temperature sensor - grounding? (short fake) - ducati.org forum | the home for ducati owners and enthusiasts

Remember me
Login  |   Register

ducati.org forum | the home for ducati owners and enthusiasts > Superbike Model Specific > 999/749

Reply
 
LinkBack Thread Tools Display Modes
Old June 18th, 2019, 06:46 PM   #1
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
temperature sensor - grounding? (short fake)

Ok, I've moved on to a small problem that everything points to as being the culprit. Namely, the air temperature sensor.
The previous owner had mention that it needed to be replaced because the temperature reading on the dash was always wrong, and the initialization procedure to check for error codes revealed the following: "air temperature sensor shorted to power supply" (error EF1 4.1).
So, I've already ordered a new sensor, but my question here is; is there a grounding wire somewhere that I should find and check? I looked at a manual, and tracing the wires shows them leading to the dash. I'm going to go ahead and pull up the schematic to see if I can find where it would get its grounding from, but I thought I might try this board. It appears to be a common problem.
Thanks.
Fancyboy is offline   Reply With Quote
Remove Ads
Old June 18th, 2019, 08:10 PM   #2
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
By the way, does that really have an effect on the EFI system? Its common knowledge that O2 sensors are something FI systems rely on, but has Ducati taken a different path by incorporating ambient air temperatures in place of o2 exhaust sensors?

Curious.
Fancyboy is offline   Reply With Quote
Old June 19th, 2019, 10:43 AM   #3
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
I spoke to a couple of tech guys today on that last question, and I thought I would post it here for the benefit of others.
Both of them indicated that the air temperature sensor does have 'some' effect on the fuel-air mixture. They also seemed to confirm one another that it wasn't as critical a measurement as other factors, but a factor nonetheless.
I'm curious to see if there will be any noticeable effect once that is fixed.

On a side note, the schematics didn't indicate any direct grounding of the sensor. Since its going through the dash, it is obviously dependent on a ground that is shared, so logic would dictate that if that were a problem, it would affect other components too.
Fancyboy is offline   Reply With Quote
Old June 19th, 2019, 11:15 AM   #4
Member

ducatis in the registry:
[999 S]

 
Join Date: Aug 2014
Posts: 88
The ambient temp sensor is located on the RH side of the headlight housing in a black rubber boot.

jusutus is offline   Reply With Quote
Old June 19th, 2019, 11:42 AM   #5
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
Thanks for that. I was looking around to see if I can access that without having to remove the upper fairing, and it looks like I can get to it by removing a black plastic cover underneath (above the front fender), secured by 3 or 4 cap screws.
Fancyboy is offline   Reply With Quote
Old June 21st, 2019, 07:19 PM   #6
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
Well, I replaced the sensor, but Im still getting the amber "check engine" light, and the air temperature reading on the dash still shows no value. Just a couple of dashes instead of a temperature.
I checked the continuity at the pigtail, and even hooked the contacts to the switch using jumper wires to eliminate the possibility that the connections were not making contact. I also checked for voltage at the pigtail, and it is getting 5 volts.

I have to say, it isn't making any sense. It seems like the ECU is not processing the voltage for some reason. The error code says that the sensor is "shorted to power supply", so I don't think it has anything to do with the black ground circuit. The fact that I got a voltage reading at the contacts would indicate the ground is fine, would it not?

Even with that, the bike seems to run great, but I cant help but think that it could run better. Afterall, the EFI is supposed to be factoring in that reading for the fuel air mixture adjustments. The problem must be in the ECU.

Last edited by Fancyboy; June 21st, 2019 at 07:46 PM.
Fancyboy is offline   Reply With Quote
Old June 21st, 2019, 07:26 PM   #7
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
To clarify, I checked for continuity between the wires and their respective pigtail contacts, but I didn't bother to check for continuity between the two contacts because that would only tell me what the error code has already indicated. It seems to be a ECU issue.
Fancyboy is offline   Reply With Quote
Old August 2nd, 2019, 09:54 AM   #8
Junior Member

No ducatis in the registry

 
Fancyboy's Avatar
 
Join Date: Jun 2019
Location: northern California
Posts: 11
I have to make a correction to one of my posts. It turns out I was reading my multimeter wrong. I'm actually getting no power (signal from ECU) at the sensor.

I had taken the bike to the dealership to diagnose the problem, and after sending them a couple of pdf files to illustrate the wiring diagram for them (!?), they decided that they couldn't dig too deep into it because they were busy for summer.
Anyway, I may have found the problem, but in trying to replace a circuit, I damaged the tiny connectors, both at the sensor and at the dashes harness connector. So instead, I decided to replace the front harness, and will be receiving that in the mail today.

If this doesn't fix the problem, and the engine light persists, Im considering resetting the ECU connection to the dash. I do have a red key, but I am wondering if this would affect the performance flash that was done to my ECU to accommodate the performance exhaust? I guess my question should be; does "resetting" it using the red key actually reflash the ECU? I would think it would not.

On that note, what exactly is the procedure using the red key? I know the manual shows how to code new keys using that red key, but I don't think it mentions how to reset the communication--or does it?

Thanks.
Fancyboy is offline   Reply With Quote
Reply

Thread Tools
Display Modes


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -7. The time now is 07:02 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
SEO by vBSEO ©2011, Crawlability, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.