K.Q.

Hi Rennlist-

I recently changed my Interstate battery MTP-94R/H7 that made it about a month after it's 6 year performance warranty.

Note that Interstate online and in their physical catalogs calls for a MTP-49/H8 equivalent. I discovered that despite the recommendation from Interstate, just stick to the MTP-94R/H7. The MTP-49/H8 is too long, and although it fits in the tray, I wasn't able to fasten the bracket to secure the battery.

I have a 2011 997.2 GT3 with Ohlins RT. Following installing the new battery, I discovered the following:
-Front Lift error (was previously coded out for Onlins RT)
-Both Left and Right doors windows will not roll down. They don't move at all for me to reset the parameters per the manual. As well as either side mirrors, and lighting.

I ran my iCarsoft to see the error codes, and I get, "Communication passenger door control unit (comfort)". I also get this message for the driver door control unit.

Have any of you experienced this? First time changing battery during my ownership, and I'm surprised the PCM doesn't store the coding for the front lift, as well as both of my doors are not communicating?

I've disconnected the battery to try to "reset", but no luck. I'm assuming I need to have front lift coded again, and get the door messages cleared/enable door communication?

Appreciate any help here.

Thanks,

Kyle

bweSteve

weird. I have literally pulled my battery out & put back in at least a half dozen times a year, for the past 3 years (many reasons, so lets not get into that).

I do not have a iCarsoft, nor Durametric or any other, so I will not be of much help. But I am certainly interested in how or why this is happening.

K.Q.

Yeah, I was only expecting to reset window parameters like the manual states. Or as I researched, some don't need to do anything after changing the battery like yourself. Is your car coded with anything?

runet

Check fuses.

gerryros

Same - I put in a new battery last month, just swapped it out myself. I did have some lights come on and stay lit at first start up (PSM failure, maybe ABS too and one or two others) which I read somewhere is to be expected, but just shut the car off and next time I started it all was normal and has been since.

JB911

It should have reset itself after starting and driving. I have the longer/full size battery, Bosch AGM. I've posted about it, had to have a friend weld a nut to the bottom of the tray. The hole is there, but it needed the nut.
I've also described the problem with the pin where the positive cable attaches to the firewall. There's a red clip that you pull to release it, then pull the cable out. I use scotch brite to clean the pin, then spray Deoxit(or other corrosion inhibitor)to both the pin and the female side of the positive battery cable.
There are some horrific corrosion examples on the 997 group, and some have converted from this quick release pin to the replacement threaded pin with nut and washer. That involves going inside the car and is quite a pain to do. Keeping it clean and protected from corrosion is a must. I also sprayed ceramic coating in that area of the firewall in an attempt to keep the water beading and not going in there when I wash the car.

And as part of what I consider maintenance, I've gone under the car, removed all the cables at the starter and ground strap, cleaned them with scotch brite or fine sand paper, sprayed Deoxit, and retightened all the connections.
I had the "clicking starter syndrome" that so many people get. Never replaced the starter, it was just a matter of making sure contacts are clean and tightened. And it's been a few years since I posted that thread(3 or 4 years?)
So many people just had their starters replaced when all it needed was cleaning and tightening.
I live in a swamp(South Florida)and humidity is the problem. A new battery is always good, but that pin needs to be cleaned and protected. Not saying that's your problem, just a warning that over the years it can get severe.

Best,
JB

K.Q.

Fuses all good.

bweSteve

I don't really know what that question means. It's all stock with low miles. No one has changed any code settings with a PIWIS or Durametrics, or anything like that

JB911

I've looked through PIWIS for battery settings on my car and haven't found which control unit/module it might be under. I thought it would be under Gateway or Vehicle Electrical but I couldn't find it. I just started learning to use it, did a VAL and Vehicle Handover log and everything is ok after fixing my dead control-valve next to the disc valve on the transmission. That was months ago, I gave up on Durametric since it detected nothing.
So one of the first things I wanted to do is see if I could make sure the car is set to AGM. Got rid of the wet battery years ago since water evaporated so easily, was too small, and who wants acid spills...
I'll try to do a scan this afternoon and see where would one choose battery type. Other models certainly have the option, maybe 997s/GT3s don't. I might code comfort windows, to open and close through the remote/key while I'm at it-

JB

Igooz

OP, try and hold down the open or close button for 5-10 sec. and see if that helps resume window operations. Similar routine was required on my MB (yes, different car) after a battery change were I totally disconnected the battery without providing power during the swap.

FWIW: I have owned 5 997 GT cars and the longest for 13 years and have always swapped the OEM lead/acid for Interstate AGM. Windows always worked afterwards, but I have had lots of other dash lights that eventually cleared.

K.Q.

I was referring to any aftermarket coding. Front lift coded out, PASM from aftermarket coilovers. You're all stock and no code changes as you note.

Yeah, wasn't expecting any of this.

Update: I called Porsche Dealer today and they told me I need to register the battery to the car. I asked are you sure? On a 997.2? They called back and said you were right, you don't need to. They said they need to plug in and troubleshoot, but they're booked out for a month.

Taking to a local reputable indy Porsche shop this week to see. They think they need to establish communication to the doors again.

JB911

I looked through all control modules on PIWIS last night and on my 997.2 there's no way to code battery type

JB

K.Q.

Update: Took the car into AR Motorsports to see if they could resolve. They hooked up 2 different tools that were reading that I had multiple module communication errors to the doors, but couldn't connect to resolve. They recommended I disconnect the battery overnight to try a system reset. (Previously, I only removed battery for like 15 mins).

Magically, when I reinstalled the battery, all communication to the doors was established, (windows, locks, mirrors, interior lights all work now). Also my front lift coding is back, so no more messages there either.

Thanks to the team at AR Motorsports for their time and expertise.

Bxstr

Thanks for the info. Should help someone out in the future.

HawkerDriver

Do y’all have the interstate battery
model number that works for a 997.2 GT3?

im getting quotes from the dealer of $1200 🥸