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Discussion Starter · #1 ·
Been troubleshooting a flashing fi light on my M Project for a couple weeks. Trying anything to avoid taking it to the dealer. (talked to him and he basicaly didn't know any more about the fi system than me). I have a good shop manual. I scored the little switch that sends codes to the lcd (can use a paper clip) on swap meet here. Code showed C29, secondary throttle position sensor. Bought a multi meter and taught myself how to use it (just taking volt and resistance readings). Trouble shot it down to either adjust or replace the sensor. BTW the sensor is the top one on the black plastic module mounted on the right side of the throttle body. That module is the secondary throttle position actuator and the sensor is mounted to that. It reads the position of the secondary butterflies (which is kinda like the choke) and sends that signal to the ecm. Anyway, I adjusted that damn sensor every concievable position and it would not ohm correctly. I had scored a STPA and sensor for a 2001 GSXR off e-bay (rolled the dice and figured what the heck). This afternoon I installed that sensor (it looked identicle to ours) and right away the kohms were with in limits. Spent some time getting it dialed in exact and then put everything (intake snorkle, couple of other sensors, tank and speedo). Buttoned 'er all up, crossed my fingers and fired 'er up.....................
THE S.O.B. WORKS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! No flashing fi light, no codes and sounds oooooooooohhhhhhhhh so nice!!!!!!!!!!!! :lol: :lol: :lol: :lol:
If it weren't for the six inches of snow we got on the ground this afternoon, I'd a ripped that sucker down the street. Well now it's time for some shop clean up and finish up the "nutt'n and bolt'n. I really really want to thank member C50T2006 for all the help. He really walked me through the trouble shooting process and kept me going. His experience with the fi system really helped me out. Thanks man, I owe ya. So glad that monkey is off my back. :lol:
Viper
 

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+1 :applause: :shades:
 

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Hey Viper,
Congrats on your smart detective work, and resourcefulness!

I'm having a similar issue with my C50.
Mine only comes on when it's hot out, but it is happening more frequently.

Two questions:
When you say you adjusted the sensor position, is that supposed to change the ohm reading?-or were you just trying to see if it would help?

I've read a few postings where shielding or repositioning the wiring allegedly would remedy the issue.
My dealer gave me the standard ambiguous answer.
If replacing the sensor would take care of the issue, I wouldn't be opposed to giving that a try.
Thanks,
-Raz

Post note: Stupid thing has been doing this from day one.
I ignored it at first, because I had read on the forum it wasn't a dire issue.
No big deal until you're riding cross country, the fuel light comes on, and you can't check your miles 'cause all the odo says is "FI".
I normally go 170 to 180 on a tankful, but the fuel light will come on anywhere between 120 and 155.
So I don't know if I'm 15 miles away or 60!
 

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Discussion Starter · #10 ·
Raz, has your dealer downloaded the code from the ecm to the lcd display on your speedo? (when you have a fault the code can be displayed where your odometer usually displays). There is a plug behind the right side cover that can be tapped to display the code. This link shows how to do it with a paper clip.
http://www.motorcycle-journal.com/f...secondary-throttle-valve-actuator-defect.html
On mine the code indicated a problem with the secondary throttle position sensor. That will cause the fi light to flash, (it is telling you "there is a problem, download the code and trouble shoot the problem). There are 30+ different codes that will cause the fi light to flash. Mine happeded to be the tps, that dosn't mean that is what is causing your problem. Your right, there have been alot of posts about heat/humidity causing the fi light to flash. I suspect a problem with the wire harness (needs to be repositioned and wraped to insulate it. Do a search for "flashing fi", I think basshole posted somthing about this. Mine involved a tsp sensor that had gone bad. The sensor has internal spring tension and is rotated to establish minimum and maximum ohm readings. The ecm must recieve these readings within certain parameters in order to set the secondary throttle butterflies, I doubt this is you problem. Good luck.
Viper
 

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Are you seeing the 'FI' or 'CHEC' in LCD display? If 'FI' as viper mentioned try and pull code from ECM. If 'chec' then as mentioned it could be a shielding and/or routing problem. I believe there was a service bulletin the dealer should have addressing that problem. A copy was on here somewhere.

Raz said:
Hey Viper,
Congrats on your smart detective work, and resourcefulness!

I'm having a similar issue with my C50.
Mine only comes on when it's hot out, but it is happening more frequently.

Two questions:
When you say you adjusted the sensor position, is that supposed to change the ohm reading?-or were you just trying to see if it would help?

I've read a few postings where shielding or repositioning the wiring allegedly would remedy the issue.
My dealer gave me the standard ambiguous answer.
If replacing the sensor would take care of the issue, I wouldn't be opposed to giving that a try.
Thanks,
-Raz

Post note: Stupid thing has been doing this from day one.
I ignored it at first, because I had read on the forum it wasn't a dire issue.
No big deal until you're riding cross country, the fuel light comes on, and you can't check your miles 'cause all the odo says is "FI".
I normally go 170 to 180 on a tankful, but the fuel light will come on anywhere between 120 and 155.
So I don't know if I'm 15 miles away or 60!
 

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:applause: Congrats, Viper! Truly, You are a groundbreaker here on the VR!
 
G

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Secondary throttle valve actuator

A couple weeks ago my 06 C50T would not stay running cold. No fast idea and I had to keep it throttled until it warmed up. Went home and got the manual out to start troubleshooting. Had a code C28 so that's where i started looking. After some disassembly I found that the secondary throttle valves were not cycling as the manual indicated they should. I followed the testing procedure for continuity, resistance, input and output voltage readings. I started with the throttle position sensor and it checked out ok. Next the secondary throttle position sensor and it checked out ok. Then the secondary throttle valve actuator...no resistance. I found a thread on here that explained how to take it apart and re-solder the connections inside (they are known for getting brittle I guess). Anyway I took it off and did the repair successfully (quite pleased with myself) then broke it putting it back together...BUMMER!!

Ok, you cannot buy that part, you must buy an entire throttle body, new or used, your choice. So, I found one on eBay and it tested out just fine so I put her on. However, it also did not cure the initial problem - valves still did not cycle. Ok, the manual at this point indicated the ECM was bad. I found one of them on eBay and bought it. I've now spent about $250, still less than dealer. The ECM arrived, I plugged it in and guess what...the valves still did not cycle which meant I still did not have fast idle when cold. I retested all the components again (and a few more) and everything passed. Now I am totally baffled! Maybe the ECM I bought is also bad, but the manual gives no procedure to test these. I don't think there is a way.

There ya go, I'm opened to suggestions. My email address is [email protected] if anyone wants to contact me that way also.

Thanks for listening, ah, reading.
 

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A couple weeks ago my 06 C50T would not stay running cold. No fast idea and I had to keep it throttled until it warmed up. Went home and got the manual out to start troubleshooting. Had a code C28 so that's where i started looking. After some disassembly I found that the secondary throttle valves were not cycling as the manual indicated they should. I followed the testing procedure for continuity, resistance, input and output voltage readings. I started with the throttle position sensor and it checked out ok. Next the secondary throttle position sensor and it checked out ok. Then the secondary throttle valve actuator...no resistance. I found a thread on here that explained how to take it apart and re-solder the connections inside (they are known for getting brittle I guess). Anyway I took it off and did the repair successfully (quite pleased with myself) then broke it putting it back together...BUMMER!!

Ok, you cannot buy that part, you must buy an entire throttle body, new or used, your choice. So, I found one on eBay and it tested out just fine so I put her on. However, it also did not cure the initial problem - valves still did not cycle. Ok, the manual at this point indicated the ECM was bad. I found one of them on eBay and bought it. I've now spent about $250, still less than dealer. The ECM arrived, I plugged it in and guess what...the valves still did not cycle which meant I still did not have fast idle when cold. I retested all the components again (and a few more) and everything passed. Now I am totally baffled! Maybe the ECM I bought is also bad, but the manual gives no procedure to test these. I don't think there is a way.

There ya go, I'm opened to suggestions. My email address is [email protected] if anyone wants to contact me that way also.

Thanks for listening, ah, reading.
Will the STV's move by hand when the engine is off?? be gentle and you won't hurt things...
 

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Yes, they move easily.

With the Key off, move them all the way in one direction. Turn the key on. Do they move?

Key off, move them in the opposite direction. Turn the key on... do they move?

If the butterflies are closed when the key is off, they should move to the open position, at up to an 80 degree angle to horizontal. The sensor will determine the position once the engine is running and you will likely find the valves in a partly closed position when the engine is shut off again.
 
G

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According to the manual they are supposed to cycle closed, opened, then around 95% opened. I think the jerk sets them at the 95% but it does not set the fast idle. Hence, it idles too slow for a cold engine.
 

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If they are closed with key off they do open. If they are open with key off they just jerk.
Sounds like they do what they should be doing......

Have you checked the main throttle position sensor adjustment?

you do need the 'dealer' code switch hooked up... It displays in the odometer console.
 
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