Looking for advice (random electrics issues)

[Baph]

OK, K6S, erm, a *few* electrical mods (but nothing recently added/removed/changed)... Apologies for the long post...

Right, as some will of read, my clocks looked like they kept resetting. Whilst riding down the road, the clocks themselves would just shut-down. This lasted a split second, when they appeared to reset themselves (like they do when you turn the ignition on) - only when doing this, they also lost time functions & reverted back to 00:00.

That went on for a while, and then the LCD panel, rev counter, red & yellow warning lights decided they weren't going to play, and we're going to take their ball home with them!

After some fettling with a multimeter, I decided the best option was to be new clocks.

New clocks fitted (from an unknown age donor bike - but it had a black frame, so K5+), and initially, with just the ignition on (no engine, and bike stationary), they were reading perfectly fine, 0mph.

So I bolted the bike back together, and just before it was complete, I decided to test the clocks. They now thought that because I'd attached the bikini fairing, I was doing 140mph (again, the bike was stationary at this point!!). Hitting the kill switch made it realise the error of it's ways, and it went to 0mph. Flip the kill switch back, and 140mph!

So more fettling with a multimeter, and I worked out that the speed could be affected by the position of the loom feeding the clocks (specifically near the clocks connector), and managed to get it reading 0mph again.

Out I go for a test ride. Hmm, the bike is faster than I remember. Sh!t have I really been doing 60mph in this 30mph zone when my speedo wasn't working? No, the speedo is reading wrong. 30mph reads approx 90mph on the clocks, 90+ (private runway) reads as being 186mph. I can't get it to go above 186mph, so I'm thinking that's an ECU limitation.

Today, after the Barmouth run, I noticed something odd. If I park up for any length of time (literally, 5mins is enough), with the ignition off, and the key out, the bike thinks it's doing 5500RPM. :confused: Turn the ignition on, and it'll redline (engine not on) for a second, then drop back to 0, at which point the LCD fires up, idiot lights come on, and I can start the engine as normal.

Whenever I turn the ignition off, the time resets to 01:00 (is the SV clever enough to auto adjust for DST?).

I haven't really tested the speedo pickup properly, but I did disconnect the sensor from the loom, and it still gave me the same results as above (inaccurate readings for speed). To me, that indicates the fault isn't there.

Now then, the options that could cause this (to my thinking):
- Wiring loom faults (eg, clocks connector primarily), I plan to replace part of the loom when possible,
- Charging circuit fault (leaving power to the bike when ignition is off - only way to explain the rev counter IMO) - reg/rec recently replaced, alternator output is fine, battery checked fine.
- ECU fubar'd - I plan to 'borrow' one for testing purposes from a K4N.
- Incompatible clocks for my ECU/speedo pickup.

So, anyone any ideas? I've put the ECU into dealer service mode, and it comes up (unsurprisingly) as c00 - no fault found. :(

[Jamiebridges123]

I'd hazzard a guess and say that it's just a wiring fault. I doubt that it's a charging fault. What 'electrical mods' were done..? :P

Take it to a 'zuki dealer and ask them to have a look if you're at a lost cause. :(

[Baph]

I'd hazzard a guess and say that it's just a wiring fault. I doubt that it's a charging fault. What 'electrical mods' were done..? :P

Take it to a 'zuki dealer and ask them to have a look if you're at a lost cause. :(

The only electrical mods that are still on the bike are:
- Aftermarket electromagnetic horns - wired with a relay on the horn button circuit, and powered from battery positive. Ground is supplied from the bolt holding the rear fairing on (front right of the rear fairing, vertical bolt through to the frame).
- Aftermarket airhorns - wired in a similar fashion to the above, only the relay coil on this is triggered by the electromagnetic horn relay.
- Oxford Maximiser charge cradle - wired direct to both battery terminals.

All the above electrical mods were on the bike a long time before issues occurred.

In the past, I've had a few other things on there, most of which unfortunately contractual obligations prevent me going into detail about. However, everything that's been wired for that sort of thing has been as per the alarm (now removed - again, removed a long time prior to issues arising).

The alarm:
Positive taken from battery, ground on same bolt as previous. Ignition sense into the spare slot next to orange wire in the back of the fuse box (shares the same fuse), output to both indicators at the rear.

The bike has aftermarket rear indicators (but these couldn't possibly cause the issues experienced, as they're bulbs (23w 12v) & simply utilise stock wiring). Front indicators are stock.

If it is a wiring fault, I suspect the only place it can really be is the connector to the back of the clocks, as this is the only common part in terms of rev counter/speedo/fuel light/time functions. However, that connector wouldn't explain the rev counter at 5500RPM when the ignition circuit is off, as that connector shouldn't be supplied with 12v in that state.

Possibly that points to a faulty ignition barrel. There may be multiple failures, but I highly doubt they'd all strike at the same time.

My plan to attack it so far:
- Substitute ECU for one from a K4N, which is known to be working & good. If this resolves issues, then new ECU required, and the bank manager will love me long time!! :(
- Replace front loom (connectors from behind headstock to the clocks/headlights)
- Re-check charging circuit.
- Beg/borrow/steal some K6 clocks to test with.

I'm not quite at the point of taking it to a dealership. :)

[Jamiebridges123]

Try disconnecting the wiring loom going into the clocks to see if it still displays the 5500rpm.. then try disconnecting the battery and seeing what happens, etc. That should either point to a wiring/clock issue or a charging issue or something.

[Baph]

Try disconnecting the wiring loom going into the clocks to see if it still displays the 5500rpm.. then try disconnecting the battery and seeing what happens, etc. That should either point to a wiring/clock issue or a charging issue or something.

Erm, sorry, have you seen the loom that connects to the back of the clocks?

Disconnect it, and it will quite obviously zero the rev counter. As there'll be nothing at all plugged into it. There's only the one connector. :confused:

Also, with the battery removed, and the engine off, there's no source of power. The rev needle is operated by resistance, if you don't push any current through it, it will naturally rest at zero RPM due to the spring on the back of the needle (just the same as if you pull the plug out of the back).

If I disconnect the battery with the engine running, the engine won't stay running for long due to it being a fuel injection bike not a carbed bike.

Further, the rev needle only shows a static 5500RPM when ignition is off, something is powering the rev needle without the ignition being on, removing the source of the power won't really help identify the component that's messing the system up.

[Jamiebridges123]

Ah, I was just generalising. :razz:

I see what you are saying now. :) When the bike is off (the ignition anyway) it rests at 5500? You said that whenever you turn the ignition off the bike resets the clock.. I'm guessing it could mean something wrong with the charging system? You also said that doing about 30mph would register as 60? and 90+ would register as 186? Could the clocks themselves be faulty/incompatible? Or some sort of calibration? I'm just guessing ideas here. :D

[Baph]

Ah, I was just generalising. :razz:

I see what you are saying now. :) When the bike is off (the ignition anyway) it rests at 5500? You said that whenever you turn the ignition off the bike resets the clock.. I'm guessing it could mean something wrong with the charging system? You also said that doing about 30mph would register as 60? and 90+ would register as 186? Could the clocks themselves be faulty/incompatible? Or some sort of calibration? I'm just guessing ideas here. :D

For purposes of clarity. :)

When the ignition is off, and has been for any length of time (5 mins will do), the RPM needle rests at 5500RPM. When the ignition is turned back on, the rev needle climbs to the redline, then falls to 0, then the clocks power up as usual. There on in, the rev needle works correctly, but the time on the dash reverts back to 1am.

The clocks resetting was a fault on my previous clocks - which have now been replaced.

TBH, I think that the clocks display a speed value dependant on what the ECU converts the speedo sensor values to (I don't see the point in making clocks intelligent enough to work out those conversions when the ECU will have that data - not on a budget bike anyway). This makes me lean towards possibly faulty ECU (and I'm going to swap it for the ECU from a friends K4N when I get the chance).

An interesting test will be when the rev needle is resting at 5500RPM, without turning the ignition on, remove the ECU. I suspect the rev counter will drop to 0, pushing me further into thinking the ECU is at fault.

I think the inaccurate speedo issue is the loom that comes from behind the headstock & feeds the headlights/clocks. Playing with the connector on the back of the clocks affects the speed reading when the bike is stationary (even when the speedo sensor isn't plugged in!!). This may of even caused the ECU to develop a fault, which is why this will be replaced before I try my friends ECU - to minimise the risk of damage to his ECU.

[flymo]

Sounds like a fried ECU Baph.

[Baph]

Sounds like a fried ECU Baph.

Agreed, thankfully eBay has quite a few that are a lot more reasonable than OEM prices (are they having a giraffe wanting that much!!).

I just don't want to fork out that much money until I'm sure, so I'm going to swap ECU's for a known working one first.

If I'm honest, I think my multi-meter fettling earlier (pointy clocks diagnosis thread) has killed the ECU by connecting pins that I shouldn't of. Bit of a bugger, but that's life. :)