Stupid questions, but are the connections good (not corroded or bent - both those on the battery and in both ends of the plug if you have a pigtail on the battery)? Is the fuse good? There is an in-line fuse on these, I believe (or am I thinking of the NOCO ones - I have both).

 

No fair question, this was one thing that was highly recommended from most posts i ran into. The car is up on a lift so ill have to go check.
My thought was if it was fine for the last 2 months not being driven then why now?

but ill find a way up there

 

is the new battery a maintenace free or identical to the stock battery? My 2015 4C came from factory with a wet cell battery requiring water top offs. My new battery in 2021 from dealership is maintenance free. i am assuming the battery is a standard type battery. The Ctek we have is not for other types such as lightweight race batteries.

My manual says that the red light can be caused by:
-the positive lead NOT connected fo the + terminal. Check the connections!! (I have seen some members that didn't realize which posts were positive and negative or had them backwards)
-Battery is sulphated and needs to be replaced. Yours is pretty new so probablly not the issue.
-May not maintain a charge so battery bad. Probably not the issue
-HAS THE CHARGING STOPPED IN STEP 1 OR STEP 4.... DISCONNECT AND RECONNECT TO RESTART..

 

I honestly don't know if it is a maintenance free battery or not. I got the exact replacement from alfa and would have to look up that part number.

I have left the charger on this car for 6+ years i feel its safe to assume that its not the connection but will look

My only thought is its the charger itself?? I will try another charger to see if that one is upset and report back

 

I had a new CTEK charger go out after a year. Got it replaced under warranty.

I boxed my factory charger up and have been using a CTEK model that can also charge AGM batteries and has the de-sulfation option.

 

Ok gents I am familiar with these OEM 4c chargers since I also have had issues a few months back. I have been using this same tender for 7 years trouble free in cold NE winters and on my 2nd battery. In Oct I noticed the tender started to appear to be working indicated by the lights then after a day it would reset itself and start the cycle over again. Now mine never thru a red light which is typically a connection issue as it would have indicated this immediately upon connecting I'm betting its the tender. I looked for a fuse and reset all connections and the same. I ended up getting a Ctek off Amazon which folks here recommended and no issues after replacing. I should have listened to my wife which I never really do and just replaced it due to age.😂🤣. Hopefully she won't do the same with me. I did buy 2 of these OEM tenders but decided to keep original one since they are impossible to find anymore. The Ctek is actually a nicer tender. If anyone knows where the fuse is please let me know on these OEM tenders. I don't see an inline fuse and was going to take the tender apart over the summer.

Here is what i got and it is actually on sale now.

CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V https://a.co/d/i3Vsp4v

Optional:
CTEK (56-915) Black Bumper https://www.amazon.com/dp/B0722GXNJR?ref=ppx_pop_mob_ap_share

 

In regards to the tender fuse it appears to be on the quick connect cable positive side towards the battery. So it is inline. So in my situation it was not the fuse but the tender as I did not change the quick connect side of the battery since this Ctek has the same plug.

 

I have a bunch of CTEK chargers... The 4C version, the Lithium version, and a couple of others... About 3 months ago I had the same issue with the Lithium version on the 4C. The reason I use the CTEK is the quick connects and extension cables that you can use. I had the battery quick connect on the 4C for 5 or 6 years and the silly rubber stopper doesn't always stay in when it is not on the charger. The end result is that the pins in the battery quick connect were corroded. I did my best to clean them but that fix would only last a week or two. SO, all I did was buy a replacement extension cord and battery terminal and it has been working perfect for the past 2 months.

So as the other said... try a different battery connector. I think the 4C version came with the battery alligator clamps, so if you want to try that first prior to buying to ensure it isn't the charger that will also work. (I did this to ensure that everything else was OKAY during diagnostics.)

 

All of you guys are great. I got a lot of very helpful ideas before Jeff Bezos could get me a replacement charger in less than 10 hours!!! You guys are way faster than him!

So the answer was a bad charger. New one came in, went right to stage 4 and appears to be happy. So for those in any other similar situation be aware, chargers go bad. Interestingly enough the factory CTEK charger for my 5 year old Mclaren went bad this winter as well. In the spring I will replace the actual connections to the car.

Question, I keep the negative end of the charger to the negative end of the battery. Is that okay or ideally do I want that on a stray piece of metal?

So, I have read many questionable things regarding CTEK chargers, a lot of people all over seem to be unhappy with them and I'm now in that camp. When one of these goes out NOCO seems to be the favorite out there and is cheaper.

Again, thank you for the help and a simple answer is always my favorite!! Enjoy the ass end of the alfa and the poop shoots of a mclaren from above

 

All of you guys are great. I got a lot of very helpful ideas before Jeff Bezos could get me a replacement charger in less than 10 hours!!! You guys are way faster than him!

So the answer was a bad charger. New one came in, went right to stage 4 and appears to be happy. So for those in any other similar situation be aware, chargers go bad. Interestingly enough the factory CTEK charger for my 5 year old Mclaren went bad this winter as well. In the spring I will replace the actual connections to the car.

Question, I keep the negative end of the charger to the negative end of the battery. Is that okay or ideally do I want that on a stray piece of metal?

So, I have read many questionable things regarding CTEK chargers, a lot of people all over seem to be unhappy with them and I'm now in that camp. When one of these goes out NOCO seems to be the favorite out there and is cheaper.

Again, thank you for the help and a simple answer is always my favorite!! Enjoy the ass end of the alfa and the poop shoots of a mclaren from above View attachment 164695

Been using mine for nine years this coming March. Happy with C-Tek….I have upgraded to an AGM but still use the original purchased for my Sud and 147.

 

Just want to chime in for all of you in the cold northern climates. I have all diff brands tenders/chargers but be warned that the Noco ones shut off at -20 Celsius (-4 F). I guess the reasoning in that batteries shouldn‘t be charged at temps below. Pretty useless to me as other tenders don’t have this feature. Store both my 4c and Spider in a separate dry cold garage. My 2015 4c is still on its original battery with no issues (yet lol)

 

Good to know. I’ve not had mine shut off for temps, but even if it’s below -20 outside perhaps it’s still enough above inside that they were spared turning off.

 

Trade secret: The battery for a Dodge Dart fits and has more cranking power than the Alfa dealer item.
Iput one in my 2015 in 2022 and saved $$$ by going to the Dodge dealer.

 

Note: one of the the plastic covers of a clamps of my CTEK charger flew off never to be seen again, I don't use the clamps anymore!!!