[electroguy]

Hello guys,

Happy Deepawali to all!

I am using the 2015 KTM EXC500 engine (imported from UK) for a Formula Student race car (www.formulastudent.in). I have all the OEM parts in the harness, except the Regulator/rectifier. The wiring diagram supplied by the dealer didn't correctly match the ECU pin configuration, but the color codes are correct. Using that, I completed the wiring. The FI warning light does not show any error code. When I crank the engine, I can see the spark, but the fuel injector does not click. I connected an oscilloscope to the injector pin, there is no pulse.

I used a voltage regulator from Royal enfield 500 EFI. It had a total of 5 wires, 3 go to the alternator and remaining 2 into the battery. But the KTM wiring diagram shows a total of 7 wires, five same as mentioned above, and two more, one of which go to power relay + ECU, and other to light relay. I'm not getting what are these for.

The injector is good and not clogged, I gave 10 volts to it once after removing, and it opened.

I suspect the regulator wire (Black/white) which goes to ECU pin 25. Intuitively this should be ground, in order to trigger the power relay. (Please see the wiring diagrams attached), but maybe some small signal superimposed over it? I have never seen such a setup before. I'm unable to figure out what's wrong. This regulator/rectifier is not available in India, and is around $200. Buying this is not an option, it would kill around one week of time, and a lot of money

maybe you guys could help?

Original wiring diagram (From KTM UK): https://goo.gl/IWbx8w

One page Wiring diagram (Drawn): https://goo.gl/rywncT

All inputs are highly appreciated! Thanks!

- Harshit

[Ameya Janvekar]

Hi

Have you checked the possibility of the local KTMs having a similar R&R?

Also I think that without the ECU + Power Relay being energised, the injectors will not fire. I have come across similar set-up.

Also please see if the ECU has a dedicated power supply line from the battery? This also is a common feature many engines on which I work upon.

Thanks.

[electroguy]

Ameya, thanks for your valuable input. All the KTM's available in India (200 and 390) have the conventional RR setup, which have five wires, three go to stator, one positive, one ground.

The ECU and power relay are both energized. It's there in the wiring diagram. There is no dedicated line to the ECU, all the wires are bundled in the stock harness together.

[ecenandu]

Originally Posted by electroguy

Ameya, thanks for your valuable input. All the KTM's available in India (200 and 390) have the conventional RR setup, which have five wires, three go to stator, one positive, one ground.

The ECU and power relay are both energized. It's there in the wiring diagram. There is no dedicated line to the ECU, all the wires are bundled in the stock harness together.

Did you check whether the roll over sensor is in the correct orientation. In Enfield 500cc EFI, once the vehicle detects roll over, ecu cuts power to fuel injector. The vehicle will only start after a power reset. Please check that.

Keep us posted, when you get the solution. Will be interesting to know the actual cause.

[electroguy]

Originally Posted by ecenandu

Did you check whether the roll over sensor is in the correct orientation. In Enfield 500cc EFI, once the vehicle detects roll over, ecu cuts power to fuel injector. The vehicle will only start after a power reset. Please check that.

Keep us posted, when you get the solution. Will be interesting to know the actual cause.

Yes, the Roll over sensor is in correct orientation. Last year I worked on the the RE 500 EFI engine, and took a lesson from there . I've been stuck on this problem for around 25 days now, and I am trying to contact local KTM service center. Don't know if they would be of much help, because this engine is quite different when compared to KTM 200 and 390.

[ecenandu]

Originally Posted by electroguy

Yes, the Roll over sensor is in correct orientation. Last year I worked on the the RE 500 EFI engine, and took a lesson from there . I've been stuck on this problem for around 25 days now, and I am trying to contact local KTM service center. Don't know if they would be of much help, because this engine is quite different when compared to KTM 200 and 390.

25 days, damn. Anyway some of my suggestion may be trivial but have you made sure that 12V(+) is being supplied to the fuel injector, while cranking?

I think you are using the stock wiring harness and not one made by you guys.

[electroguy]

Originally Posted by ecenandu

25 days, damn. Anyway some of my suggestion may be trivial but have you made sure that 12V(+) is being supplied to the fuel injector, while cranking?

I think you are using the stock wiring harness and not one made by you guys.

I'm using the stock harness. One wire of the injector connector is giving 12 volts with ignition on.

Anyways, I have an update. I was showing the problem to someone in the workshop today, I wired everything up from scratch, and held the injector in my hands, and said, "see, this is not working despite everything is correct", and I cranked the engine. Guess what - I saw a spray of atomized fuel, and I was like, damn . I am still wondering what was actually wrong, my guess would be some loose wiring, but anyways, the injector is now working while cranking. The engine didn't start however, credits to the faulty ignition coil from the old enfield engine. I got very small sparks (2-3 mm) that too reddish blue in color. Will be changing the ignition coil tomorrow. I am really happy today, although I have 2 exams on sunday and I haven't studied this whole semester!

[Ashir]

Originally Posted by electroguy

I'm using the stock harness. One wire of the injector connector is giving 12 volts with ignition on.

Anyways, I have an update. I was showing the problem to someone in the workshop today, I wired everything up from scratch, and held the injector in my hands, and said, "see, this is not working despite everything is correct", and I cranked the engine. Guess what - I saw a spray of atomized fuel, and I was like, damn . I am still wondering what was actually wrong, my guess would be some loose wiring, but anyways, the injector is now working while cranking. The engine didn't start however, credits to the faulty ignition coil from the old enfield engine. I got very small sparks (2-3 mm) that too reddish blue in color. Will be changing the ignition coil tomorrow. I am really happy today, although I have 2 exams on sunday and I haven't studied this whole semester!

Will ask my ex team mates to read up the thread and help. We used the same engine, sponsored to us by KTM. They gave 2 engines and all the electricals and sensors required. Since I was in chassis design, my knowledge in engine domain is weak.

Also, since the issue is fixed, you better concentrate on your exam, and analyse later on.

[electroguy]

So I finally figured out the issue. There is something wrong with the Coolant temperature sensor. As soon as I remove it's connector, the FI warning light comes up, but on cranking, the engine starts. I did this multiple times to confirm this.

Also, there has been a new problem since the engine started. It starts good, runs for 2-3 seconds with a little throttle, but it dies as soon as I give it a bit more throttle. On cranking further, the exhaust is smoky, with unburnt petrol smell (like that in 2 stroke engines in cold). I checked for spark, and I guess that is the issue, because the injector keeps flooding the cylinder, and the spark is not enough to ignite the mixture. On removing the injector plug, and then cranking, the engine runs for 1-2 seconds (again with smoky exhaust), confirming that there is fuel already in the cylinder.

The ignition coil I am using is from CBZ/Hunk. The spark is blue, around 10-12 mm in length, but I am not satisfied with it's sparking frequency, seems a bit slow to me when I compare with other sparks that I have seen. Looks like some problem there. The battery is fully charged so no low voltage issues.

[electroguy]

Hello guys,

first a little background, please read my first post on this thread.

http://www.team-bhp.com/forum/motorb...t-working.html

So now, the injector is working, and the engine starts easily when cold. But it dies instantly on opening the throttle, even marginally. There is burnt oil coming from exhaust. I am attaching a few videos, please ignore the voices in the background (they are random people giving some random suggestions)

https://youtu.be/Qj_ZsHIIzw0

https://youtu.be/2iPFgYgeTaE

What could be wrong? the valve seals are good, since the valve cover is clean, no burnt oil there.

[ecenandu]

Originally Posted by electroguy

What could be wrong? the valve seals are good, since the valve cover is clean, no burnt oil there.

Did you guys solve the problem?

Some fuel injection systems are sensitive to the initial throttle position. Did you guys change the idle throttle position. Certain systems has the ability to adapt to the new idle position but not all systems. The Kehin system which is powering the Royal Enfield 500 is very sensitive, for example.

In the service manual, you can find the relevant information - throttle adaption.

I hope you must have solved the issue by now. Anyway, keep us posted.

[electroguy]

Originally Posted by ecenandu

Did you guys solve the problem?

Some fuel injection systems are sensitive to the initial throttle position. Did you guys change the idle throttle position. Certain systems has the ability to adapt to the new idle position but not all systems. The Kehin system which is powering the Royal Enfield 500 is very sensitive, for example.

In the service manual, you can find the relevant information - throttle adaption.

I hope you must have solved the issue by now. Anyway, keep us posted.

Yes, it's been solved. The engine ran properly for the first time yesterday.

The problem was the ECU which we got with the engine. After trying each and everything possible, we finally concluded that it's the ECU. We borrowed a stock ECU from Team Fateh, Thapar University, as they also have the same engine (Aashir mentioned above), and the engine started immediately on swapping the ECUs!

What you said is correct, the initial TPS voltage should be in the range of 0.6 volts (at idle) to 3.9 volts (at Wide Open Throttle), otherwise the check engine light shows an error.