Battery issues...

If I am not driving my 355 within a couple of days, I keep it on a charger. This was on the advice of the previous owner (and others) who recommended regular use of a charger as the car uses quite a bit of juice to power the alarm and ECUs when not in use.

 

There should not be a need to charge the battery for a period of 8 days. The only thing i would be able to tell you is that you may have a ground in your wiring somewhere.. This would cause a constant draw on the battery. These can also be a nightmare to find in any car. I do not know know if there is a typical area in the 355 that people have noticed that insulation wear on wires have caused a ground.. Maybe someone else will be able to chime in and give you some specific places to look.


To find a ground you will need a multi meter, maybe a Fluke brand.. I do not know how much electrical experience you have. You will need to unplug the battery and check the resistance from a wire to the body or ground tab/frame, not a fiberglass body panel... When you get a wire with a resistance of around .1ohm then you have found your ground... Again, in theory one could possibly do this with most of the wires in the car before they find the correct one.. Hence the nightmare....

 

It's possible that the new battery wasn't fully charged when it was installed.

 

you only need 20 watts or less for a trickle charger. And you have the right idea to find the current draw by using the Digital Voltage Meter in current mode to find the leak.

 

Ding Ding

 

untimately it's the battery... but recent generation cars can use a good bit of energy while sitting with the key off... there is a variety of electronics that stay alive / stand by ... drawing energy out of the battery... infrequent use and partial charges from short trips never get the battery fully charged... Ferrari knows that most of their cars are not daily drivers, has noted this and is supplying a charger. Use the charger supplied and you should not have a battery go flat.

...even my imports from "Detroit", have their batteries go flat when unused, I have them hooked up to chargers... it is easier to plug them in if they are not going to be used for a while than letting them go flat...

 

expanding about bit about battery technology... car batteries are designed to supply a pant load of power over a short time ( as in starting ) as opposed to something like a golf cart battery which is designed to supply power over longer period of time

car ( start ) batteries only deliver power for a short time ( minutes ), then crash. The power curves are flat then fall off a cliff... "hero to zero", it's the nature of the beast. That is why one day that battery is good and gone the next. It's the various electronics that keep on using, keeping memories up, door locks, alarm systems, etc even though the key is switched off.

easier to keep the car plugged in

 

I have the same problem. Brand new battery was put in last year and goes dead after about 4 or 5 days if sitting around off the trickle charger. So....I keep my 355 on the charger constantly.

 

My '99 F355 has gone through a couple of batteries. Due to my stupidity. I left the dome light on. Be sure all your accy's are off. It should be able to go at least a month with a healthy Batt. If the problem continues something is draining it. You could if you are a DIY'r disconnect one of the battery leads (on the battery itself) and connect an ammeter in line and see just how much current is leaking. Also you should put a volt meter (multimeter) across the terminals and see that it increases when the engine is running (about 13.8VDC). To verify the alternator is working (hence charging the Batt). You can use the terminals back on the right side in the engine bay.Good luck!

 

Spring for an Optima battery, and forget about it. No trickle charger needed. Plus, if it does go dead after 2 years, they'll replace it for free, no questions asked at Autozone.

Ask me how I know...

 

I have an Optima battery and mine still went dead. I can return it to PEP Boys? It's only about a year old.

 

Optima Batteries are made by Interstate Battery ( www.interstatebatteries.com/ ) , you can check the warranty on their web page, also they have a store locator to find one near you

 

Optima batteries are good batteries, but it is not the brand of battery at issue. Think of a battery as fuel tank, they come in different capacities. Like a fuel tank they will run out, depending at the rate of use and how often it is topped off.

Optima batteries are an AGM ( absorbtive glass mat type of construction, normal batteries are flooded cell, the other type being gel ). AGM and Gel types are sealed, eliminating the need to check fluid levels. AGM are very robust in construction ( technology ) and will stand up longer than the std flooded type. There is a caviat however, the AGM have a different optimum charge voltage making it more difficult to fully charge them with chargers designed for the std flooded cell type. AGM batteries cost about 3 times the std flooded type. When installing an AGM, it would be good update the charging system to match the requirements of the AGM to optimize their designed performance. The same applies to std battery charges, best to use a charger that is designed for the AGM.

 

I recommend to completely switch off electricity using the turning knob in the trunk.

 

It may not be that simple, need to verify what it totally isolates / takes the battery out... it may only shut the engine electronics off ( starting, running ). Security alarms, various locks ( doors etc ) and things that need to keep their memories active generally bypass the isolation switch. It's the electronics that run in the background that drain the battery. The days are gone that all the power is switched off when the key is removed.

 

But....the engine ECU will need to recalibrate as you may know. Which requires all accy's off, idle for at least 15 minutes.

 

I believe the alarm is the only thing drawing current with the kill switch off. And if it's working properly that batt should be good for months.

 

As long as you have the receipt, it shouldn't be an issue. They put my battery on their meter, and it indicated that it was toast, and issued a new battery.

 

I use a Red top and they also have a yellow top battery,
Have used them for years with no issues

 

that's the need to verify... there are factory installed electronics, dealer installed, and other customer installed... as has been mentioned above, need to check how much current is being drawn with everything off... only key switch off, then with isolator off. Ever check the radio power harness, there are 2 power leads, one goes to a switch, the other goes directly to the battery to maintain memory of the various presets.

the condition of the battery needs to be evaluated, batteries get weaker age, start (car) batteries are designed to deliver a lot of power for seconds, a small power drain on a older batttery can "sink" it quickly. There is a difference beween what power a new battery can deliver vs one that has been around for a time. The issue is that power can be consumed with all "off", as long as a drain is there, the batteries will fail with enough time between drives. The problem is not the system, but rather a lack of use to maintain the battery fully charged.

 

+1! It is not recommended to turn off the car using the battery switch as a routine practice. With cars like the 355 you simply lose idle parameters, which can be restored by ideling for 10 minutes with all accessories off and not touching the throttle pedal. With later cars, even more information is lost and techs such as Rifledriver have repeatedly told us to use a battery tender as the superior solution over the battery switch.

 

AGM batteries rock. I currently use a Sears Platinum AGM group 34 in my 355 (they are actually manufactured by Odessey a well known AGM battery manufacturer). It was top rated by Consumer Reports, with 880 cold cranking amps, and a four year free replacement warranty. So far, all of the various battery tenders I own (5 or 6 brands) all claim to be compatible with charging AGM. In fact I have yet to find a battery tender that does not meet the published specs for charging and floating charge rates as spec'd by Optima. Hard to say with Odessey, as they do not publish their recommended charging specs, instead they simply list their recommended brands/models of chargers. It is probably pretty safe to assume most any charger of 10amps or less, that is microprocessor controlled and finishes with a float charge is probably going to be safe to use.

I have used Optima red top batteries in the past and they were quite good. But the past 5 years or so, have shown them to be very fragile when subjected to deep discharge, which of course they are not designed for (I have seen many posts of failures both on this forum and on the FerrariList email list). Were most batteries can sustain a few deep discharges and still be useable (though with less capacity), often times a single deep discharge on a red top will kill it.
If my only option was an Optima, I might be inclined to consider a Yellow top, which is the deep cycle version. It may not have as high a CCA, but will probably last longer and withstand an occasional deep discharge, if that is possible in your application.