Hello everyone!

I am new here but I would really appreciate your help.

I have a 08 zx6r, USA version, with PC3 and exhaust, no jumper mode. Everything worked like a charm, I installed the exhaust a month ago and was riding fine with servo motor cables disconnected, but the motor still connected. No FI light came, everything was great. But I decided to solder a DIY servo buddy, the one with LM3900N. So, I installed it and turned the key on but heard the buzzing noise coming from the center of the bike (throttle bodies, pls. see below) and FI light started flashing. I removed the servo buddy and put the servo motor back but FI would still flash and the bike won’t start.

Symptom 1 – multiple error codes. I ran self-diagnosis and the codes are as follows:
11 - Main throttle sensor malfunction, wiring open or short
12 - Inlet air pressure sensor malfunction, wiring open or short
13 - Inlet air temperature sensor malfunction, wiring open or short
14 - Water temperature sensor malfunction, wiring open or short
15 - Atmospheric pressure sensor malfunction, wiring open or short
31 - Vehicle-down sensor malfunction, wiring open or short
32 - Subthrottle sensor malfunction, wiring open or short
34 - Exhaust butterfly valve actuator sensor malfunction, wiring open or short

Symptom 2 – Secondary throttle bodies noise. When I turn the key on I can hear the buzzing noise from the secondary throttle bodies (TBs). I opened the airbox and saw that when the key is turned the secondary TBs start to move and when they are about to fully close they kind of get stuck, move a few millimeters up and down near fully closed position and then stop near fully closed. When I turn the key off they remain in the same position and I remember that when I disassembled the bike previously the TBs were always in half-open position.
I moved the TBs in half-open position manually, as they should be, and turn the key on, but the same happened – they stopped in near fully closed position.

Symptom 3 – Servo motor not working. In addition to this, the servo motor won’t rotate anymore, while previously it worked fine. When I turn the key on it kind of tries to rotate but moves no further as a few millimeters. I’d better say that it shakes a little bit when the key is turned but nothing more than that.

What works. Battery is ok, lights work. Starter works, it rotates when I push the start button, but the bike won’t start.

What doesn’t work. The bike won’t start. Multiple error codes and FI light flashing. Servo motor doesn’t work anymore.

What I checked. I checked the 10amp ECU fuse and the main 30amp fuse under seat and replaced them though they were not blown. Tried to turn the key on without servo motor but it made no difference. Tried to reset the vehicle-down sensor but as I understand it should reset itself once the key is turned off. So I turned the key off for a few times, took off cables from the battery for a few minutes but all the error codes and the noise were still present.

So, I basically don’t know what to do and hope you guys could help.

 

Anyone?

 

Finally received and installed another ECU and the problem was gone! The bike fired right away, no error codes, everything runs great.

I also figured out the problem with the servo motor. It turned out that one tooth inside the motor was broken and was preventing it from turning.