Help 2018 Nc750 DCT wont start.

[Duncs 44]

Hi all

Need help badly. Working on my NC750 had the fairings off. Put the fairing back on ,forgot to connect left front indicator, I switched ignition on checked indicator flashing fast fast so I did forget. Fairing off plugged indicator in , ignition on nothing , no dash display, no headlight nothing.The only thing on the dash is a flashing hiss and the time when the ignition is off. Checked all fuses including main fuse. Battery voltage 12.88v good. Took the dash out sprayed contact cleaner still nothing. I'm out of ideas, I'm thinking its the ECU blown .   Where is the ECU is it under the fuel tank? If it is the ecu ,then do I need a new hiss set up with keys as well.

[jeremyr62 2,599]

It must be something simple. You can't have damaged the ECU by leaving an indicator disconnected. You are going to have to retrace your steps and check all the electrical connectors. Wriggle everything with the ignition on to see if you get a flicker anywhere.

[Andy m 23,732]

It isn't the ECU, they are close to impossible to destroy. 

 

Work your way backwards, I'd start by unplugging that indicator again. 

 

Andy

[Duncs 44]

I've wriggled everything with the ignition on nothing. Earlier I replaced the 5 amp fuse on the Honda spotlights and got them working. Could it be the ignition barrel being worn out 90k miles on it. Because when you switch the key on nothing changes , only red hiss light and time as when the key is off and/or out.

[Andy m 23,732]

I hope others will chime in about HISS and the immobiliser circuit. IIRC there is a plug down the right side of the faux tank that can give immobiliser gyp. 

 

The ignition barrel is going to have a plug down the cable somewhere. The bike can be hot wired at this point with jumpers in the back of the plug. So long as the key is still in the powered barrel (so the antenna picks up the HISS chip) it should then show more activity. 

 

Good Luck 

 

Andy 

[jeremyr62 2,599]

If it was all working before you messed with it then it is a 99% certainty it is something you have done to it, probably inadvertently. Not much help I know, but you just have to keep at it. On my bike if I use my unchipped, non HISS key, everything turns on as normal but the bike wont start, wont turn over. So I doubt it's immobiliser related, although mine is the later mode*l.

 

* I see the bike in question is in fact similar vintage to mine.

Edited March 13, 2022 by jeremyr62

[outrunner 4,457]

You did not mention what you were doing to the bike that you had to take the fairings off, so perhaps you have unwittingly disturbed something when you were in there so you might need to go back in and check things.

 

 

Andy.

 

[Xactly 5,496]

34 minutes ago, outrunner said:

You did not mention what you were doing to the bike that you had to take the fairings off, so perhaps you have unwittingly disturbed something when you were in there so you might need to go back in and check things.

 

 

Andy.

 

+1 on that. It’s probably a connector that has been disturbed and is no longer making a connection. I assume the kill switch is set to run?

[Duncs 44]

I was changing the air filter and replacing fuse on spotlights. Oil change and filters. Must be a connector left off.

 

[Duncs 44]

Update, I think I have found the problem. There is a connector on the left side of the bike that has 2 wires (one red,one red with black line) coming from ignition barrel to the loom. The red wire was corroded and broken and thus the red black wire provides power when key is off (for hiss display and time) and the red wire provides power to the dash when key is on. I am ready to solder in a patch wire tomorrow morning and hopefully if I am right this will solve the problem.

[jeremyr62 2,599]

A bit disappointing for a 2018 bike all the same. Well done for finding it and reporting it back.

[Duncs 44]

the connector had a clear plastic rubber boot to protect it from the elements. Unfortunately it was pointing downwards so didn't stop dirt and moisture getting in there. Thanks to everyone who suggested ideas here, I kept looking. I was stumped and had no idea how to solve this. Either I fixed it or give up call break down and take it to a mechanic and many pounds lighter. Anyway I am ahead of myself tomorrow will show if we are right.

[davebike 943]

Ah  ST1300 pans do similar  I cut the stupid boots off  they on pand fill up with water and crap !

 

[Duncs 44]

Update. I'm happy to report that my NC is now fully operational. I soldered in a patch wire and she started up first time. My soldering needs lots of improvement so I may revisit said wire and do a better job. Many thanks to everyone here, I think I panicked on Sunday and couldn't see a way forward. You guys helped me focus on the task and got it solved. to this

[bat-kam 110]

well done on finding and fixing the issue. I may have a look at that area on my 2014 model

[Duncs 44]

On 14/03/2022 at 21:22, jeremyr62 said:

A bit disappointing for a 2018 bike all the same. Well done for finding it and reporting it back.

Agreed, but to be fair my bike is a courier bike and has done 90k miles in all seasons and weather from too hot to freezing salted road and the odd day of snow. The main problems that have arisen are fairing fasteners broken, rear shock has failed twice and chains wearing out too quick (520 chains don't last as long as bigger chains like 530). Most bikes these days aren't built to ride these miles and I haven't had any issues with the engine or DCT clutch yet. 

[jeremyr62 2,599]

OK. That explains it. Salt will kill bikes. I use mine in winter but it is used infrequently and it gets washed if used on salted roads.

I'd be fitting a chain oiler if I was doing serious mileage like that.