1200 DVT 2015 Multistrada 1200s Dvt - Fuel Pump Relay Not Operating On Switch On, Why ?

Dear All,
I have a 2015 Multistrada 1200S DVT on the bench with a fault in which the fuel pump relay does not operate on power up but does operate with the starter button pressed.
The fuel pump relay should power the pump on switch on to pressurise the fuel rail but the correct signal (negative / earth) from pin 38 of ECU-A is not being returned to operate the pump relay.
A Motronic 286.4.257.1C Engine Control Unit is fitted which Ducati Coventry (JHP) have no record of, the standard ECU for this bike is 286.4.258.1A .

Questions :-

1. On ignition switch on what device informs the ECU to apply a Negative / Earth to pin 38A to operate the pump relay ?

(Note that with ignition off a 3.4 + volts is present on pump relay pin 2 coming from ECU pin 38A which drops to no condition after a time out period of around 2 minutes).
With the ignition on and the start button depressed this changes to negative / earth which operates the relay to fire up the pump.

2. What Ducati model uses the Motronic 286.4.257.1C ECU ?

Prior to working on any bike I always run the engine and check all functions correctly before disconnecting the battery and commencing work, and all was well at that time but not anymore. Is it possible to corrupt the data within the ECU with a long power outage ? I doubt this very much.

I’ll await your responses before splashing out on a replacement 286.4.257.1C ECU.
Thanking you in anticipation of your replies.

 

Dear All,

Anyone out there with a 2015 to 2017 MS 1200S please try the following and let me know the result :-

1. Side stand down, switch on ignition and check if the fuel pump operates, Yes or No ?

2. Side stand up, switch on the ignition and check if the fuel pump operates, Yes or No ?


Idea is to ascertain if the side stand switch is a safety parameter to disable pump operation if stand down and requires it to be in the up position for the pump to operate.


Thanking you all in anticipation of your replies.

 

Thanks for the reply Glen which leads to a further question.
The side stand switch is a 3 wire affair. pin 3 is to earth, 1 to 6A of the ECU and 2 to 36B of the ECU. With the stand down pins 1 & 3 are looped to put an earth to ECU 6A, side stand up the earth is removed and pins 1 & 2 are looped effectively short circuiting ECU pins 6A & 36B.
Question :- with the side stand down you state the fuel pump still operates, if you press the starter button does the engine start ?
If it does then what the F--- does that side stand switch do for safety ?

 

Well Chris, that begs the question, how on earth did we survive motorcycling prior to the onset of the Health & Safety warriors ruling the World ?

 

If truth be told Chris, I did set off on a BSA B31 in the early '60's with the stand down but never since, one must error to learn.
John Cellier, a good Lad who knows his Ducatis.

 

Aye Freekw.,
In my case the relay does not operate on the initial switch on of the ignition with that keyless wonder but does operate, and hence spin up, the pump when the starter button is depressed, release the button and the pump stops, is yours the same ?
My ECU is a Motronic 286.4.257.1C, what is the number of the ECU on your bike ?

There is a possibility I may have corrupted the Factory set data in the ECU so have sent the unit to Carmo Electronics for testing and possible reset, Carmo located in your country.
Will contact you on the result.

 

To test the fuel pump remove the pump relay (46 in diagram), loop pins 3 and 4 of the harness connector, turn on the ignition and the pump should operate, remove the 3-4 loop and the pump switches off.
If the pump does not operate then there's a fault in either the wiring from pin 4 to the pump or the pump itself.
If the pump operates then the fault lies in either the main relay pin 4 to pump relay pin 1, the pump relay itself or, as in my case, the ECU not providing the -ve. earth to pump pin 2 on the initial switch on.

You can test the connection from ECU pin 38A to pump pin 2 using an ohmmeter, Brown-Black wire, having first disconnected the -ve. connection of the bike's battery, just be careful when applying the meter lead to the female contact of the ECU plug 38A. The numbering goes 1 - 12, 13 - 24, 25 - 36, 37 - 48, you'll need a magnifying glass to make out the numbers.

With the ignition on the Main relay (45 in diagram), operates and applies 12v +ve. to pump relay pin 1 and a -ve. earth from ECU pin 38A (48 in diagram) operates the pump relay.