Are you sure that the wire you have concluded is the diag wire definitely is the diag wire? Maybe try connecting it to it's own bulb so you're not shorting two circuits together.

I doubt the ECU is at fault, they rarely fail and when they do it's usually down to user error.

100% sure.
I even found the "connector" behind the side panel. Attaching a bulb to it or a multi meter shows no voltage at that connector. Its just 1 wire with bullet style end on it.

I found a yam dealer in Peterborough. It was Webbs but not since October. Will give them a call and see if they can give some insight.

It is with great sadness that I have to put my V-Strom up for sale ☹️
Due to my knee/leg injury I can no longer get on my beloved v-Strom.
I have owned this bike from new (57 reg) DL 1000 in black and Grey 26,000 miles.  I have added quite a few Extras over the years, which are all included in the sale. Heed engine bars, Lomo engine bar bags, Hagon rear shock, Hagon progressive front springs & heavier oil, Big pie Aux unit, Scorpion end cans with removable baffles, Oxford heated grips, Centre stand, Nice sports seat bought from a forum member, Front & Rear cameras ( little screen under the seat complete with Memory card ), TRE bought from a forum member,
Probably forgot some stuff 🤣.
Included in the sale are the Original pipes, the original rear shock ( only on the bike for a short while ), Original seat, oh and to fit the Heed bars on I had to remove the Crash bungs so they will be included with the sale.
I would like £2,600 for this bike I will post some pictures.
This bike is to be viewed in Chelmsford Essex.

Steady away, plenty of time to ease youself into things 

It's coming along 

Just need some opinions on this as I think my ECU is faulty.

The bike does run and work with all lights etc working and so on.

It's just the bike does not rev up to 2k rpm on cold start like it should. It was working intermittently but not any more.

I noticed that the clocks on this bike are not the correct one as they should be white not black. And the white speedo/clocks like on my stolen YBR Custom had a diagnostic light on the right side vs on the black one a right indicator light. Some non custom YBR's do have the same diag light on the black clocks but most just have the indicator light. And to confuse it even more there's a 3rd style of clocks. I suppose I could buy the 3rd style that does have a diag light too but id have to check the wires are the same.

I want to get the white version but they are expensive when they pop up.. The reason for this explanation is to cover what I was trying to do today.

So I thought I could just wire that diag wire to the right indicator light and use it as my diag light. There is a wire in the connector of the loom that does not connect to anything in the connector to the clocks and the wiring diagram confirms this is the wire that would go to that diag light if I had the right clocks for the bike.

But up on trying to get this working I found that I'm not getting a voltage on that wire when turning on the ignition. When the fuel pump primes the diag light is supposed to come on.

I say no voltage, there is but it's wrong. When I turn the ignition on I am getting -0.25 volts. Once the fuel pump stops priming the voltage is 0. When forcing an error by unplugging the fuel pump the voltage starts bouncing around between 0.2v and 1v

From that behaviour I am guessing the ECU is a little faulty. Do you think the same?

A replacement on eBay currently is £40 or more so I don't want to spend that money and have it not fix the issue with the diag light and the bike not reving up when cold. Especially while I am only getting SSP. (Back to work in about 2 weeks)