and can also provide 12V to equipment outdoors – then this is the right category.

OBD2 breakout box for ECU programming

When working with ECU programming or advanced diagnostics, you often want to know if communication is actually getting through, and you want to avoid voltage drops. The GT105 II makes this easier through indicators and voltage display.

OBD battery backup for battery replacement

As an "OBD Battery Replacement Tool," the GT105 II can help maintain power during battery replacement and reduce the risk of settings and data being affected by power outages.

On-site maintenance – power for diagnostic equipment outdoors

The tool can draw power from the car battery and deliver DC12V to diagnostic/programming equipment when you work outdoors, without access to a fixed power source.

Product overview – what the GT105 II does in practice

The GT105 II is used to connect the OBD2 port to diagnostic/programming equipment, while simultaneously providing you with:

• Visual communication status: indicators flash for data on PWM/CAN/K-line.
• Voltage control: voltage display and warning below 11V.
• Flexible grounding: separate PIN4/PIN5 and selectable shorted/non-shorted mode.
• External DC12V: power to equipment via DC connector with fuse.
• Battery replacement support: helps keep the system powered to minimize the effects of power interruptions.

The tool is developed with workshop logic in mind: quick checks, robust connectors, clear indicators, and practical protections (like fuses) to handle everyday connections.

Functions and areas of use

1) Vehicle voltage on display + low voltage alarm

During diagnostics and especially programming, stable voltage is one of the most important factors. The GT105 II has voltage display and can provide an alarm prompt if the car battery drops below 11V. This helps you to:

• Detect voltage drops before they cause problems.
• Determine when you need an external charger/trickle charge.
• Achieve better quality in programming and diagnostic sessions.

2) Communication indicators (PIN2/6/14/7) – see if the car is “talking”

The device has indicators for PWM+ (PIN2), CANH (PIN6), CANL (PIN14), and K-line (PIN7). When data is communicated, the respective light flashes. This makes it easy to:

• Assess whether the diagnostic tool is actually communicating with the car.
• Detect a "silent" bus (e.g., if the connector/pin/adapter is faulty).
• Get quick troubleshooting info without changing tools or guessing.

3) Separate grounds: PIN4 (Body GND) and PIN5 (Signal GND)

In some special cases and programming scenarios, it can be valuable to be able to handle Body Ground and Signal Ground separately. The GT105 II offers independent access to PIN4 and PIN5, which can be helpful for certain modules that require special handling.

4) PIN4/PIN5: switch between shorted and non-shorted

The GT105 II has a function where PIN4 and PIN5 can be switched between short-circuit and non-short-circuit. This is an advanced tool mode that can be relevant in certain workflows and tests. Recommendation: Use this only if you know why you are doing it and are following instructions from your equipment/work process.

5) DC12V power outdoors – power your equipment from the car battery

The GT105 II is designed for outdoor work / on-site maintenance. It draws power from the car battery and can provide DC12V via a DC connector (DC 5.5×2.5 / 5.5×2.1) to diagnostic equipment that needs 12V when working outdoors. The DC connector has a resettable 7A fuse for protection. The cable is specified as 0.75 mm² 2-conductor and the battery clamps have been treated to better withstand environmental influences.

6) CR2032 test for car remote control

The new GT105 II can also test the CR2032 battery in the car's remote control. This is practical when the customer experiences reduced range or intermittent problems with the remote and you want to quickly confirm the battery status.

7) OBD Battery Replacement Tool – power support during battery replacement

During battery replacement, power interruptions can in some cases lead to undesirable side effects. The GT105 II can be used to maintain power and reduce the risk of data/setting loss. According to the product text, it can help to:

• Prevent the clock from changing
• Prevent speakers/audio systems from locking
• Prevent IMMO from locking
• Prevent glass/door functions from needing "resetting"
• Prevent throttle body from needing resetting
• Keep warning lights off
• Prevent fault codes triggered by power interruption

Note: The effect may vary between car models and systems. The purpose is to avoid unnecessary reprogramming and "reset" behaviors that can occur during power outages.

8) Supporting special functions (Toyota / Lamborghini / IMMO tools)

The GT105 II mentions supporting functions for Toyota steering angle matching and Lamborghini ID48 IMMO auxiliary activation. These functions are normally used in conjunction with compatible diagnostic/programming equipment and authorized workflows. We recommend that these functions are only used by professionals with the correct authorization and documented ownership/assignment.

Product build quality – details that make a difference in everyday use

• Pure copper in female connector: supports repeated insertions/removals and long lifespan.
• Standard OBD2 PIN4/PIN5: independent grounds for special programming.
• PIN4/PIN5 toggle mode: shorted/non-shorted for customized scenarios.
• DC cable 0.75 mm²: robust cable for DC power supply.
• DC 5.5×2.5 / 5.5×2.1: compatible with commonly used 12V inputs.
• Resettable 7A fuse: protection in the DC connector.
• Dedicated laboratory connection: DC power interface and lab power connector for workshop environment.

Compatibility – what is the GT105 II suitable for?

The GODIAG GT105 II is designed for use with vehicles that have an OBD2 socket (16-pin) and with diagnostic/programming equipment connected via OBD. It is particularly suitable when you:

• Need visual communication status (CAN/K-line/PWM) during diagnostics.
• Want voltage control and low voltage alarm during sensitive moments.
• Need 12V power for equipment during on-site maintenance without a fixed power source.
• Work with ECU programming where stable power supply and clear communication indication are valuable.
• Want power support during battery replacement to reduce the risk of power outage side effects.

For special functions (e.g., Toyota steering angle matching or IMMO-supporting modes), compatible equipment and correct working methods according to the tool manufacturer are normally required.

Manual / installation guide – complete step-by-step (HTML)

The guide below focuses on safe and legitimate uses: connection, voltage control, power supply, indicators, pin modes, and battery replacement. For any immobilizer/key-related workflows, always follow the instructions from your authorized equipment and work with documented ownership/assignment.

Part 1: Preparations and safety

1. Park safely: gear in P/neutral, parking brake on, good ventilation.
2. Check the car battery: if the battery is very weak, the voltage can drop. The GT105 II warns below 11V – take the warning seriously.
3. Avoid short circuits: keep battery clamps separated and never connect positive/negative incorrectly.
4. Work methodically: always connect according to the steps below and do not pull cables unnecessarily.

Part 2: Connect the GT105 II to the car's OBD2 socket

1. Locate the car's OBD2 socket (16-pin), usually under the dashboard on the driver's side.
2. Insert the GT105 II into the OBD2 socket until it is firmly seated.
3. Turn on the ignition if your diagnostic equipment requires it (e.g., ignition on, engine off) – follow your diagnostic equipment's recommendation.
4. Check that the voltage display is shown and note the value.

Part 3: Check vehicle voltage and low voltage alarm

1. Read the voltage on the GT105 II.
2. If an alarm is displayed (below 11V): discontinue sensitive operations and secure the voltage, e.g., with a trickle charger/stable power supply (depending on the working method).
3. For programming/advanced diagnostics: strive for stable voltage and avoid running voltage-sensitive sessions on a weak battery.

Part 4: Connect diagnostic/programming equipment and read the indicators

1. Connect your diagnostic device/programming unit to the GT105 II according to your setup (OBD cable/adapter).
2. Start communication in your diagnostic equipment.
3. Observe the indicators: PWM+ (PIN2), CANH (PIN6), CANL (PIN14), K-line (PIN7).
4. When there is data communication, the relevant indicator should flash. If nothing flashes: check ignition mode, OBD connector, cable, and that the correct protocol/vehicle is selected in the diagnostic tool.

Part 5: Use DC12V output to power equipment (on-site maintenance)

1. Prepare the power cable with battery clamps (included).
2. Connect the red clamp to positive (+) on the car battery.
3. Connect the black clamp to negative (−) on the car battery.
4. Connect your equipment to the GT105 II's DC output (DC 5.5×2.5 or 5.5×2.1 depending on your device).
5. Check that the device is receiving power. If it does not start: check the connection, cable, and that the fuse has not blown (resettable 7A fuse).
6. Keep an eye on the voltage display during operation. If the voltage drops sharply: pause and secure the battery.

Tip: This method is particularly useful when you need to power diagnostic equipment outdoors or on-site where you do not have 230V available.

Part 6: PIN4/PIN5 – separate grounds and toggle mode (advanced)

1. Identify if your working method requires special handling of PIN4 Body GND and PIN5 Signal GND.
2. Only use the toggle between shorted and non-shorted mode if you have a clear purpose and follow your equipment's instructions.
3. If in doubt: use standard mode and avoid changing PIN modes unnecessarily.

Safety note: Incorrect pin handling can cause communication problems or affect sensitive electronics. Always work with the correct method and good knowledge.

Part 7: CR2032 test (remote control battery)

1. Select/activate CR2032 test mode according to the device's function.
2. Test the remote control battery and note the result.
3. If the battery is weak: replace the CR2032 in the remote control and verify improved function.

Part 8: Battery replacement with power support (OBD Battery Replacement Tool)

1. Plan the battery replacement: ensure you have the correct battery and tools.
2. Connect the GT105 II as instructed for power support (so that the system can maintain power during the replacement).
3. Follow the car's recommended battery replacement procedure.
4. After replacement: check that voltage and system functions are stable.
5. If the car requires registration/coding of a new battery: do this with the correct diagnostic tool according to the car's requirements.

Note: All cars react differently to battery replacement. The goal of power support is to reduce the risk of unwanted side effects of power interruptions.

Part 9: Conclusion and disconnection

1. End diagnostic sessions in your equipment.
2. Unplug DC equipment if connected.
3. Disconnect battery clamps: negative (black) first, positive (red) last.
4. Unplug the GT105 II from the OBD2 socket and store it dry and protected.

Tips & advice – get better results for diagnostics and programming

• Voltage first: If the car is near the low voltage limit, secure the voltage before performing sensitive operations.
• Read the indicators: Flashing CAN/K-line/PWM is a quick "sanity check" for communication.
• Stable power for outdoor jobs: Use the DC12V output when powering equipment on-site, but make sure the car battery can handle it.
• Correct connection: Ensure the OBD connector is fully seated and that cables are not under tension.
• PIN4/PIN5 with caution: Only switch modes when you know why – otherwise, use standard mode.

Frequently Asked Questions (FAQ)

1) What is an OBD Break Out Box?

It's a tool that connects between the car's OBD2 socket and diagnostic equipment to provide a better overview, indicators, and sometimes extra power/pin functions.

2) What's new in GT105 II compared to GT105?

GT105 II is an upgraded version with five new functions: voltage display, CR2032 test, low voltage alarm (<11V), supporting Toyota steering angle matching, and supporting Lamborghini ID48 IMMO auxiliary activation.

3) What indicator lights are there and what do they show?

It has indicators for PWM+ (PIN2), CANH (PIN6), CANL (PIN14), and K-line (PIN7). During data communication, the active indicator flashes.

4) Why is voltage display important?

Voltage drops can cause interrupted sessions and problems during diagnostics/programming. With voltage display and low voltage alarm, you get quick control.

5) What does the low voltage alarm below 11V mean?

It's a warning that the car battery is low. For sensitive operations, you should pause and secure the voltage before continuing.

6) Can GT105 II power other equipment?

Yes, it can draw power from the car battery and deliver DC12V via a DC connector (5.5×2.5 / 5.5×2.1) with a resettable 7A fuse.

7) Is this a “power adapter” for outdoor jobs?

Yes, it is described as suitable for on-site maintenance by drawing 12V from the car battery to equipment when you lack a fixed power source.

8) What are PIN4 and PIN5 on OBD2?

PIN4 is typically “Body GND” and PIN5 “Signal GND”. GT105 II offers independent access to these and can switch mode between short-circuited/not short-circuited.

9) When should I use the switch for PIN4/PIN5?

Only in advanced scenarios where you know why it's required and follow instructions from your diagnostic/programming tool.

10) Can GT105 II help with battery replacement?

Yes, it can be used as an OBD Battery Replacement Tool to maintain power during battery replacement and reduce the risk of data loss and side effects.

11) Does it always prevent problems during battery replacement?

It can reduce the risk, but car models differ. Some cars still require battery registration or resetting after replacement.

12) What is the CR2032 test?

It's a function to test the battery (CR2032) in the car's remote control.

13) Can I use it for Toyota steering angle matching?

The GT105 II has a supporting function for this, but it is used together with compatible equipment and the correct working method.

14) What does Lamborghini ID48 IMMO auxiliary activation mean?

It is a supporting function mentioned in the product text and is normally used in authorized workflows with compatible tools and proper authorization.

15) Is GT105 II the same as a fault code reader?

No, it's a breakout box/adapter. It shows voltage and communication status and can provide power, but the diagnosis itself is done by your diagnostic tool.

16) Does it have a fuse?

Yes, the DC connector has a resettable 7A fuse.

17) Which DC connectors are supported?

It supports DC 5.5×2.5 and DC 5.5×2.1 according to product information.

18) Can I use it in a workshop "on the bench" with an ECU?

The product text mentions that it can be used with a “full protocol ECU programming cable” for studio/lab connection. Such cables may be optional and the working method depends on your setup.

19) Is the ECU full protocol programming line included?

According to the text, the OBD2 full protocol ECU programming line can be purchased separately.

20) What is included in the package?

1× GT105 II unit and 1× power cable with battery clamps.

Package Contents – what's included

• 1 pc × GODIAG GT105 II (host/unit)
• 1 pc × Power cable with battery clamps

Disclaimer & important notes

• Legal Use Only: The tool must be used for legitimate diagnostic, programming, and service work with documented ownership/assignment.
• IMMO/Key Functions: Any immobilizer/key-related functions must only be used by authorized professionals and in accordance with laws and manufacturer guidelines.
• Voltage and Risk: Voltage drops during programming can cause interrupted sessions and, in the worst case, control unit errors. Ensure stable voltage.
• PIN Management: Changing PIN4/PIN5 mode or working with special grounds is advanced. Incorrect handling can cause communication problems or affect electronics.
• Battery Replacement: Power support can reduce side effects, but some vehicles still require battery registration or adaptation procedures after replacement.
• Equipment Dependent: Results and functionality depend on the diagnostic/programming equipment you connect and the vehicle's system support.

Summary – why many choose GT105 II

The GODIAG GT105 II is a well-thought-out OBD2 Break Out Box for those who want to work more controllably with diagnostics and programming: you get voltage display, low voltage alarm, indicators for PWM/CAN/K-line, the option of separate grounds (PIN4/PIN5) and a practical DC12V output to power equipment for on-site jobs. In addition, it can be used as power support during battery replacement to reduce the risk of unwanted side effects from power outages. A strong tool in the workshop – and an even stronger tool when working on-site. ✅

Related on Felkodslasare.se

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