Trickle charger won't light up?
 

I had my alternator replaced last week. The battery was ok, so that wasn't changed.
I hooked up my Porsche trickle charger through the cigarette lighter like I always do, and the top light won't light up? When I push the mode button on the charger the light moves to the car setting, that works, but the top light won't light up. It always started out on orange and then moved to green when the battery was charged. Now nothing on the top light. I checked the cigarette fuse, that's ok. I replaced the fuse in the Porsche trickle charger but the top light will still not light up? Any ideas as to what could be wrong? It has to be something related to the alternator change?

I'm not familiar with a Porsche trickle charger.
Can you try it on another car?
Can you tell if light is incandescent or led? Possible bulb went?

cigarette plugin maintainer
 

Thanks for your reply. I guess I should have called it a battery maintainer by Porsche.
I plug it into the cigarette lighter to keep the battery charged. There is power to the lighter socket, it's a 1999 Base model Boxster.
The maintainer has LED lights.
I did try it on my 2018 Chevy Malibu in the 12 volt socket, (they don't put cigarette lighters in cars anymore) and the top row wouldn't light up on that car either. It may not be equipped to charge through the 12 volt socket like the Porsche.

check fuse in plug tip... if "brains" appear to be working working and you confirmed power at plug, this likely is your culprit.

FYI, they always suggest "plugging" in car first and then charger.

And by sounds of it, you have the Porsche Charge-o-matic II which is a rebranded C-Tek multi 3600 or some such. If you also have the direct connect or "alligator" clips, try those as well to further isolate issue to cig lighter plug.

Good luck :)

If that socket in the Malibu always has power (isn't switched) it ought to work.

Or just test to see if the device is pushing volts... LEDs be damned.

I have the CTEK version of the Porsche battery maintainer. I'm going to guess that the power socket you have your charger plugged into has a GFI outlet somewhere else on the same circuit and the GFI has tripped. I just verified if I unplug my CTEK from power, but leave it plugged into the cigarette lighter in the car, I can cycle the power button on the CTEK through the motorcycle, car, optima battery and snowflake positions. I actually had the same issue as you a few years ago. I thought the CTEK had died and bought another on Amazon, only to have the same issue. I learned there was a basement outlet with a GFI on the same circuit as my garage outlet and it had tripped. I returned the new maintainer and the original one is still going strong for 17 years now!

I have the same problem, what did you do to get the top row of lights to come on?
Also, where did you find that most unusual fuse.

In my case the GFI outlet on the circuit my charger was connected to had tripped, so there was no power at the outlet. If the fuse in the tip of the cigarette lighter adapter has blown, this is how to replace it.

https://www.youtube.com/watch?v=0C8GmV3mPfY

I had no problem accessing the fuse. Finding the fuse is the problem. I had been to Bulbs Plus, Napa, Autozone, Home Depot, Lowes, O'Reilly, ACE, and Fastenal.
http://986forum.com/forums/uploads02...1620172701.jpg

Accessing the fuse is not an issue but finding the fuse is. I only need two just to be safe.
I have been to Batteries Plus, Napa, O'Reillys, Autozone, Home Depot, Lowes, ACE, and Fastenal with no luck.

http://986forum.com/forums/uploads02...1620173317.jpg

Know that in some cases these things just plain die in time...

My C-Tek 3600, referenced above, finally bit dust after 15 years. Connected to one of the vehicles and started charge cycle. Next AM it was smokin' hot! Unplugged and disconnected from vehicle. That lead me to believe might have a bad cell in battery. Tested battery and all good. Checked fuse - fine but changed anyway. Reconnected all and nada - whole thing wouldn't light up - top or bottom row and wasn't putting anything out when checked w my DMM.

Got my $ worth so just ordered a new Battery Tender Jr. kit from one of the warehouse clubs - switched so maintainers for all cars & toys are same platform. Connected maintainer to same vehicle and all 100% again.

Good luck :)