batteries

If it fails that test, it is obviously bad. There is also a load test which is much better and can be done by any battery shop and the battery doesn't even have to be in the car (be sure you have the radio code, you'll need it after reinstalling a battery). However, suppose the battery turns out to be fine. They won't be able to test the charging circuitry without the car if that turns out to be necessary.

You can also buy a battery and alternator tester for around $30 (Actron CP7611) but it is just a sophisticated voltmeter.

Better testers put a load on the battery and see how it responds. They are much more accurate than the simple voltage test outlined above. The Actron CP7612 (100 Amps) is a lower priced model, the CP7614 (130 Amps) will put a larger load on the battery.

A cheaper one is here.

More information on testing a battery can be found here.

Your battery is fine when jump started and charges fine

but discharges quickly with the key is turned off and removed?

disraeli posted this on www.ppbb.com

"The factory technical manual (Section 97-07 page 2) has the following table of total electrical load after the car has been shut off (ModelYear 02):

(electrical current is worst case, i.e. car loaded w/all options...)

FROM TO mA

0 min 5 min up to approx. 950

6 min 15 min up to approx. 900

16 min 20 min up to approx. 750

21 min 60 min up to approx. 50

61 min until the battery is empty up to approx. 30

1000mA equals, of course, one amp.

If the car had no options whatsoever, the load after 60 min would be 17mA instead of 30mA.

From this table you should be able to insert an amp-meter between the battery and battery cable and tell if the car is within spec before you begin pulling fuses or removing the battery to get it tested."

And once you see the draw is beyond spec, you pull one fuse at a time noting if the current draw drops within spec when the fuse is removed. Find the one that causes the excess draw and you have located the circuit that is causing your problem.

Richard Hamilton provided this:

A useful tool for monitoring batty condition over time is a Ancel Battery Minitor. Bluetooth, allows monitoring batty voltage via an app on your phone.

Changing the battery is easy

First look for the radio validation code. Just in case.

Use a battery maintainer or 12 volt battery (or even a 9-volt) connected through the lighter socket or onto the special posts within the fuse panel (see instructions above the fuse panel cover) to maintain voltage when you remove the old battery. Maintaining power allows the computer to hold the memory for things like your radio station presets, electric window stops, on-board computer settings, ECU data, the radio security code for early Boxster years, etc. It is more a matter of saving time by not having to reset everything. Disconnect the car from power for more than 30 seconds and you lose these memories and you have to reset the options, reset the radio code, the car has to spend an hour learning its engine settings, and the dealer may have to be visited to reset some options.

Remove the cover from the battery.

Remove the cable clamps from the battery posts.

Climb into the trunk.

Disconnect the vent tube.

Lift the 40 pound battery out.

Clean the cable clamps so they make good contact.

Look at the battery tray and see if it needs cleaning/painting.

Lift the new battery into the trunk and climb in again.

Install the battery on top of the battery tray.

Secure the new battery.

Connect the vent tube.

Put the cover back on.

Remove the battery maintainer or battery you used to retain the radio codes.

Start it up.

Boxterjim describes it this way (he didn't worry about maintaining the radio validation code or engine management memory):

"Porsche OEM (Moll Kamina) installed 8/29/2000 was getting weak. So, after researching things I decided to try the Autozone Duralast 48-DL. Cost is $69.99 w/trade ($10 more w/o trade) 24 month 100% warranty then pro-rated for the next 5 years.

I decided that since I had the radio code I'd skip trying to keep juice to the electronics during the swap. Figured I deal with whatever came up...(a bit risky!)

Tools:

- 13mm box/open end wrench

- 10mm box/open end wrench

- razor knife

Disconnected 10mm terminal clamps, negative first, then positive.

Stood in the front trunk to lift out the old battery. No problem.

The new battery is a perfect fit. Simply angled in the base (firewall side) to slip under the lip on the tray then scooted it snug right and bolted the hold-down bracket on the bottom left (13mm). (after cleaning out the bottom of the tray of course!)

The main difference vs. the Moll is the location of the vent. Moll is on the left end center. Duralast is in the back center. But, good news is the battery comes with a vent adapter tube and barbed connector. As you can see in the photo, there is a black right angle tube connected to the battery (right above the "t" in Duralast.) I cut this to about 1 in. (originally it was about 6 in.) I left the full length of the original clear plastic tubing and re-routed it to the back and pushed it in the barbed adapter.

Autozone gave me the felt adapters for under the terminal posts along with some silicone grease to help prevent corrosion. So, I lathered the post/terminals up and tightened the 10mm nuts. Positive first, then negative. All done with the physical stuff!

I jumped behind the wheel and turned the key...VRoOOOmMM (a great sign!)

The radio showed C O D E with the C flashing. No problem, I carefully punched in my 4 digit code and pressed the up arrow (seek) Bingo! Radio came on and had all my pre-set stations in place (some flash memory in there somewhere...)

I cycled the windows down then up. The 1/2 in. movement when a door opens/closes was working fine.

Now for the fun...time to "retrain" the computer. I hopped in the car, took down the top (which works perfectly due to last weekend's project) and took a lively drive up the Angeles Crest Highway...

Re-training complete...I headed back home.

Last step is to drop off the old Moll at Autozone and get $10."

Don't lose the Radio Validation when you change the Battery

The radio validation code is a 4-digit security feature of '97 thru '02 Boxsters which helps prevent the use of your radio in case it was stolen. It was delivered with the car on a wallet sized card and may be in your owner's manual pouch (a bad place for it as a thief might steal that too). It is also often written on the "build codes" sticker inside the front trunk or inside the service manual or warranty book.

If you don't find it there, you need to visit your dealer and, with proof of ownership and a few minutes to find your VIN and radio serial number, he can get the code for you. Now it depends on the dealer and your relationship with him if he does it for free. I've heard of $50 charges.

How you find your radio's serial number depends on the radio model.

You can read the serial number of a CDR-220 by holding the TP button down until "Becker 1" displays, then scrolling using the right hand (tuning) knob until the serial number displays.

For the CDR-210, turn the radio on and push the 8 and the last (0) preset button AT THE SAME TIME. Hold for 5 seconds. When the screen changes, hit the tuning toggle button down several times until it says serial then hit the center preset button under arrow on display and the serial number will display.

If all else fails, you can get the code from Becker for $30. Or post on renntech with serial number and sometimes a helpful soul can find the code for you.

Use the battery maintainer through the cigarette lighter to keep power to the radio while the battery is disconnected. Or use the jumper post in the fuse box and a set of jumper cables to a 12 volt battery (even a lawn mower battery would do it).

A '03 or '04 Boxster doesn't use the code system for radio theft security.

How to maintain yours during the winter

Use a "battery tender" (not a trickle charger). Trickle chargers never turn off the charging circuitry so they are fine to recharge a battery but will "cook" the battery if left on for days or weeks at a time. Tenders/Maintainers are smart and sense the level of change and only begin charging again if the voltage drops. Thus they won't "cook" the battery.

Battery maintainer’s electronics are somewhat sensitive to line voltage surges. When opting for a full featured (read more expensive) unit, a single outlet surge protector (like Radio Shack units) can prevent unnecessary problems.

Failure to maintain the battery at full charge, or under charging, can lead to “sulfation” of the positive plates. Sulfation increases the batteries internal electrical resistance, causing any type of charger to increase amperage output (and charging temperature) to bring the battery to a fully charged state, typically significantly reducing the batteries life expectancy. Many “intelligent” chargers and maintainers (but not all) include a “sulfation mode,” which tests for the presence of this condition and use short pulse charges to reduce or eliminate the build up of lead sulfate, extending the life of the battery. The “basic” Porsche model does not have this feature, while the newer “CTEK” unit does; a point worth considering when comparing units for purchase. You can also find this feature on other manufacturers as well, including the line sold by Griot’s Garage for example.

Connect it either directly to the battery or to the power socket (aka cigarette lighter). It is not necessary to get one with the Porsche name on it but, when you do, you get an adapter (picture) that makes connecting to the cigarette lighter socket trivial if your car happens to have an American socket. It can also connect without the adapter to a European socket.

The side door weather-stripping has a slot underneath the door (see picture below) in the weatherstripping that allows the cord to fit through the slot and the door to close. Better that than in through the hood directly to the battery which creates a hole to a nice nesting place for critters.

Porsche brands two battery tenders (sometimes called "maintainers"). Either is just fine for over the winter use. Don't bother using one if the expected time of non-Boxster-use is a week as the circuits that use power when the car is off are smart and check less often (and thus use less juice) the longer the car is not used.

• The cheap Porsche one is part # 980 611 981 00 and works just fine. It comes with a connector that allows you to connect it to the lighter socket plug on dash. There is also a extra-cost adapter (000 043 202 55) that contains pinch clips so you can connect to non Porsche items (lawn mower, motorcycle, etc). I use my maintainer with the pinch clips adapter on my riding lawn mower battery when I'm not using it on the Boxster. That part number is 000 043 202 55.

• The more expensive Porsche battery maintainer has a part number of 955 044 900 15 and is twice as expensive. It does charge faster if you are trying to use it as a charger. See my comments on the sulfation mode capability above; it does bring additional value in the form of life expectancy by limiting the formation of lead sulfate on the positive plates. You can also find it under it's manufacturer's name CTEK US3300 for lots less. The CTEKUS800 can be had for as low as $45 with another $10 buying the lighter socket adapter cord.

The Battery Tender Jr. at about $24 is good. If you want to connect it via the cigarette lighter call Deltran and they have been sending one for free.

A source for battery maintainers with good descriptions is here.

Plugging into the Cigarette Lighter

There have been several sizes of cigarette lighters installed on 986s depending on the model year and options ordered (smoker's package). You can retrofit the size you want with information from here.

The Optima Battery

So what is so good about an Optima? Lighter, tested to take more deep discharges, tested to take more charge/discharge cycles, totally sealed (could mount upside down, no risk of battery acid fumes causing corrosion).

What's bad? For a Porsche Boxster, the need to adapt the mounting (buy or make a plate, see below) and the need to get a special version (34R) which may take a day or two or a longer cable (see below).

Optima batteries are not gel cells as is commonly believed. They actually use “AGM” (Absorbed Glass Mat) technology that is actually a hybrid version of the traditional “wet cell” lead/acid design everyone is familiar with. The AGM design uses a fiberglass “sponge” like material to keep the electrolyte (acid) in contact with the plates. When combined with their “spiral cell” mechanical design, it produces a lightweight sealed package with excellent power output (particularly at low temperatures); as well as their famous “six-pack” look. In addition, the Optima’s can be charged with conventional chargers or maintainers. True “gel cell” batteries use a thyrotrophic agent to create a gel-like mass from the electrolyte. While otherwise similar in design to wet cells, true gel cells have many limitations; including very weak cold weather performance, very slow charging characteristics, and the requirement for very specific chargers to prevent cooking the battery. This is why they have never been broadly used in automotive applications.

Optima Battery link

I recently received the following note from "Gary in NE" in response to a query about Optima batteries and their mounting.

"Mike: I recently put the Adapter in my car with adapter kit. I did the change in 20-25 minutes. I have a full set of tools and a heated shop to work so was no problem.

The plate comes in brushed aluminum or texture surface black plastic. All fittings are Stainless Steel and the new cable has EOM cap for coverage of the "power distributor" attachment. I was not able to locate or order a 34R battery so had to use the 34 model necessitating the longer cable.

I purchased the kit with aluminum plate and the longer cable. It is too pretty to hide under the battery!

Prices are: Aluminum Plate Kit $49.95 + $6.00 for S/H.

Plastic Plate Kit $29.95 + $6.00 for S/H

Long Battery Cable $17.95 + $6.00 for S/H

* If kit and cable is purchased at same time, S/H $7.00

I also bought the "thumb screws" for $24.95 + $3.00 S/H

Battery Maintainer $39.95 + $6.00 S/H

I had gone through several batteries in my car and, with the very limited warranty on the replacement battery for Porsche, I decided to make the change. I have had Optima in all my other cars and pick-up and as a matter of fact I have one of the 34 model that is going on 9 years and another on 7. So, much longer life that the OEM battery.

I switched many years ago before the Optima became well know. I had a battery crack in my wife's new car and, with the damage the acid did, that was it for lead acid liquid batteries. Two years ago I saw a friend in Phoenix's battery in a car explode. Fortunately he was away from the car after parking it. What a mess that was.

I have found that the Optima lasts longer and takes longer to loose a charge. Longer cranking time in cold weather. It weighs slightly less than the Porsche OEM too. Sounds like a commercial for them, but I am not in any way associated. Wish I was the way they are selling.

If you can obtain the 34R model you will not need the new longer + cable. (False)

I understand that Yellow Dog is in the process of getting their web site up but until then you can reach them at (563) 386-0675. Ask for Jan. (The web site is now up here.)

Yellow Dog Motorsports

801 E. 59^th Street

Davenport, IA 52807

(563) 386-0675

Here are the written portion of the instructions:

Because of the high incidence of battery tray corrosion on Porsche models 986, 987 and 996’s we have tried to find a simple way to keep this from happening. We, like others, have been unable to determine the exact cause, except in the case of battery case cracking or battery explosion.

The best way to avoid these problems is to replace the standard lead-acid battery with a completely sealed gel or solid battery. Optima batteries fit this specification. They have no lead-acid by-products and are lighter in weight. The disadvantage is that they do not easily drop into the Porsche battery spaces in the 986, 987 and 996 models.

Installation into one of these cars is not too difficult and can be accomplished with the use of an adapter for mounting and in some cases a longer battery positive cable.

Yellow Dog Motorsports has produced a simple mounting adapter kit which comes complete with all mounting hardware and complete easy to read instructions for the change. The adapter is available in brushed aluminum or black high strength textured surface plastic. All hardware is stainless steel. All parts are machined to exacting specifications.

The Optima battery to be used is either the 34 Red Top or the 334R Red Top. On the 34R the positive and negative posts are set on the back of the topside of the battery rather than on the front.

*If you can purchase a 34R battery, the longer Positive Battery Cable will not be necessary and the original one can be retained. (False) However, we have found that it has been difficult to locate the 34R model and so most must use the standard 34 Red Top, necessitating a longer Positive Battery Cable. Yellow Dog Motorsports has a longer cable available for those situations. *Part #LPC9867966 (Mike adds here I ordered my 34R online with free shipping and it was cheaper by $30 than any local auto parts store was. I had my UPS tracking number 6 hours after order. The part came from NE so the free shipping by surface took some time to get to NC. You can pay for faster delivery including next day.)

Tools you will need for a quick and efficient installation

Torx

#20 Torx screwdriver or bit

10 mm open end or boxed end ratchet wrench for loosening the OEM battery cable nuts

3” extension and ratchet socket handle

13 mm socket for removing and installing the hold-down bolt on the battery, battery tray

bolts, and the retaining nut for the positive (+) battery cable where it attaches to the

power plug on the firewall.

Phillips screwdriver for installing the screws into the adapter.

10 mm socket with 6” extension and ratchet for tightening the nuts on the screws that hold the battery to the adapter.

The procedure for replacing the stock battery with the Yellow Dog adapter is as follows:Please be sure that you have your radio code for early model year Boxsters ('97-'02) as you will most likely need to use the code to re-program the radio after replacement of the battery.

1. Remove the battery cover.

2. Disconnect the negative (-) battery cable and cover the cable end with a plastic bag or rag to prevent any accidental contact with the battery or surrounding metal of the car. *original battery nuts use 10mm wrench

3. Remove the battery positive (+) from the battery post.

4. Remove the # 20Torx screw from the left cowl cover and lift the cover off if you are going to replace the (+) cable. It is not necessary to remove the cover if you have a 34R battery and will be using the original (+) cable

*Note: Yellow Dog has a black anodized knurled aluminum knob kit for anyone who wants to replace the right and left cowl retaining screws with something simpler to use and better looking. Part # GMP20.

5. Unbolt the battery mounting hold-down bracket on the passenger side of the battery. *uses 13mm socket.

a. Remove the clear plastic vent tube from the battery and place out of the way.

b. Move the battery to the passenger side and forward & then lift the battery out.

6. If there is any corrosion or rust or the battery tray is damaged, remove the

Four 13 mm nuts securing the tray and remove the tray from the car.

7. Clean the tray with baking soda/water mixture, remove all old or loose paint

and thoroughly dry the tray in preparation for painting, if needed. The tray

must be completely trace free of any acid or rust or the corrosion will return.

Paint and reinstall the tray.

8. If you have an Optima 34 model battery, the Original Porsche positive (+)

cable will not be long enough to attach to the Optima. Therefore it needs

to be re placed with a longer one or the cable available from Yellow Dog.

*Part #LPC9867966

If you will need to replace the (+) cable with a longer one, it is easier to do this if the plastic “cowl cover” is removed to gain access to the area. The cable is attached to the “power distributor” on the firewall of the car body via an 8mm nut that uses a 13mm socket with short extension & ratchet wrench.

Simply pull the protective black cover cap off the nut and remove with the socket.

Attach the new (+) cable to the power plug and don’t forget to snap the black protective cover cap in place.

Mounting the battery to the adapter plate:

Insert each of the flat head 6 x 30mm screws into a countersunk opening in the bottom of the adapter and screw each in until each is firmly tightened. Place the adapter on a flat surface with the screws pointing up.

Place the battery down over the screws with the screws coming through the four mounting holes in the lower part of the battery case.

The adapter will be placed with the three larger holes on the passenger side of the car and the holes will be directly over the threaded openings in the battery tray.

Be sure that you have the positive post of the battery on the passenger side of the adapter.

Place the washers over the screws followed by the four 10 mm nuts and tighten firmly.

If the battery tray was removed for repair or repainting it should be replaced and then the battery is ready to insert in the car.

Installation of the battery into the car:

Lower the battery and the attached adapter into the battery compartment and set it on the battery tray. You will need to “tilt” the unit slightly to the rear of the car as you set it onto the battery tray. This will allow the adapter plate to go beneath the retaining ridge on the back of the tray. The battery will now set flat on the tray. Push the adapter as far to the driver’s side as it will go and it will engage the retaining ridge on that end of the tray.

Use the original hold down bolt or the new 8 mm bolt and washer to bolt the adapter to the original battery tray through the hole closest to the battery.

Remove the plastic handle from the battery.

Attach the positive (+) cable to the (+) battery post and tighten. Attach the (-) cable to the (-) battery post, replace the left cowl cover and the battery cover.

Re-program radio with proper code.

Don’t forget to save all unused parts for possible use in the future.

Happy driving."

Mike's experience was:

Had some erratic starting. Some odd won't seem to charge issues. While I was sorting those out, ordered the yellow dog mounting plate in plastic. Came nicely wrapped USPS with a set of nuts and bolts and about 8 pages or instructions which you could pick up off the net from Yellow Dog's web page. Just in case I needed a new battery.

Then finally determined it was in fact the battery and ordered the Optima. Went the 34R route as the cheapest price I found was web-order and included shipping. I didn't have to be in a hurry as the P-car isn't my only driver. So I could wait for the right one...or was it the left one since the positive terminal is on the left....I kept repeating "left" as I read of another battery swap where the guy got it in backward and fried all sorts of expensive parts. Got tracking number email.

Battery arrived well packed, shipped from NE so it took 4-5 days to get to NC including a weekend. UPS and dropped at my door. Came fully charged to 12.2v with plastic coverings over the positive and negative terminals so you don't short yourself while you are fooling around with it. Also a nice removable handle to help you load the battery and mounting plate into place and then remove the handles so they don't interfere with the cover that goes over the battery compartment.

Brought it into the house, got out the mounting plate and started in. The instructions are wrong for the 34R and the battery needs to be shifted over to the left-most 4 mounting holes to get the positive terminal cable close enough to connect. And it does that just barely. Had to really struggle when I got to that point.

Everything went fine till I had the old battery out, new battery in and tried to get the negative cable from the ground point to the battery to connect. It was about 2 inches short (and I thought the 34R was the antidote to that and you wouldn't have to change the negative cable length if you ordered the 34R. WRONG.)

But the good news was Autozone had a 2 gauge (really thick to carry that starting current, don't use their 4 gauge ones, OEM looked 2 gauge) 15 inch cable part # GT215B $6.99. Only issue is it uses a 1/2 inch wrench to tighten the bolt so the positive cable post bolt and the negative are now a mix of metric and not. I suppose I could have used the bolt out of the old cable and kept them both metric but I had a full set of tools handy and wanted to see if things worked NOW. The cable also came with colored plastic covers for the terminal posts. No need to add any anti-corrosion stuff to the posts as the battery is sealed.

Had I known all this, I could have done it in 15 minutes. As it was, an hour and a half later and a trip to Autozone and the key turned and the car fired up. And no odd lights came on. I'm sure I'll need to reset the clock and re-enter the radio code..recorded somewhere...maintenance manual or hood??? (File on my web site..who steals CDR-220s anyway)

Does the Optima make sense? Probably not from a financial standpoint. I could go to Autozone and get them to install one of their medium grade batteries every three years for the price of what I paid for all the Optima related parts. But it sure looks pretty in there. And starts up with eagerness I had forgotten it had.

The old battery I had in the car, an Interstate, had the vent tube installed, its terminal pristine, and the battery tray was perfect and shiny. I did find some stray leaves and pine needles down near the drain holes to the sides of the battery and so took the time to remove them.

My impression was that there wasn't a great deal of weight difference between the two batteries just judging from the effort to get them in and out. Though I'm sure there was.

I did use the climb into the trunk trick and had all my tools at the ready on the plastic to the left and right of the center battery compartment.

There are even lighter batteries used in racing to save weight. But you have to be careful as they have little reserve and cold weather or heavy use of accessories (night driving, A/C or audio amps) can quickly drain them.

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