The 4 year-old Porsche factory battery died today in the Home Depot parking lot, so I hitched a ride across the street to Autozone. They sold me a battery for $89, and I hitched another ride back to my car. We jumped my car with jumper cables, and then I drove home and installed the new battery.

The car quickly fired with the new battery, but it gave me a ! PSM Failure warning after it started. The cruise control did not engage on the way home after the jump, but it is working fine now.

Thoughts?
Nick

 

normal after a battery disconnect. it will clear after driving for a while.

 

Thanks!

 

I had a battery brown out on my first 997, the low battery caused the computers in the car to brown out, all the electronics except for Wipers and Windows failed (including turn signals).

Dealer had to disconect all the computers esentially restarting them. They also charged the battery and I was good to go. I know use the OEM trickle charger when my car is resting for long periods it stays in, or every week I charge it up one night.

 

My battery died. Porsche roadside failed to jump it, so was flatbedded to dealer.

They tested it and notified me it needed replacement for $350.

Since there was a psm failure code they said that if I replaced the battery myself they would need to clear codes and charge me.

Reluctantly, I told them to do it.

Did they lie to me? Would the error codes have cleared themselves as a prior poster stated?

I hate getting ripped off!!

 

I've disconnected my battery several times to effect the DME reboot procedure and not had any issues save for the PSM fault code which goes away after a minute or two of driving. However, I recently read an article about dead batteries and the 99X Porsche models that indicated the car needs to be energized while the battery is being replaced or the loss of computer data would occur which required a trip to the dealer and a hookup to the PIWIS. Can anyone on this forum shed some light on the issue ?

 

The PSM failure on battery disconnect is documented in the owner's manual (page 261??) and is cleared just by driving.

 

I didn't even think to look in the manual! Will check. I feel foolish for accepting their claim.

I should call them on it. But what to do. I need them to diagnose an unusual squeal I hear that I think I is from the clutch.

 

I had my battery connected all winter long once....NO issues,but maybe I got lucky!

Stacy

 

Yes, they lied to you. PSM code clears itself after driving about a mile. Other codes will not clear themselves (like check engine) and require the PIWIS to clear.

$350 for a new battery? Yikes.

 

Just came back from the dealer. They replace the battery with an Interstate MTP-91. I was surprised that it wasn't a Porsche branded battery. They billed me about $145.34 for the battery and $154.61 to test and replace the battery + tax. This was not covered by the CPO warranty, even though I drive the car more than the threshold 600miles per month. (They won't warrant the battery, even the original warranty, apparently, if the car is infrequently driven) I'm in the process of asking for some concession from the dealer.

I read the article in this month's "Excellence" magazine on battery issues like some other folks seem to. It made me wary of replacing the battery myself, but many others on this forum seem to have had no problems replacing the battery.

Some lessons learned:

1) If you get a jump starter box with a cigarette lighter adapter and a male-to-male cigarette lighter cable, you can maintain power to the car while changing the battery.

2) A really dead battery may not be successfully jumped with jumper cables from a car or even truck. I watched the Porsche roadside guy try with a plug in charger, then with jumper cables from his C Class Mercedes. He failed. The flatbed operator said many methods fail to start a really dead battery.

3) One of the few jump starter boxes that will jump a Porsche with a totally dead battery is the Snap-On red colored box. I watched the flatbed operator do it. The flatbed guy said he bought it a few years back for $300. The only model on Snap-on's website is blue in color and $200. I don't know if it is a different spec.

4) This was a huge PITA!

5) I'm buying a trickle charger. Don't know which one yet. My cousin in Canada who is doing research on battery longevity for a car mfgr is sending me one that they like. Will report back. Porsche charger is $$

 

If your car met the minimum mileage standard of 6K miles per year (I think that is the number), how can the dealer not cover it? Sounds fishy to me.

 

Let me correct what I wrote......
I had my battery ****dis-connected **** all winter long once....NO issues,but maybe I got lucky!

I also have disconnected the battery numerous times with some of the mods I have done and like mentioned above IT did clear itself!

Stacy

 

Great to know. Next time, I'll be prepared

 

Do those <$10 battery memory maintainers that use a 9V battery plugged into the cigarette lights actually work on a Porsche? Would they eliminate the temporary failure code?