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Discussion Starter · #1 ·
Sorry if I am not aloud to post here I've looked for a solutions everywhere and can't find one.

I recently got the error code jg 1.7.7. Which I read it was to do with a dead or dying battery so I replaced the battery with a new but after this code my dash died, i can't see how fast I'm going or how many miles I've done, I've got no tachometer nothing. But if I turn indicator on the light comes on the dash and they work fine, and then if I put high beams on that light comes on and works great. She runs fine (bit slow but it's only a 125馃槀) but theres no dash anyone could shout a few ideas what it might be?! Any help would be appreciated with this as I need it to get to uni and back.
 

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Hi,

What year is your 125? Is it a second-gen with LCD display?
The indicators for turn-signal, natural, high-beam, oil pressure etc are a separate section and not fed through the dash electronics at least on the first-gen bikes.
If it is an older bike you might want to check your stator to see if this is not burned.
 

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Discussion Starter · #3 ·
It's a 2012 duke. Not sure what gen it'll be if I'm honest. I'll check the stator wasn't sure if it was that as It starts up brilliantly but just no dash which has confused me. I got told by my mate to check the regulator which I'm gonna do today.
 

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It is a first-Gen.
Electronics are a bit tricky I found but as the code indicates that the ECU isn't getting enough power, I would check if the stator is okay (roughly the same resistance when measuring wire 1 and 2, 2 and 3 and 1 and 3 then measure wire 1, 2 and 3 to the frame, here in the Ohms setting it should be an open connection on all 3 wires).
If this is all okay, I would buy some electrical contact cleaner/spray take off the large connector at the bottom of the dashboard display as well as the connector on the ECU, spray both sides of each connector (let the stuff evaporate) and re-connect both.
At the same time check if all cables are intact (especially the area where the wire loom goes from the headlight to the frame).
Also, check if all the negative connections are sound and firmly attached.
If all is done and the problem persists you may have a faulty dashboard, regulator/rectifier or something wrong with your ECU.
A last possible solution could be to run the 15 min. reset sequence (search the forum for the procedure and follow it strictly as shortcuts won't work).

Have you measured the charging voltage at the battery when the engine is running at approx 5,000 rpm?
 

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Discussion Starter · #5 ·
My friend tested the battery for me today with some multimeter and its okay and he also checked my stator that was okay to. So on Friday I'm going to get to the wiring loom and all the wire check for corrosion on the wires and connectors. Thanks for the help
 

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Discussion Starter · #6 ·
Today I've checked all the earth wire they were abit rusted so cleaned and got rid of rust. All the connections pulled apart and cleaned with electrical contact spray and ear bud. I then put the bike back together altogether. Then it started fine and dash came on. Went for a little ride worked grand stopped at home. My partner wanted to see so went to show her and nope not working. So I really not sure why it's doing it now.
 

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Well, we now know that the dash IS working, right?
Just need to figure out what wire(s) are faulty/cracked now.
I suspect it must be a negative wire as if it was a signal wire only 1 part of the dash would fail.
Try to locate the negative wire(s) on the dash unit, run a new negative directly to your battery negative to see if this solves the issue.
If so, follow the OEM negative (if possible through the loom) and you most likely find the culprit.
Good luck with your puzzle ;)
 

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Discussion Starter · #9 ·
Today I checked all sire for cracks and splits and they all seem fine I did find a some rust on some of the ground wire connections so I cleaned them up and to no avail still no dash so today I'm going to give the 15 minute reset ago see if that will help. Fingers crossed will let you know if it helps!
 

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Discussion Starter · #10 ·
Well im stumped 馃ぃ. Im gonna try find all the ground connections one more time and see if its that but I doubt it as the fuses are fine. I've tried everything that's been said and still can't find the fault. I'm not to sure what to try now 馃ぃ think I'm going to have to take it to a garage which I didn't want to do cause its gonna cost me an arm and a leg and I've only got a finger 馃ぃ. But thanks for the help when I manage to get it to a garage and if they can sort it I'll post the results on here just incase someone else has the same problem.
 

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I'm pretty sure it must be a wiring issue or at the connectors at the fuse box or the main power relay.
When turning the key, certain functions will be provided with 12V directly such as the dash, fuel pump and ignition.
Other functions will receive 12V after the engine has started.
Have you tried turning the ignition key a couple of times to see if the dash comes on?
Wierd problem but then all electrical issues are.
 

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Discussion Starter · #12 ·
I've acctually had to ride it a few times due to being my only mode of transport. It did turn on when I had stopped once and hasn't worked again since. Everything else works fine fuel pump, cooler fan, light low and high beam and regulator etc. Starts perfect rides grand. Just no display. Ive opened all connections and cleaned them and used electrical contact cleaner but that didn't help. Would it be worth cutting the wiring loom open and following the wires to find the culprit?
 

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The most likely place for wires to get damaged is where the loom goes from frame to the headlamp (right-hand side of the steering head). If you start here (and find something) you do not need to take off the whole loom.


I've acctually had to ride it a few times due to being my only mode of transport. It did turn on when I had stopped once and hasn't worked again since. Everything else works fine fuel pump, cooler fan, light low and high beam and regulator etc. Starts perfect rides grand. Just no display. Ive opened all connections and cleaned them and used electrical contact cleaner but that didn't help. Would it be worth cutting the wiring loom open and following the wires to find the culprit?
 

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Discussion Starter · #15 ·
Right after a couple of days looking and checking wires and corrosion and found the culprit. Just trying to get hold of a soldering iron and a bit of solder and wire to fix it. I did try fix it without but each time I turn to the left it shows the jpg 1.7.7 error and the dash turns off. Postion it to the middle and turns back on. So it is the corroded wire just under the steering block. Once I've fixed it I'll let you know. But thank you for all the help and advise you've given me.
 

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Although a heavily discussed matter, the established tuner community prefers crimping over soldering.
Whichever way, I hope you have solved your issue.
 

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Although a heavily discussed matter, the established tuner community prefers crimping over soldering.
Whichever way, I hope you have solved your issue.
Indeed. Common opinion across experienced automotive electricians and engineers is that inside a cabin of a vehicle is normally ok to solder. Anywhere else which is subject to cable movements such as almost anywhere in a bike loom is that solder cracks because it is rigid but lacks strength. Heat shrink support if you are going to do it but just crimp.
 
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