Ducati.ms - The Ultimate Ducati Forum banner

2005 ST3 Check engine light

8668 Views 13 Replies 10 Participants Last post by  couchflyer
When I turn the key to on and the bike goes through it's self test, the yellow check engine light (EOBD) stays on and the engine is disabled. I do not hear the fuel injection whir and the bike will not turn over.
I have over 6,000 miles on it and this has happened twice. Once after 3 months at 3,200 miles and once at 5,300 miles.
The first time I thought the battery was low, so I put it on a battery tender for an hour and it started right up. Lucky I was home.
The second time I had just rode 150 miles on the freeway, stopped to get gas and it did the same thing. After about 15 times of turning the bike off and on it started and I was able to complete a 1,200 mile trip. It hasn't happened since.
I added a volt meter after the first time to see the battery voltage and it showed 12.6 VDC during the second occurance.

Has this happened to anyone? Are there any suggestions on what to look at next?
Thanks
1 - 14 of 14 Posts
Check all you connections.. I had the same problem with my 748s. I replaced my pump and same problem.. It was a small connector under the front faring. So talk to local dealer and see if they can show you where all the connections might be for the ST..
Have you read the section of the manual regarding overriding the lockout using the throttle grip to enter your electronic code?
Oilyduc said:
When I turn the key to on and the bike goes through it's self test, the yellow check engine light (EOBD) stays on and the engine is disabled. I do not hear the fuel injection whir and the bike will not turn over.
I have over 6,000 miles on it and this has happened twice. Once after 3 months at 3,200 miles and once at 5,300 miles.
The first time I thought the battery was low, so I put it on a battery tender for an hour and it started right up. Lucky I was home.
The second time I had just rode 150 miles on the freeway, stopped to get gas and it did the same thing. After about 15 times of turning the bike off and on it started and I was able to complete a 1,200 mile trip. It hasn't happened since.
I added a volt meter after the first time to see the battery voltage and it showed 12.6 VDC during the second occurance.

Has this happened to anyone? Are there any suggestions on what to look at next?
Thanks
Yes. I had this happen to my ST4S on and off several times. According to what the manual says this could happen if the immobilizer can not read the ignition key, the EOBD light will stay on. It would take two or three retries and the engine would start ok. I did switch to the extra key and the problem has lessen some but no totally.
It still could be a loose connection or problems elsewhere but my dealer didn't offer any solutions, only if it happen more often that he would have to investigate closer.
Same - same as extrapilot. I have an 04 ST3 which I ride to work and I would say that I have experienced this about 8-10 times in a year. If I switch off and then back on it always starts second go. At first I thought it was happening when I leave the key in (off) while i roll it out of the garage, but this is not the case. I have a battery condition lite and the problem is not associated with voltage. I think the immobilizer just fails to read the key.
Check engine light-update

I had a good conversation with the service department and they strongly recommend using the key to turn the bike off, not the kill switch. They did lean pretty heavily toward the immobilizer circuitry and the key not synchronizing.
I pick up the bike from the 6,000 mile service tomorrow and they will let me know if any faults showed up on the system.
Thanks for the input.
Check engine light update

The dealer did not find any faults in the ECU at the 6K service.
The bike runs better than new and is very smooth and progressive.
It's a little too cool to ride a lot now, but it seems to be doing great.
Thanks for the input.
My bike does this occasionally, and I have no red key or code card! I really need to fix that.
If you turn on the ignition and wait too long before hitting the starter (15 seconds?), the immmobilizer will kick in.

If the yellow check engine light is on, there should be an error code registered which can be displayed on the speedometer if you follow the right procedure to bring it up. I forget the procedure, but someone here is bound to know it and have the list of error codes.
Bill_Anderson said:
...I forget the procedure, but someone here is bound to know it and have the list of error codes.
Prodedure to show error code on my '06 ST3s is to hold the A button on display unit and turn key on. It shows the error code after a couple seconds - if it finds more then one error it will cycle through the codes.

On my bike codes starting with Er37.x pertain to the immobilizer.

Where X is:
.0 = Key Missing
.1 = Antenna Disconnected
.2 = Something wrong with display panel
.3 = Serial Cable Disconnected
.5 = Key Not Recognized
.6 = Immobilizer Memory Blank

I haven't experienced that problem yet....
See less See more
I've never had a problem with the immobilizer. i never use the kill switch to shut down the bike.
rallystar

Where did you find the codes? My ST-3 is giving me 37.3 & 38.0

Thanks
couchflyer said:
rallystar

Where did you find the codes? My ST-3 is giving me 37.3 & 38.0

Thanks
I have the service manual for the '06

In my manual - again it is an '06

37.3 = Imobilizer Error - Serial Line Disconnected
38.0 = CAN Line Error

The CAN line is the same thing as the serial line - so somewhere I'd say you have a cable unplugged. there is an imobilizer antenna that is way up underneath the black cover where you put your key in. The cable has a connector just behind the head stock above the airbox - I'd start with that.
It turns out my ground on the ECU is bad, actually it wasn't connected. If your having starting/running problems check the ECU ground.
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top