3Series

I'm trying to arm chair diagnose my "no start" condition.

Car is a 2009 997.2 C2S with 30k miles.
Current battery is a Interstate Megatron Plus battery. (no idea how old it is)

• Current Voltage on the battery is 10.96
• I've been trickle charging it since last night with no meaningful change in the voltage. I get readings from 10.96 to 11.30.

1.) I couldn't jump start the car last night using my wife's SUV, the battery was a lot smaller and I had it hooked up for maybe 5min before attempting to start the Porsche. The good part is that the radio came back alive and the windows started to work again but the car woudn't start. (2014 MDX with a ton of plastic covering everything. Dumb design for accessing the battery, I had to pull two large pieces of plastic off which could be a real nightmare when its 10 degrees outside. (Side note, my jumper cables are really cheap and thin)

2.) When I try to start the car, I can hear clicking so I think the starter is ok.

2.) I think the battery is just toast. Thoughts?

JasonKM

sounds to me like the battery is toast. What caused it to die off? Did you leave something on or did just go. If it just went then I would tend to just change it. If you left something on then get a real charger and charge it and have it load tested at the autoparts store.

If it was me, for the price of a new battery I would simply replace it and be done with it. Walmart has a well priced 94R / H7 battery and so does Costco

JW911

If it won't take a charge then yes it is toast. Just replace it and you should be fine. If you don't drive frequently or keep it on a charger, these cars eat batteries.

semicycler

How to read the Interstate battery date code: http://www.interstatebatteries.com/m...age-of-battery

BIG smoke

-Does the MDX not have a positive post in the engine compartment. Check your owners manual.
-Life it too short for crappy jumper cables. They could have been crappy enough not to get enough juice to your dead car.
-Decode you battery date with the above decoder ring. Get a new battery. Not worth pissing around for $150 bucks.

Blu311

I have heard this but I was surprised to see when I checked my battery that it is still on the original Porsche battery with a date in late 2008 - my car was sold new in January 2009. Car has been driven regularly and has 65,000 miles that have been fairly evenly distributed over the past 6.5 years.

I plan to buy my new battery at Costco, and here is why:

• P-dealer wants $200+ for battery
• Costco wants $89 and it comes with 3 year full replacement warranty
• I just had my battery in my DD giving me problems at 30 months and Costco replaced free of charge without even checking it, and then gave me a no-cost 36 month full replacement warranty without charging me a cent!

The only 'problem' with Costco is that they wont remove/install the battery for you so either bring a tool, bring battery in another car, or make two trips to avoid the core charge.

3Series

I took a pic of the battery cover last night, but of course Interstate wouldn't put the date code on the top, it's too logical! When I was taking the pic I was thinking 50/50 this probably isn't the right spot. Because while the car is at home I wanted to figure it out at work.

I'm planning to pick up a new battery tonight, thanks for the Costco tip, I didn't even think of that, I was going to go to Walmart for the $150 battery. (just called my closet Costco and they don't have H7)

What befuddles me is why the car wouldn't start with a jump?

I don't think I left anything on in the car, I think the battery just died. The car is 6 yrs old and the interstate is obviously not the original battery. The car was originally from Arizona, so maybe the heat there kills batteries early.

3Series

Not that I could see. I was looking for it as I'm familiar with them on BMW since the battery is in the trunk. On the MDX the battery is right up front but under some sort of plastic intake held on with two plastic rivets and friction held with some huge rubber connector at the other end. I truly think the engineers thought "just release the two rivets and detach the intake to get to the battery". It is sort of simple but typically when your battery dies most people are already stressed and don't need the extra hassle of taking off plastic bits. Also, I had to use a screw driver to open the rivets.

Blu311

Crappy jumper cables may not be getting enough juice to a dead car, I've had this problem with another car a while back and learned not to buy cheap cables.

Yes, Arizona summers are more brutal on batteries than Ohio winters, I can attest to that first hand.

Quadcammer

10.96 is dead, dead, dead.

Replace battery

mjsporsche

I assume most of you know that when you park your car in your secure garage at home, you should lock the doors as it shuts down all the electronics that continue to operate if you leave the doors unlocked.

I used to keep the doors unlocked, with a trickle charger and did not realize that electronic drain continues with the doors unlocked.

OKB

its dead, it wont charge up. buy anything that fits like interstate, sears, advance auto, napa, what ever is the best deal, they mostly have same specs

JW911

I don't know why this happens. But I can attest to this being normal when the battery you are jumping has truly dead cells that can never be revived. Back in the day I owned quite a few clunker cars and had this experience many times.

3Series

Battery was dead dead dead.

I replaced the Interstate Battery with a Walmart Evermaxx and it fired right up.

Right now I can't recall if I locked the car doors but at the least the car is hooked up to my trickle charger right now.

Also, FWIW, the Interstate battery had a date code of 12/2011.

Astur

Bought my mint 997.2 with only 15,300 miles back in May and battery died after two weeks. Tried to revive it with slow charge but to no avail.

So I bit the bullet, went to the local Pep Boys and bought a Bosch battery for $198 with a $20 rebate from Bosch that helped alleviate the local 11.5% sales tax. BTW, it has a 72 month FULL rebate and the sales manager was kind enough to allow me to take it home without having to leave a core deposit.

Interesting enough the battery that I was replacing was an Interstate!