Welcome, Guest. Please Login or Register
MyECU main site
  Welcome to our forum.
  HomeHelpSearchLoginRegister  
 
Page Index Toggle Pages: 1
Send Topic Print
Q6 busted (Read 3509 times)
raz
Senior Member
****
Offline


Guzzi 11OO Sport, My16MkV,
Innovate LC-1

Posts: 373
Stockholm, Sweden
Gender: male
Q6 busted
08/02/13 at 03:54:30
 
Hi

I just repaired a dead My16M, Mk IV or so, and it quickly turned out Q6 was busted. I replaced it and all is fine. What could have caused this (provided it wasn't just a bad component in the first place - it had thousands of kilometers on it though)? What does Q6 do? Is this the one that latches the relay?

raz
Back to top
« Last Edit: 08/02/13 at 03:55:40 by raz »  

59° North
1100 Sport iniezione elettronica -- the perfect merge of a superbike and a steam train
 
IP Logged
 
YaBB Administrator
YaBB Administrator
*****
Offline


I love YaBB!

Posts: 679
The Land of YaBB
Re: Q6 busted
Reply #1 - 08/02/13 at 10:28:47
 
I've seen a few of those failures. It failed with the ECU constantly powered right?

Q6 is the FET that pulls the ECU power relay. Its gate is fed via a voltage divider but I think there is some inductance there that is causing a spike to take out the FET.
On later versions I have added a cap in parallel with the resistor to ground as you can see here.
http://www.cajinnovations.com/MyECU/My16MMkVII/pics/My16M_PCB.png

You should add the cap, 0.1uF, to yours.
Back to top
 

The Administrator.
WWW  
IP Logged
 
raz
Senior Member
****
Offline


Guzzi 11OO Sport, My16MkV,
Innovate LC-1

Posts: 373
Stockholm, Sweden
Gender: male
Re: Q6 busted
Reply #2 - 08/02/13 at 20:14:47
 
If you mean powered regardless of ignition switch, I'm not sure. Running off 9V the boost voltage and 5V were alright but fuel pump did not prime - a little unintuitive to me but I started with checking the FETs so I found it immediately. I'll consider adding the cap. Maybe certain relays are worse, I think mine has internal caps or resistors and that could mitigate the problem too, right? This one failed on a friends bike.
Back to top
« Last Edit: 08/02/13 at 20:20:37 by raz »  

59° North
1100 Sport iniezione elettronica -- the perfect merge of a superbike and a steam train
 
IP Logged
 
YaBB Administrator
YaBB Administrator
*****
Offline


I love YaBB!

Posts: 679
The Land of YaBB
Re: Q6 busted
Reply #3 - 08/03/13 at 08:57:00
 
That sounds like the same failure. It doesn't prime because it does not turn on with the key. Its already on.
Back to top
 

The Administrator.
WWW  
IP Logged
 
Page Index Toggle Pages: 1
Send Topic Print