replacing battery

Chicobiker wrote:

Tricky? Sometimes it's tricky getting the terminals off - easier with a box end wrench. Sometimes requires twisting and GENTLE prying. Write down your radio station presets. Car off, lights off, doors closed etc. Put on safety glasses. Remove battery hold down clamp. Usually, loosening and unhooking from the bottom is enough. Disconnect neg. (black) terminal first (there could be some small sparks - don't worry) and secure outta the way. Disconnect pos (red terminal, secure, remove plastic shield if equipped, and carefully remove battery being careful not squeeze the sides in much or spill fluid. Set aside. If you have a small wire brush or a special batt. term. cleaner, brush the inside of each terminal till mostly bright metal shows.Also, use a flashlight if necessary and inspect the batt. tray for excessive corrosion, clogged drain if equipped and familaiarize your self with the batt. hold down clamp hook locations. Carefully place new battery in car in correct position. Put plastic shield on battery, if equipped, do not leave out as it may be desiged to direct cooling air/shield hot air, etc. Put pos (red) cable on new batt. and secure. Place neg. (black) cable, watching for small sparks, and secure. Smear dielectric grease over each connection. Install hold down. Inspect battery for proper fluid level - only top-up with demineralized/distilled water. Carefully inspect under hood area for rags and tools. Clse hood, start car, program radio!

Carl

Carl gave you an excellent procedure. The only thing I'd add is that when working on the first and last terminal (i.e. the negative terminal, work with one hand behind your back.

And don't use a wrench long enough that you might touch it to the positive terminal while working on the negative. That'd be bad.

Finally, I recently replaced a top terminal battery on someone's car with one of those side terminal + top terminal batteries. The top terminals were setbac from teh edge of the battery further than the battery we were replacing, so we had to do some creative bending of the factory terminals to flatten them to get them to fit.

And no, it's not that hard.

Oh, and if there's corrosion on the terminals, baking soda is nice to throw on it. It's a base and will neutralize the acid that might be around make it a little easier to clean.

In a pinch, if you don't have dielectric grease or electrical contact grease, vaseline seems to work just fine.

-- Todd H.

All good. I'd only only add - if you're wearing any rings, *please* take them off before you statr working - just in case! Cheers

Yes!! I learned that lesson when I stuck my hand behind a car dashboard while wearing a metal-banded watch. Result ... sparks and a burned wrist, not to mention blown fuses.

Incidentally, there is a way to preserve the car radio memory using a nine volt battery and a cigarette lighter plug, but probably not worth the effort unless the radio has power off security protection. Cheers

That one made me laugh! Thanks.

And thanks for the tip on taking off the rings too.

Programming the radio is annoying, but no big deal.

Chicobiker

Some radios may use flash memory or otherwise retain the settings. Also, some security systems will freak out and beging flashing lights, etc. Just hit the unlock on the remote several times, or maybe cycle the ignition key on-off 3 times/whatever and it should be back to normal. It seems complex all written out but should be a 45 minute job or so for a first timer - probably under 30 miniutes you secong time. Don't rush - do it right and you won't need to pay someone to re-do it.

Carl

Actually, it's far more effective to slowly trickle a full jug of boiling water over the terminals. Just loosen the top vents first, as the heat causes slight venting and some batteries do that too slowly - you could crack the casing.

Excellent post Carl.

I have seen TSBs from some manufacturers that require technicians to use a booster battery connected to the car, while replacing a vehicle's battery.

The reason given, is that in newer vehicles there are so many settings that would get lost (radio, seat, steering wheel, pedal, mirror, climate control, navigation, etc) that is not worth the aggravation. Not that this is this the case with the 03 Sport, but...

I wash the battery, tray, frame, retention brackets, etc with a solution of baking soda and water, until i see no further gassing of the solution. This neutralizes the battery acid. I add baking soda to the water until the water gets a lil "merky" with the soda. I use an old tootbrush to clean the terminals and alike.

I have been using vaseline in battery terminals forever, with excellent results. After all the post and terminals are clean and dry, I put the vaseline on them before putting them together.

Besides, I try to set the terminals as high as possible on the posts, as to keep battery acid away from them as much as possible. Some use the felt disks covered with vaseline (grease) for the same purpose.

Good luck

Chicobiker wrote:

In addition to what others have said, I'll add some more info. When the battery is disconnected, in addition to the radio presets being lost the ECU loses its "learned" values for timing and idle. So, when you next start and drive the car you may notice that the idle is a bit erratic initially and performance and fuel mileage may be different. These things will eventually return to normal as the car is driven over a few days. To prevent this, as well as retain the radio settings, you can use a "memory saver" which can either be purchased commercially or made yourself. This consists of just a 9V battery and a diode in series (to prevent the car battery from backfeeding into the 9V battery which would make it explode). These devices are usually sold with a lighter plug but unfortunately that won't work with Subarus (and most other foreign vehicles) because the socket is switched with the key. So, what I do is use clipleads to connect the backup directly into the fuse box to a constant 12V point (on my WRX there is a convenient stud that is one of the terminals for a main fuse) and that works well. The 9V battery is sufficient to retain the memory in the radio and ECU, as long as you use a fresh 9V and make sure NOT to drain any current while the car battery is disconnected. This means the key must be out of the ignition, and the doors and trunk must remain closed.

You can avoid these no battery situations if you have an extra 12 battery you can connect via jumper cables to the cars battery cables. Doesn't have to be a large battery, just enough power to hold systems up during the couple mins the car battery is disconnected.

Mickey

I've got an emergency jump starter. The only problem would be where to rest it without risk that it falls over and takes out some critical part.

Can't be too complicated. I did one in my driveway at night in -20C weather.

Yep, an older vehicle could drive oddly for a few drive cyclse as the ECU adjusts for worn/lazy sensors.

good point

It seems it IS tricky changing a battery! look at the posts?

hah!

Carl

Hi,

Just be sure you know if there's a security code that needs to be input to keep the radio working after the new battery goes in. Some of 'em die when power's disconnected to discourage theft...

Rick