For car enthusiasts and DIY mechanics, the ELM327 Bluetooth OBD2 scanner is an invaluable tool for vehicle diagnostics. However, many users, especially those working with Ford and Mazda vehicles, encounter a limitation: standard ELM327 scanners often lack support for the MS CAN (Medium Speed Controller Area Network) bus. This guide provides a detailed walkthrough on how to perform an Elm327 Bluetooth Obd2 Scanner Modified Hs Ms upgrade, enabling you to access a broader range of vehicle systems.
Why Modify Your ELM327 Scanner for HS/MS CAN?
Modern vehicles, particularly Ford and Mazda models manufactured from approximately 2003-2004 onwards (such as the Ford New Focus 2006, Mazda 5, and Mazda 6), utilize multiple CAN bus systems for communication between different electronic control units (ECUs). While the HS CAN (High Speed Controller Area Network) bus adheres to the OBD2 standard and is accessible through pins 6 and 14 of the OBD2 port, the MS CAN bus is manufacturer-specific and operates on different pins – specifically pins 3 and 11.
Standard ELM327 Bluetooth OBD2 scanners are designed to communicate primarily via the HS CAN bus on OBD2 standard pins. This means that without modification, these scanners cannot access the MS CAN bus, limiting their diagnostic capabilities on Ford and Mazda vehicles that rely on MS CAN for certain systems like body control, climate control, and advanced driver-assistance systems.
By performing an ELM327 Bluetooth OBD2 scanner modified HS MS upgrade, you are essentially adding the capability to switch between accessing the HS CAN bus (standard OBD2 pins) and the MS CAN bus (manufacturer-specific pins). This modification significantly expands the diagnostic potential of your ELM327 scanner, allowing for more comprehensive scanning and troubleshooting of compatible Ford and Mazda vehicles.
Step-by-Step Guide to Add an HS/MS CAN Switch to Your ELM327 Scanner
This modification involves adding a simple switch to your ELM327 scanner to toggle between HS and MS CAN connections. Here’s a detailed, step-by-step guide:
Parts You Will Need:
- 6-pin Mini-Switch (ON-ON Type): A switch like the MTS-202-A2 is ideal. These are readily available at electronic component stores.
- Connecting Wires: Thin, insulated wires for making internal connections within the scanner.
- Soldering Iron and Solder: For making secure electrical connections.
- Screwdriver: To disassemble your ELM327 scanner.
Modification Process:
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Disassemble the ELM327 Scanner: Carefully peel off the label on your ELM327 scanner to reveal the screws underneath. Unscrew and open the scanner casing. Exercise caution to avoid damaging the internal components.
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Identify a Location for the Mini-Switch: Examine the internal space of your ELM327 scanner to find a suitable location to mount the mini-switch. This may require some ingenuity depending on the compactness of your specific ELM327 model. Ensure the switch is accessible from the outside once the scanner is reassembled.
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Prepare the OBD2 Jack Wires (Pins 6 and 14): Locate pins 6 and 14 on the OBD2 connector inside the ELM327 scanner. These pins are for the HS CAN bus. Unsolder the existing wires connected to pins 6 and 14.
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Connect HS CAN Wires to the Mini-Switch: Solder the wires you just unsoldered from pins 6 and 14 to the two middle pins of your 6-pin mini-switch.
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Connect New Wires from Switch to HS CAN Pins: Solder two new wires from two of the outer pins of the mini-switch to pins 6 and 14 on the OBD2 jack. These will maintain the HS CAN connection when the switch is in one position.
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Connect New Wires from Switch to MS CAN Pins: Solder two more new wires from the remaining two outer pins of the mini-switch to pins 3 and 11 on the OBD2 jack. These will establish the MS CAN connection when the switch is in the other position. Crucially, ensure you correctly identify pins 3 and 11. Pin 3 is CAN High (CAN-H) for MS CAN, and Pin 11 is CAN Low (CAN-L) for MS CAN.
Diagram showing wiring connections for adding an HS/MS CAN switch to an ELM327 OBD2 scanner, highlighting the switch positions for HS CAN (pins 6 & 14) and MS CAN (pins 3 & 11) on the OBD2 connector.
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Test and Reassemble: Before fully reassembling the scanner, carefully check all your solder connections and wiring. It is vital to ensure that CAN-H and CAN-L wires are not mixed up, as this can prevent proper communication. Temporarily connect the scanner to a vehicle (preferably a Ford or Mazda model known to use MS CAN) and test both switch positions to confirm HS and MS CAN functionality. Once verified, carefully reassemble the ELM327 scanner casing.
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Mark Switch Positions: Clearly mark the switch positions on the ELM327 scanner casing to indicate which position corresponds to HS CAN and which corresponds to MS CAN. This will prevent confusion during future use.
Image of a modified ELM327 OBD2 scanner with a toggle switch installed, enabling users to easily select between HS CAN and MS CAN modes for broader vehicle diagnostic coverage.
Conclusion
By successfully completing this ELM327 Bluetooth OBD2 scanner modified HS MS procedure, you have significantly enhanced the capability of your diagnostic tool. You can now access both HS CAN and MS CAN networks in compatible vehicles, unlocking deeper diagnostic insights, especially when working with Ford and Mazda models. Remember to always double-check your wiring and switch positions to ensure correct operation and avoid potential communication issues. This DIY modification provides a cost-effective way to expand your OBD2 scanning horizons.
