Porsche 997: How to Replace Battery

This article applies to the Porsche 997 (2005-2012).

If you're going anywhere in your Porsche 997, then you need some spark to make things happen, and that spark starts with the battery. Okay, fine, the alternator and the rest of the charging system help too, but it all starts, quite literally, with the battery. Heat cycling, age, and use can all make a battery stop working properly. Replacing yours could be a good idea. Here's how to replace a 997 battery.

Step 1 – Open the hood (front)

If your battery is completely dead and your hood is closed, you'll need to have your new battery and a set of jumper cables on hand before you begin. Otherwise, the hood isn't going to open and the battery isn't going to come out unless you are a wizard. If you are a wizard, congratulations. If not, then find your driver's foot well fuse panel and pop it open.

Inside, you should see a red tab with a front hood drawn on it and a yellow fuse grabber. Use the fuse grabber to grab the red tab and pull it out to expose a copper contact patch. Use your jumper cables to connect the red terminal of the battery (positive, +) to the contact patch on the red tab. Connect the black terminal on the battery (negative, -) to your metal door hinge. Now use your key remote to open the hood by pressing the button for two seconds. Voila! Open luggage compartment.

Step 2 – Open the plastic lid over the battery

The plastic lid has two finger-operatable plastic screws, one on either side. Open them up and you should be able to lift the plastic lid to expose the battery like so.

Step 3 – Disconnect the vent hose

Just like emotional humans, your battery needs to vent. Rather than having it do that into the luggage compartment, your battery has a hose that lets it vent to the atmosphere. It's the hose on the passenger side of the battery, or "driver's right" in race car terms. Pull it off with gentle pressure and be careful not to whack your hand on anything.

Step 4 – Unscrew the leads to the battery, negative first

Management training will tell you never to lead with negativity, but we're going to do the exact opposite here. Use your 10mm socket or Porsche tool to remove the black, negative (-) lead from the battery, then the red, positive (+) one. We do it in this order to minimize the chance of grounding your battery to the car's frame which could do nasty things to the electronics. There are a lot of electronics in your car, so it's better to not fry them.

Step 5 – Unscrew the retaining screw

Again on the passenger side, or driver's right in race car terms, there is a screw that holds your battery to the car's frame. Use your 14mm socket or Porsche tool to unscrew it.

Step 6 – Perform a battery-ectomy (by removing it)

All that's left now is to lift the old battery out of its home. But batteries are pretty heavy, especially when they're stuck all the way up under your hood. You may find that attempting to lift your battery out is a humbling lesson in lack of back and shoulder conditioning. For this reason, may people stand in their luggage compartment to lift it out, but be careful. The larger gentleman may cause damage to his car by doing this.

The battery may also take some tilting and wiggling to get it out of its home. Be careful that the terminals don't touch the body of the car during this process, as again, it could cause sparking.

Step 7 – Reverse the above with new battery

Drop that new battery in there, clamp 'er down, connect the vent hose and leads (positive first this time), and you're as good as driving. Well, close. There might be a few little electrical matters to consider.

You're going to need to drive around a little bit, so close your hood. You may be tempted to leave it cracked just in case there's a problem with your new battery so you don't have to use yet another battery to open your now closed and de-powered hood. But if a gust of wind catches your hood and throws it into your windshield, that's going to be very, very bad. Go on and close it.

You'll need to reset your power windows limits. Hold the window switch in the up position for ten seconds. Then hold it in the down position for ten seconds. The window should now know its limits and how to perform within them.

Now let's get rid of some warning lights. Turn the wheel left and right while parked, then drive in a straight line for a short distance. You should see your warning lights go out. If not, drive carefully to a professional.

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