Modern Vespa

I have a 2012 GTV that is in semi storage with treated gas and a trickle charger. I went to start it and the battery appeared to be low and would not turn over. I pulled the battery and it appears to be okay but have not taken it in to be tested yet. I cleaned the terminals and reinstalled and everything lights up as normal but when I tried to start it there was a click from the back and everything went dead. 30 A fuse is okay. Could it be a battery problem? Why the click from the back end of the bike? Ant ideas would be appreciate!

Yes, it's the battery. I would bet the voltage drops to about 0 when you put a load on it (the starter).

I should ad that the bike started and ran fine about 4-5 months ago and is stored inside. My first thought was a bad cell in the battery shorting out, but why the click sound? It is a sharp click. The back tire rotates freely.

Definitely the battery. Cheap enough to swap out.

Greetings:

The click is the starter relay. The battery needs load test, may be too weak to spin the starter. You can make sure if you have a good battery and jumper cables.

Okay, the battery checks out okay. So question is is there a resetting circuit breaker in the starter circuit? It seems like when the starter button is engaged there is a short in the circuit that sets off the circuit breaker. After a time the circuit breaker resets. Again I install the battery and turn ignition on and dash lights appear normal. I engage the starter circuit, there is a significant "click" and all lights go out. Nothing! The 30A fuse is okay. I think the issue is in the starter, but did not think there was another circuit protection beyond the 30A fuse. What am I missing?

did you LOAD test the battery? are you engaging 1 or both brake levers prior to hitting the start button? do the brake lights work? How old is the battery? What size is the battery?

Yes, battery was load tested. Brakes do not matter because as soon as the starter is engaged there is a sharp click and EVERYTHING dies. No lights, nothing. Battery is about a year old but kept on a trickle charger and no harsh weather here in Florida. Battery is a YTX-12BS 330 CCA (the GTV takes a different battery than the GTS). I think I'll try a new starter relay because they are pretty cheap. The click I hear is much louder than the typical starter relays I have worked with on other applications. The starter is the only other thing I can think of if there is no auto reset breaker in the circuit. I am open to other ideas!

Battery yup, but also check the connections on the battery terminals for a short or corrosion

Okay, please don't take this the wrong way, but you guys are not listening. I've been working on cars and bikes for over 50 years, I know the normal won't start scenarios. Please read what I have written. This is NOT a bad battery! The only reason I am on here is that I am not overly familiar with Vespa's.

As an aside, how difficult is it to replace the starter relay in the 2012 GTV? How difficult to replace a starter?

are you squeezing the brake lever while trying to start it? if not you need to.

If the relay clicked but the lights stayed on, then it'd be the relay. As the lights go off, there's a large resistance between the battery and the bike. Normally this is a duff battery. However, if that load-tested for >120A then it must be OK. So we're left with a bad connection between the battery and the rest of the bike. This could be in any of the cables and their connectors. Corrosion under a crimp, whatever. I'd first be checking the negative connection to frame. Then the female fuse connections for the 30A fuse.

You said you load tested the battery, but the above you wrote can only be happening if one of the battery cell has reverse polarity..

When you load test the battery what was the voltage reading?

If the click you are hearing is louder than the relay, then it is the actual starter not receiving enough power to actually start the motor..

This is off course a pure guess from this side of the monitor..

But how would these result in no power to anything after I try to start it? I turn the key on and the dash lights come on. I engage the starter and there is a significant click and everything turns off. If I turn the key off and then back on there is NOTHING! No dash lights, no gauge readings. Nothing. I can't see how the things you keep talking about would be relevant. A bad connection would only apply if it was shorting out the circuit because a dirty connection or bad ground would mimic a poor battery. If so, what is the click I hear? I'm guessing it must be in the starter circuit because it can sit there for hours with the ignition on and dash lights functioning.

Voltage: 12.79V
Measured: 330CCA
Rated: YTZ12S

Results: Good Battery
Battery Meets or Exceeds Industry Specifications

So is the 12.79Volt the voltage under load or no load? You need both voltage reading to confirm that the battery is not faulty...

Your numbers above about the measured and rate are irrelevant to the issue..

That looks like a printout from a battery tester like the auto parts stores use. I'll believe the battery is good.

I'd now go back to jimc's suggestion about battery connections and check all of them. Might also measure the voltage at the starter.

I'd also look at the possibility that the starter is jammed somehow and not able to turn, though I would expect a fuse to blow in that case. Jammed starter clutch perhaps. (Bendix or sprag clutch?)

The numbers were from an auto store readout so voltage was under load. I thought about this last night and I keep going back to the battery. (Chorus of "I TOLD YOU SO!") I am going to pull the battery from my GTS300 Super and try it. Hopefully it is the battery because that is easiest to fix. I'll let you know what I find.

It's a bad battery! Tested okay (for what it's worth at the auto parts store) and acted unlike any I have had in the past. Learn something new every day. I'm glad, an easy fix! Thanks everyone for the help!

Did the auto store use a hand-held load tester? If so, those don't actually test for that amount of current, they extrapolate from a high frequency conductance test. No bloody good for starting problems.

Very few places now have the large testers on a trolley. Something like this (a small version!):

https://www.sbsbattery.com/sbs-4815ct-battery-discharger-capacity-tester.html

It had to be a bad cell in the battery because of what you wrote in your first post.

A battery with a dead cell (reversed polarity) does show a nearly normal voltage without load. Your lights in the dashboard only need few mA to work, so the battery had no problem with that. But when you did try to start the engine, then is when you need the full battery capacity (voltage and of course amperage). By not having enough voltage for the starter motor to spin, it did create a short, making the voltage drop below the limit and making even the lights in the dashboard go off (because of the short created by the starter motor).

If you did test the battery under load, as having a meter connected to the battery terminals while cranking the engine, you would have seen the 0 Volts.. Not sure of what test your battery shop did, but the figure you mentioned in your post are simply the battery specs printed on the battery.

Nominal voltage of 12.79, maximum cranking Amp of 330 and a YTZ format for a 12 Amp Hour battery. That's not how you normally get a read out of a battery under load... That's why I was asking for both Voltage figures, as I had the impression that you didn't test the battery under load..

Happy riding...

glad you FINALLY swapped the battery and the scoot started.