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Sub Throttle Servo

cannedSardina

cannedSardina

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I am intermittently receiving the code 48 saying the sub throttle servo is not operating properly. From the sounds of it they sound normal when they cycle with the ignition. I pulled air box off to look at them closer and the sub throttle linkage. Could not tell anything is wrong. Cycled the ignition like 50 times to try and get the code to pop up again but couldn't repeat it. The other morning the bike had a dead battery out of the clear blue as well. Maybe from a short?

Does anybody have a video of the secondary flies opening and closing?
Has anybody replaced the servo motor or have any input on the code 48?

Thanks
 
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I've been there. Fortunately, I documented a lot of this stuff.

I tossed questions around in FZ1OA, and the only suggestions were to check wires and/or replace the servo motor. IIRC, the service manual says about the same thing. New ones are likely still made from unobtainium. I found one advertised off of a "perfectly running 08 FZ1" on EBay. It has been working well for me for several years now. The Servo is under the right hand side of the throttle bodies. You can't get to the connections or the motor without pulling the throttle bodies.

I don't have video, but here's what the service manual told me about the diagnostic tests:

Condition: Code 48 is displayed on the instrument panel when the main switch is turned on. The Check Engine Light (CEL) is illuminated.

See the details instructions for diagnostic mode operations on the last page of this document.

Entered the diagnostic mode and selected the sub-throttle servo motor (d56). Turned the kill switch to “run” and the servo motor began to run. As noted in the service manual, you can hear the motor running, and I verified that I could hear it running.

Selected the throttle position sensor (d01) and verified the TPS value from 17 (throttle closed) to 94 (full throttle). Slowly opened the throttle from closes to full, and the value increased through this range with no “skips” or “drop-outs”. The TPS test shows that it is working properly.

The next steps will be to:

drain and remove the fuel tank,

remove the airbox, and

perform the diagnostic test on the sub-throttle valve and throttle body (Page 8-48) to verify that it is operating the flies properly (Page 8-70, Page 7-10).

Performing the “actuate” part of the diagnostic test yielded no response.

Check whether or not the sub-throttle valve is seized (from Page 7-10):

Turn the nut of the worm shaft of the sub-throttle servo motor by hand to check that the sub-throttle valve is moved smoothly by hand.

If it is not moved smoothly, disconnect the link between the valve and servo motor and check whether or not the sub-throttle valve is moved smoothly by hand.

When the sub-throttle valve is not moved smoothly, repair or replace it since the cause it the seizure of sub-throttle valve body itself.

When it moved smoothly at Step (1) and (2), replace the sub-throttle servo motor

Perform the self-diagnosis mode and check the operation of sub-throttle valve by visual inspection (Code No: 56)

The operation should be carried out as:

5-second drive in the full open direction

2-second stop

5-second drive in the full closed direction
 
I have a big write-up on this one as well... it was connected to a big fiasco with my local dealership.

If you think you need to replace, let me know, and I will get you pics and notes. It's not that bad to do, but it's still kind of a PITA.
 
cannedSardina said:
I am intermittently receiving the code 48 saying the sub throttle servo is not operating properly. From the sounds of it they sound normal when they cycle with the ignition. I pulled air box off to look at them closer and the sub throttle linkage. Could not tell anything is wrong. Cycled the ignition like 50 times to try and get the code to pop up again but couldn't repeat it. The other morning the bike had a dead battery out of the clear blue as well. Maybe from a short?

Does anybody have a video of the secondary flies opening and closing?
Has anybody replaced the servo motor or have any input on the code 48?

Thanks
Click to expand...
I have a video but it looks like it must be too big because it stops after loading about 10%. I bought a throttle body off ebay and took the motor off and put it on my existing throttle body and so far is working fine.

The original motor I took out was actually running fine so I put it in the ebay throttle body to see what the issue was. I expected it not not run under load but I could hear it running but not moving the linkage. Upon inspection it looked like the gear on the motor shaft had drifted down and was not engaging the corresponding linkage gear. I tapped the gear down on the motor shaft as far as I could and the put the motor back in the throttle body. It now worked and that is the video I took.

I had similar symptoms that you had in that it came and went but finally was not moving the plates and the error code wouldn't clear.
 
Ok, went through the diag. My tps reading is 16 at idle and 93 at full.

I have the air box off and am watching everything work perfectly and no code. Ran the worm gear all the way both directions by hand. Felt smooth with no hang ups. Linkage appears to be working as should. Taking all that into consideration the intermittentness of this code which does cause the bike to hesitate off idle….I am leaning toward a servo motor that is on its way out? What do you all think?
 
That's possible. Hard to say for sure, I got the code, cleared it and then it came back 50 miles later. It cleared at home, tested ok, then I got the code again on a short ride. The code stayed on when I got home and it failed diagnostics. Replaced the motor and it's been good since.
 
Blue Flash said:
That's possible. Hard to say for sure, I got the code, cleared it and then it came back 50 miles later. It cleared at home, tested ok, then I got the code again on a short ride. The code stayed on when I got home and it failed diagnostics. Replaced the motor and it's been good since
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How exactly did it fail? Maybe I missed something. The linkage was ok and when running that “56” diagnostic test it cycled the servo motor as it should.
 
I don't remember exactly, but it was the test on the cycling of the flies. I think it failed once by opening, chuckling a couple times, and not closing. I don't think it failed the same way every time, but it was in the cycling tests. I have in my notes that it didn't cycle as the manual said, but it doesn't look like I had a lot of detail.

It was always responsive, but it just didn't respond in the correct way.
 
Blue Flash said:
I don't remember exactly, but it was the test on the cycling of the flies. I think it failed once by opening, chuckling a couple times, and not closing. I don't think it failed the same way every time, but it was in the cycling tests. I have in my notes that it didn't cycle as the manual said, but it doesn't look like I had a lot of detail.

It was always responsive, but it just didn't respond in the correct way.
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Ok thanks, you might as well send me what info you said you have. I am likley going to wait for an a new back ordered servo or grab one of those ebay throttle body assemblies.

Thank you for any tips you got.
 
If it's running fine when you have NO codes, that's is like mine was doing. If the code was Present, then it would run strangely and it would fail the tests. The "actuate" test would fail, and the flies wouldn't cycle as the manual described, if they cycled at all. Usually they wouldn't cycle at all if the code was present. If the code cleared, I think they tested ok.

OK. I wrote all of this stuff up to document a total fiasco with the dealer the botched up my valve adjustment. The first ride after the valve adjustment brought me the fault codes. I ended up redoing ALL of the work that they charged me for and refused to make right, so I had to do a lot of editing to remove "color" and pull the info that you likely won't need.

I wrote it all in Word and pared it down and zipped it in hopes that it would all work as an attachment. My apologies for the long-winded explanations... I'm kind of the mad scientist type, and I wrote this stuff up so that I could "remember" what the heck I did!

EDIT: OK, the zipped Word file didn't work. I saved it as a pdf, and that cut the file size down quite a bit. That seems to have worked!
 

Attachments

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As far as parts go, if Partzilla says the part is in stock, it means that one of their partner distributors have it in the computer system as "in-stock". I ordered from them, and I got multiple responses that it was "delayed." When the parts guy I worked with did a search, he said that Partzilla really doesn't know if the parts are in stock, just that somebody's inventory shows in in stock. In my case, and that was 4 years ago, he did a search and determined that there were no servo motors in the USA, only two available in Japan (with a long shipping time). That's why I went Ebay.

If you start getting those kinds of answers, it may be worth giving the distributor a call to see if the part is REALLY in stock. Otherwise, you might be waiting on a unicorn...
 
Blue Flash said:
As far as parts go, if Partzilla says the part is in stock, it means that one of their partner distributors have it in the computer system as "in-stock". I ordered from them, and I got multiple responses that it was "delayed." When the parts guy I worked with did a search, he said that Partzilla really doesn't know if the parts are in stock, just that somebody's inventory shows in in stock. In my case, and that was 4 years ago, he did a search and determined that there were no servo motors in the USA, only two available in Japan (with a long shipping time). That's why I went Ebay.

If you start getting those kinds of answers, it may be worth giving the distributor a call to see if the part is REALLY in stock. Otherwise, you might be waiting on a unicorn...
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Aight, well stock one was like 550$ which I probably would have done bc I just like replacing with new. However, unobtanium for sure. So got the whole throttle body assembly used on Ebay like you all said. Thanks for the recommendation. Will update one I can it installed.
 
When taking the throttle body boots off, I have a set of metric hex key sockets that are a life saver, particularly since I'm a physicist and I'm really OCD when it comes to torque specs on EVERYTHING... hahahaha!

I used those sockets and a lot of ratchet extensions to get to the RB boot clamps. a couple on the right side meant squeezing between the radiator hose and the frame.. I thing the left side clamps were easier to get to. A little bit of masking tape on the socket / extension connections keeps you from having to dig tools out of hard to reach holes.
 
Sorry missed that. I deleted my post cause I figured it out. Have 4mm hex key sockets as well. So I pulled the TB this morning and swapped out with the new to me servo motor that was received on the eBay special TB. Slapped it back together. No codes and started right up. Time will tell though cause it was intermittent before. Some would have probably dealt with it. I decided to just replace it. Try and get a ride in tomorrow, if not than Monday morning commute. Thanks all, I’ll update later.

Good time to DG all the connectors and thoughly clean the throttle body. Hoping for smoother running.

BTW…Blueflash. Your write up was great thanks for providing that. Saved a ton of time.
 
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cannedSardina said:
Sorry missed that. I deleted my post cause I figured it out. Have 4mm hex key sockets as well. So I pulled the TB this morning and swapped out with the new to me servo motor that was received on the eBay special TB. Slapped it back together. No codes and started right up. Time will tell though cause it was intermittent before. Some would have probably dealt with it. I decided to just replace it. Try and get a ride in tomorrow, if not than Monday morning commute. Thanks all, I’ll update later.

Good time to DG all the connectors and thoughly clean the throttle body. Hoping for smoother running.

BTW…Blueflash. Your write up was great thanks for providing that. Saved a ton of time.
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You are quite welcome! I do a lot of this stuff as I disassemble so I can remember how to reassemble.

Then again, it's always good to share. The forums have been priceless to me. Hopefully I can repay by helping other members once in awhile!
 
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