Join Date: May 2016
Location: Victoria, Australia
2000 ZX12R - Electrical Gremlins (maybe ECU)
I have bought somewhat recently a 2000 ZX12R, stock as they come with 38,000km on it. It currently is experiencing some crazy electronic gremlins. as soon as i bought the bike i found that i had 4 faulty spark plugs, causing a stalling issue at idle or closed throttle when warm.
While riding, it started to "Cut Out" while in higher RPM (felt like a fuel cut). it was not showing any error codes at this point. this issue developed until it finally let go on me and blew the 10A ignition fuse. i refitted the 10A fuse and as soon as i turned the key to the on position it would blow again.
I have replaced the fuel pump as the bike had been sitting for approx 2 years before i got it. After replacing the fuel pump, the issue of the ignition fuse still remained. at some point after the fuel pump was replaced it stopped priming when turning the key to the on position.
If i disconnect all the ignition coils the 10A fuse will not blow, but as soon as i plug all 4 coils in it will blow. as i connect each coil the dash lights will become gradually dimmer, signs of a large current draw?
to rule out a fuel pump relay issue, i swapped the relays between the ecu and the fuel pump. the fuel pump still would not run. I tried earthing out the fuel pump relay and it would trigger the pump to run. i have also checked the continuity of the brown / yellow wire (i think thats the colour, its the fuel pump signal wire from ECU like pin 9 or something) and it checks fine.
After having the key on for 15min or so i noticed that the ECU relay felt warm, so i checked the ECU itself and it was quite hot to touch in one corner. Nearly too hot to comfortably handle.
Has anyone had a similar issue? i am leaning toward an internal fault in the ECU because of the significant heat (the ecu being plastic and not subject to airflow makes me think it is not meant to get warm) and the fuel pump is not being triggered.
Is there a way to test the ECU for faults without purchasing another to swap over? the bike wreckers over here are asking around $250 plus postage for one.