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If wiring to computer ecu is required would it be easier neater to have like a usb socket type plug on side of computer then you just need a usb cable of any length you need to run the display in your car?

I use mini xlr sockets in my ECUs. They can't just fall out thanks to the lock.

USB just adds More cost and complexity to the design and isn't as robust in a noisy environment at those lengths.

What about those ECUs that have high speed ALDL out of the box like 082, 305 and 424 etc...? Can the LCD tap into the existing ALDL bus in the vehicle?

BennVenn true usb can fall out

Vlad01 good idea and nice and easy to connect if that will work also

Single wire ALDL will be fine so the existing ALDL bus will be fine though I don't think 5v is available from the diag port. You could power it externally and loose the logging function.

Pretty sure there is 5V in the cluster so for those installing them in VN and later cars should have no problems.

Do you know if it's ECU 5v? or just regulated 5v from accessories/ign?

The reason ECU 5v is important is it remains active for around 2 seconds after RPM drops to 0 and the reported battery voltage drops to 0v, this is an ideal signal that the car is off and to commit the log to the SD card, update the file entry etc. There are other ways to do this in software but this seems like the best foolproof solution for logging.

I know on the newer cars with obd2
unit powers up as soon as you plug into car. Even with ignition off. So must get power from the ecu

The 5V in the dash is on with accessories. I don't known enough about the circuitry of the ECUs to know if there is a suitable 5V rail. There is a 5V for the sensors but that is a bad idea to use as it will skew the sensor outputs if you place a load on it. You could always use a 5V reg from the ECU diag port 12V line.

Hey BennVenn any progress on this ?