Are you tired of your ELM327 OBD2 scanner constantly drawing power from your car’s battery, even when your vehicle is turned off? Many car enthusiasts and DIY mechanics utilize ELM327 OBD2 CAN bus scanners for diagnostics and performance monitoring. However, a common issue with these scanners is that they often remain powered on whenever plugged into the OBD2 port, potentially leading to battery drain over time. This article provides a step-by-step guide on how to easily modify your ELM327 OBD2 scanner for switched 12V power, ensuring it only operates when your car is running or in ACC mode.
Why Modify Your ELM327 OBD2 Scanner for Switched Power?
The standard OBD2 port provides constant power ( Pin 16) to connected devices. While convenient for some applications, this constant power supply can be problematic for ELM327 scanners. Leaving your scanner plugged in continuously can result in:
- Battery Drain: Even though the power draw might seem minimal, over days or weeks, it can significantly drain your car battery, especially if you don’t drive your vehicle regularly.
- Reduced Battery Lifespan: Constant discharge, even if shallow, can contribute to a reduced lifespan of your car battery over time.
- Unnecessary Power Consumption: It’s simply inefficient and unnecessary for the scanner to be powered when you are not actively using it.
By modifying your ELM327 scanner to draw power from a switched source (ACC – Accessory or Ignition), you ensure that it only powers on when your car is on or in accessory mode. This eliminates the risk of battery drain and provides peace of mind.
Step-by-Step Guide to Modify Your ELM327 OBD2 Scanner for Switched 12V Power
This modification is straightforward and can be completed in about 15 minutes with basic tools. Here’s how to do it:
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Disassemble the ELM327 Scanner: Locate and remove the four screws holding the scanner casing together. These screws are typically hidden under a label. Carefully peel off the label to access and unscrew them.
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Open the Casing and Disconnect the Connector: Gently separate the two halves of the scanner casing. Inside, you’ll see a small white connector connecting the OBD2 port to the internal circuit board. Carefully unplug this white connector.
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Remove the OBD2 Connector from the Shell: Once the connector is unplugged, you can lift the OBD2 connector assembly completely out of the scanner’s plastic shell. This will give you easy access to the wiring pins.
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Relocate the Power Wire: Identify pin 16 and pin 8 on the OBD2 connector. Pin 16 is the constant 12V power supply, and pin 8 is typically the switched ACC 12V power supply. Carefully move the wire currently connected to pin 16 and insert it into the pin 8 slot. On many ELM327 scanners, pin 16 is located at the top left, and pin 8 is at the bottom left, making this a simple lateral move.
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Reassemble the Scanner: Place the OBD2 connector back into the scanner shell and reconnect the white connector to the circuit board. Carefully align the two halves of the casing and reassemble them using the four screws. Be cautious not to bend the LEDs during reassembly.
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Reapply the Label (Optional): You can reapply the label you removed in step 1 or leave it off, depending on your preference.
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Test Your Modified Scanner: Plug your modified Elm327 Car Obd2 Can Bus Scanner back into your vehicle’s OBD2 port and turn your car’s ignition to ACC or ON. Verify that the scanner powers up correctly. Turn the car off and confirm that the scanner also powers down.
Conclusion
By performing this simple modification, you’ve successfully converted your ELM327 car OBD2 CAN bus scanner to switched power. This ensures that your scanner only draws power when your vehicle is running or in accessory mode, preventing unnecessary battery drain and extending battery life. Enjoy using your ELM327 scanner with added peace of mind, knowing it’s not silently draining your battery when you’re not using it. This modification enhances the usability and longevity of your ELM327 OBD2 scanner, making it an even more valuable tool for car diagnostics and performance monitoring.
