Wiring a Plex dash into M800 CAN

[Richard0990]

HI,

I have a M800 which has a Single Tacho output already wired but not used, I am space limited so want to use a Small dash for my start RPM, and driver alarms, I have looked at a Plex micro dash which would be perfect for the application and space I have available.

This dash has four wires and communicates VIA CAN which is ok, But how would I wire this into the ECU? I have a 5 pin plug in the dash area which is used to make changes to the ECU and looking at the M800 Schematic with pins saying 0Volts and 8Volts and then CAN Hi and Lo, and then Com's I have traced these wires back to the ECU from the UTC-USB connector.

Would I be right in saying I could Tee into a switched positive/Neg (or supply a relay power) to the Dash and the TEE into the can HI and LO that goes to the plug to get the ECU Data? as I cannot see any other outputs for the CAN data other than the Tacho output? Or have I majorly overlooked something here?

Thank you

[Stephen Dean]

Hi,

That is correct, you would splice into the CAN Hi and CAN Lo wires from the M800 and connect them to the Dash, you will need to add a 120ohm resistor across the CAN wires to terminate the bus correctly at that point, unless you want to leave the UTC permanently connected (as it has a built in CAN terminating resistor). The Dash end of the CAN Bus will also need to have a terminating resistor in place, unless the Plex Dash has a built in resistor. The power can be supplied from the ignition switch or relay, just make sure that the wiring and circuit protection as suitable for the extra load.

For configuring the M800 to transmit the correct signals and addresses over CAN, and to have the Plex Dash receive them, you will have to look at the documentation supplied by Plex.

[Richard0990]

Thank you for your reply,

Would it be safe to presume that if I added the resistor to the wiring at that point the UTC-USB connecter would still work?

Thank you

[Stephen Dean]

The UTC will still work.