FI light is on indicates 26 ------- Right knock sensor

My question is I have looked at some post regarding this issue could be a bad ECM or wire leading to knock sensor seems to be the case. To start I put the bike on the center stand started it up and increased RPM's to 4000 for about 10 seconds or so as indicated by the manual, no FI light comes on so this tells me that right knock sensor is good I assume according to the manual.

Next, I warmed bike up till it showed three bars then increased RPM's to 4000 the FI light comes on so could it be the sensor is bad? Bike runs great other than that. Guess its time to pull the right panel off to investigate.

That is great information to know for anyone else that has this problem. Glad you found the problem.

Thanks I was getting frustrated with this dam FI light, had to get to the bottom of the problem.

Russ WIlson said:

Well disregard the above, FI came back on just wanted to make a note. Ordered new knock sensor hope this does the trick or its then replacing the ECM.

Click to expand...

Be aware that there is a fairly well documented service manual error as regards the knock sensors. Assuming you haven't already done so, you might want to read these before you continue :
https://www.st-owners.com/forums/showthread.php?43161-FI-Issues-(Code-25)&p=475607&viewfull=1#post475607
http://stwiki.notonthe.net/twiki/bin/view/ST13/ServiceManualCorrections

This is a good post that details the knock sensor diagnosis, eventual cure, and talks about problems with the service manual:
https://www.st-owners.com/forums/showthread.php?132408-FI-Code-26&highlight=code+26

Hey Mick,

Will check that sub harness, I can see that water could get in between the wire and collect. I talked with a Honda dealer here in Florida and they said it is almost always the ECM but to start with changing out that right knock sensor. What a pain the in the but.


Well contacted Haps Honda today in Sarasota Florida and asked if they had any updates regarding code 26 which indicates bad right knock sensor and he had none. He said if it shows that code it is for the right sensor the manual is correct. He just had a ST1300 in the shop last week with same problem "code 26" and it was the ECM also he stated he has had bikes in that showed code 25 and it was always a bad ECM.

Ended up replacing the ECM $650.00 from Partzilla though I looked for months for a used one to pop up on EBAY with no luck. ECM was the problem though the bike ran fine I just did not like seeing that PFI light on it bugged me.

Wow, well I hope that mine keeps working like it should. Glad you found the problem and fixed it.