[KChappers]

Here is a theory, if the side stand switch or relay was faulty, would this cause the "check" light on the instrument cluster to come on constantly?

 

[XPOH]

if the side stand switch or relay was faulty, would this cause the "check" light on the instrument cluster to come on constantly?

Yes. If they Kill switch, side stand switch, neutral switch (if no lit on gauge cluster) was faulty, than CHEC will be showing on temperature window of gauge cluster.

 

[KChappers]

So I have previously tested the kill switch so I think that is ok, the Neutral light goes on and off when you select a gear so I assume that the GPS is all ok, so the only thing left to check is the side stand switch and relay. Fingers crossed.

I am thinking, in theory I can test the switch from where the relay plugs in (just need to find the correct pins) and I am sure my Haynes manual tells me how to test the relay itself. Shame I cant look until the weekend now because of work :-(

 

[KChappers]

So this weekend findings are:
Tested the clutch switch - all ok
Tested the Kill Switch - all ok
Tested the side stand switch and relay - all ok
Tested the TO sensor - all ok
Tested the ignition - 100ohm ok
Still have a constant "CHEC" on the dash
So I think that it has to be the ECU or problem with the harness.

My problem now is that mine is a UK/euro version so it has an immobiliser, does this mean I cannot just swap the ECU with someone else? is it coded to the bike?

 

[rv6john]

The chip in the key is coded to the ECM from what I understand. I don't know if you can fool it somehow with the key for the ECM you are using.

I'm just guessing, but I suspect that CHEC should not be showing even with the wrong key, etc. I don't think the immobilizer keeps the ECM from powering up (how would it know it has the wrong key if it's dead) it just tells the ECM to not turn on the fuel.

 

[XPOH]

Did you check the side-stand / turn signal relay, located near the fuse box under the driver seat?

 

[KChappers]

yep, all checks out ok. relay is working as it should. I have a slight suspicion that is it a bad ground somewhere so i am going to have to probe everything going back to the ECU.

 

[KChappers]

So I finally persuaded my friend to plug my ECU into their bike and his fuel pump spins into life so I think that my ECU is fine. Back to tracing cables with my new test probe I just ordered lol.

 

[rv6john]

So I finally persuaded my friend to plug my ECU into their bike and his fuel pump spins into life so I think that my ECU is fine. Back to tracing cables with my new test probe I just ordered lol.

At least that is some good news.

 

[XPOH]

Back to tracing cables with my new test probe I just ordered

Good job with testing ECU!
I think you should make sure for good connections in the ECU wire connector that supply a power to ECU. Pay attention to continuity between the ECU pin and power supply wire. If still no fuel pump primes when you turn ignition on and this wire is powered by 12v then this connection is faulty. The ground wire should also be checked in the same way..

Good luck and be patient.

 

[XPOH]

I am talking about ECU pins that are marked by "+" and "-" signs on diagram below.

Also what is this device that is marked by "?" ? Check its continuity also according to this diagram.
This device must provide a connection, as I have drawn in the figure below. If doesn't then this is a reason of your issue.

 

[KChappers]

I think that is the immobiliser??? I have no idea where it is or what it does, my friend seems to think that it is unlikely I actually have one.

Does anyone know where I can find the ECU pin out and voltages for the K5 750? I can find the 1000 but not a lot else.

 

[Chuckster]

This is what the manual says about it:

As far as the immobilizer, the manual I have doesn't show it on the wiring diagram. Frankly, I'd be looking at the big connector between the main harness and front harness. Just test across the connector and see if any of them are open or have a high resistance (anything above a couple Ohms is bad).

 

[XPOH]

Frankly, I'd be looking at the big connector between the main harness and front harness. Just test across the connector and see if any of them are open or have a high resistance (anything above a couple Ohms is bad).

Would the pump primes when this connector has been disconnected, and kill/sidestand/neutral switches are in state of allowing the engine start and the ECU is well powered?

 

[KChappers]

So I still cannot find the issue, however I have found two anomalies-
-Side stand switch is showing open circuit when stand is down but when it is up it is not showing a fully closed circuit it has some resistance still, so I have ordered a spare off ebay to compare and replace.
-Tip over sensor seems to show 0.8v no matter what position it is in, don't know if a previous owner has disabled it or not so i have ordered a replacement to compare/replace anyway.

 

[rv6john]

If it helps, the side stand switch could be causing the CHEC display. (due to no power to the ECM)

You can just jumper the switch to see if that is the issue.

The TOS will not cause the CHEC light, ignore that for the time being.

 

[KChappers]

Just a question, if the bike is in neutral does that not cancel out the side stand switch? Is it not more likely to be a problem with the relay/wiring?

 

[Chuckster]

It should.

Does anyone have a UK owners manual? It should describe the behavior of the immobilizer. I really don't know how to rule it out, but that's a variable we need an answer on. I think it's safe to say the ECM is not booting up.

I'm going to go through this one step at a time like the bike was in my garage. The next task/question will depend on the answer to the first. What I do know is the behavior of the side stand interlock. In neutral, or with the KS up (switch closed), you should get 12V on the O/B wire at the engine stop switch (right handlebar) when the key is on. Do you?

 

[KChappers]

Thanks Chuckster, unfortunately I wont be able to test until tomorrow night, however I assume so as the bike still cranks when the kill switch is on and wont crank when it is switched off.

 

[Chuckster]

I think that's a positive test that the kickstand interlock isn't your issue. It won't energize the starter relay unless the kickstand relay is working. Immobilizer is now the main suspect. However, an easy step is to pull the ECM out (leave it connected) and push each wire, one at a time, into the connectors to make sure the sockets are all fully seated.