Regulator 12v warning output not working

[guzzimeister]

Hi all

 

Have searched the forums and can't find much on this. Just wondered if anyone else has come across this one. After a long run on Sunday, with no issues, I started the bike up again on Monday, and the charge light stayed on with the engine running. I have a voltmeter fitted to the bike which shows the battery charging, also confirmed with a multimeter across the battery terminals. Checking the output from the white regulator lead, compared to earth showed zero volts. Putting 12v on the blue charge light wire which connects to the white reg lead, but for this test disconnected, lights the charge light so no issue here. My guess is the 12v output on the white lead has failed.

 

No big issue cos I have the voltmeter but would appreciate some input into:

- is my guess correct?

- if so, will I damage the battery? Can't see how I could but they are expensive!

 

Have checked all fuses and headlamp relay, headlamp works fine. Regulator has a big brown wire running from its case to the battery negative, having lost a batt and reg in the past.

 

Cheers

 

Guzz

[luhbo]

I can't say much about the possible root cause, but I can say that mine shows the same behaviour when it's wet and water does enter the regulator. The red light comes on, but the 'charging'/voltage regulation is properly working. As the rest of the bike is probably stupid enough to ignore how exactly the flowing Amps were produced, under red light or not, I also just ignore it - having a spare regulator laying around somewhere.

I forgot to mention that I, same as you, also have some sort of a V-meter attached, otherwise I'd certainly be less ignorant.

 

Hubert

[Kiwi_Roy]

Have searched the forums and can't find much on this. Just wondered if anyone else has come across this one. After a long run on Sunday, with no issues, I started the bike up again on Monday, and the charge light stayed on with the engine running. I have a voltmeter fitted to the bike which shows the battery charging, also confirmed with a multimeter across the battery terminals. Checking the output from the white regulator lead, compared to earth showed zero volts.

 

The charge light has +12 Volts on one side and the regulator grounds out the other so if you unplug the dual connector the light must go out.

If youre running LEDs in the dash a little moisture is enough to turn them on but there's really nowhere for the moisture to collect unless it gets in the large multi way connector at the front of the tank, that would be a concern.

 

The charge light is really seperate from the charging function so I wouldn't worry too much, if you need to turn it off you can unplug the dual connector and turn it 90° so only the black wire is connected.

One other thing, have you added a proper ground to the regulator, a short wire from the case to an engine bolt works great and may cure the problem.

[guzzimeister]

Hi Roy,

 

Thanks for this and the wiring diagrams you sent. Why Guzzi (and other manufacturers) can’t do simplified wiring diagrams is beyond me….

 

Had a good look at it today, and swapped the suspect reg with another couple which were an unknown quantity. What was interesting was the effect my temporary earth had on things. I basically just plugged the replacement reg in and earthed it with a jumpstart lead from the reg case to the engine block. Both regs raised battery voltage to just about 13.2 volts at 2500 rpm, with the charge light on one flickering at about 1200 rpm and the other at 1000 rpm. My faulty reg apart from not extinguishing the charge light showed 13.7v at 2500 rpm, so I hoped that a better earth would improve things with one of the others. Incidentally the case on one of the regs was so furry, that even after really grinding the lead jaws into the case it still sparked intermittently, so the earthing arrangement that Guzzi provides (as you pointed out) is just a joke. I earthed the reg case directly via a 30A lead to the battery on the basis of minimising resistance after the last reg blew so this wasn’t too much of a surprise.

 

Anyway, the point of this is that on installing the better of the two replacement regs with a cleaned up case, toothed washers etc, battery voltage was back up to 13.7 @ 2500, and the charge light out at 600rpm. So I learnt two things:

• Charge light doesn’t tell you much except that it is definitely charging. My old reg charged but as you say in your schematic, it looks like an internal resistor blew. I’ve kept it as an emergency anyway

• Earthing makes a huge difference and can’t be stressed enough. Anyone with a Ducati reg should now be removing it, and cleaning it up as per your suggestions. Otherwise it WILL fail.

 

Many many thanks Roy and safe riding.

 

Jon