Hondata

ecu will still run the car but will not connect to the laptop via the usb. also is this chip available for replacement? kpro1

What happens is that the master ground is missing or disconnected or had a high resistance contact to the engine. Or one of the engine grounds is missing. Then if you connect a laptop which is grounded to the car in some way then all the current the ECU sinks travels down the USB cable. This current can be 5 or more amps, which is a lot more than USB can cope with, so something will give. It also has the effect of raising the ground plane in the ECU towards 12V, which then results in a negative voltage from the 5V supply to ground, which makes most electronics very unhappy.
Even if we replaced that chip on the KPro (which we don't) there is a very high chance that other parts on the KPro are damaged. You best option is to replace it.
From customer comments from when this happens it is normally after installing a new engine or rewiring for injectors.

this engine has been in the car for approximately 7 months with no issues. all ground are clean and tight. is there anything else i should look for before i install another kpro? i just want to be sure the same thing doesn't happen when the new unit is installed as they aren't very cheap.

could this be caused by the top of the ecu case coming in contact with the usb port on the kpro? i noticed the case has become dented and is touching metal to metal on the usb port.

Assuming it is an engine swap, look at http://www.hondata.com/techk20swapgrounds.html
Use a multimeter to measure the ground current from the ECU case & USB shield with the engine running to be sure. Anything over about 20 mA is unusual.

ok.. thank you for the quick response. i will give that a shot

ok so im going to get a new kpro4. can i just plug it in and go or does the ecu need to be sent back to hondata since it had kpro1

Assuming that the ECU is not damaged then the new K-Pro board will fit just like the old one.

ok thanks