[Duert]

There is a description here on the forum somewhere. I found it while f*cking around with my own immobilizer-issues. Flashing twice could be antenna or key. You can test resistance on the antenna, should be around 17Ohm. Of als je in de buurt van velsen woont kun je de mijne proberen als extra. Switching keys doesn’t do the trick?

Found the procedure, never tried it thoughI don’t have a code card:


procedure to disable immobilizer engine block through throttle twistgrip:

1) Turn the key to ON and fully open throttle. Keep it open. The EOBD
warning light turns off after 8 seconds.

2) Release the throttle as soon as the EOBD warning light turns off.

3) EOBD pilot light will flash. Count a number of flashes corresponding to
the first figure of the code, open full throttle and keep the position for 2
seconds, then release. In this way the input of one figure is acknowledged,
EOBD pilot light comes on and stays on for 4 seconds. Carry out the same
procedure for the following figures of the code. Failure to do so will cause the
EOBD pilot light to flash 20 times, then it will stay on. This means that the
procedure has been aborted. It will be necessary to turn the key to OFF
and restart from point (1).

4) Repeat operations described in point (3) up to the last figure of the code.

5) Release the throttle twistgrip, if the code is correct, the EOBD warning
light shall flash signalling that engine block has been disabled. The warning
light turns off after 4 seconds. If the code is NOT correct, the EOBD
warning light stays on and it is then possible to turn the key to OFF and
repeat the procedure, starting from point (1), as many times as necessary (infinite).

Note: Should the throttle twistgrip be released before the set time, the warning
light turns on again. It is then necessary to bring the key to OFF and restart
the procedure from point (1).

If this still doesn’t work you can consider removing the immobilizer altogether, but you do need to flash the ECU for that. Sounds like a big job, but stelt eigenlijk geen reet voor.

Good luck!

 

[Duert]

Ah ok, no all keys give the same 2 flashes. It sounds you have some experience... Do you have an instruction how to override the key with the electronic code or maybe an instruction how to program the keys again? There a total lack of information about this at the st4s.

There are manuals on how to program new keys. But then it should recognize the red key and be able to start with that one. If it doesn’t, I’m afraid programming new keys isn’t going to help you…

 

[Duert]

Do you have, or have you checked a service manual specifically for the 4s? I have one and also struggled with the immobilizer-chapter, but can’t remember if there is something about entering the code. I can check for you?

otherwise there are not many other options than @bbradsby suggests

 

[Duert]

But it's still no solution to your problem.

Thinking about it: 2 flashes, which should indicate a antenna/chip issue:

• all keys fail to operate, so it's probably not a key(chip) issue (what are the odds that all keys fail at once? very slim).
• The antenna has been replaced by another one, without succes. What are the odds that a replacement antenna is also broken? Slim, but not zero.

Is the antenna correctly mounted? I've read somewhere that the antenna needs to be high enough to read the chip, and mounting it to low is a relatively common issue. Or are there any other materials next to the antenna which can disrupt the signal? Like a flashy aftermarker keycover? When you move the bike a few meters, does it change anything? I'v heard a mechanic once say the overhead powerlines next to a garden disrupted the immobilizer of a bike. You can think of anything.

And last: is the plug/are the pins on the immobilizer clean? No corrosion or moisture?

 

[Duert]

Good luck! Hope this works, because there aren’t any other options I can think of. Maybe someone else has any other suggestions but I’ve run out of mine (other than removing the immobilizer)

You can always ask the dealership for advice, where they will probably replace the antenna and/or immobilizer for a new one (which also will fail over time. The only question is when). Other option is removing the immobilizer and sacrificing this shitty piece of hardware to the dark lord in a fire-infested ritual.

Big question you can ask yourself: how important is the immobilizer to you?

 

[Duert]

Made an apppointment with a specialist who can read her with the right equipment...

For a little bit of expectationsmanagement: although reading the ECU is a good first step in finding a solution, it will probably only tell you the immobilizer is preventing the bike from starting. Not why it’s preventing it from starting.

Your bike has an external immobilizerbox where the keycode is stored. It checks the stored code against the entered code in the key. If good —>’go’ signal to the ECU. If no bueno —> no go. In your case the entered code can’t be verified by the immobilizer. So no bueno, no start.

Question remains: how important is the immobilizer to you? You can try to have a specialist fix it, or consider removing the immobilizer from the ECU and be done with it.

It’s not like there are almost a million pages on different Ducati-sites about failing immobilizers 🙄

 

[Duert]

Is not important at all. I like the bike very much but it is a 2003 st4s...

How can I remove it and start the bike without the immobilizer?

You’ll need to disable the immobilizer in the ECU, which means flashing the ECU.

You can have a shop do it for you, or have a go at it yourself. There is a lot of information on flashing a ECU here on the forum. It’s a relatively cheap and easy fix for a somewhat experienced DIYer.