Auto wipers and battery drain

[Woody14619]

As Mark noted, this happened in the '08 in some cases (with the full package, alarm etc), but was much more noticeable in the '09 due to a component change. There was a "fix" for the '09 units that replaced a part with the same system as the '08 units. This is also part of the reason the battery was updated in '08 units with the alarm and rain sensor packages.

To the original question, I don't think it would be that simple. The reading of the stalk is done via a resistive value. While one could rig a relay to switch off the line to a fixed relay value, it would be quite a pain. If you're having this issue, take your car in for service and tell them what's going on. They will probably fix the issue as recall/warranty for free.

[SmartDigger]

It only started happening after they flashed the system for the fuel gage 7/8 issue. It also only happens when the two are on. I leave the auto lights on all the time. It could be total coincidence also. battery went too low to start the car twice. both time the wipers were left on and car set for over 24hr ( rarely does It sit that long) I checked with the dealer after it first happened ( 2 days after the flash) and he said there is no possible way anything he changed could have made this happen. The other variable is the battery is starting to go south.

[Woody14619]

Originally Posted by SmartDigger

I checked with the dealer after it first happened ( 2 days after the flash) and he said there is no possible way anything he changed could have made this happen.

Since 90% of the car's functions are controlled by the computer (including auto-features), a software change can always have an odd side effect. I'd still lookup the thread that was about this on the 09. I seem to recall there was a part number (or at least a good description) listed for what changed in their "fix" for the 09s.

I know that in my 08 with the full package I had a similar issue, and had my battery drain to a no-start state a couple times a well. Since I live in a state where you legally must have your lights on if you are using your wipers, whenever I turn on auto-wipers I also turn the lights to manual-on. The binging noise when I go to get out of the car reminds me that the lights are on, and when I set them to auto, I disable the wipers. So... Now that I've been properly "trained" I don't have this problem any more.

[SmartDigger]

I am more worried about the wife forgetting than me. I know what to do if I have a dead battery.

[jwight]

I know of at least one 09 that lost the DRL function after the ECU was flashed to correct the 7/8 fuel gauge problem, so yes, a reflash can affect other things on the car.

[SuperGeek]

Check the size of your battery. If you have the old 42AH battery, that's the same battery that for me started to show low voltage after a year and 6000 miles. Short trips, auto settings everywhere just ran the battery down little by little and it never charged up enough to counteract it unless I went on an hour-long highway trip. Seriously, the OEM 42AH battery had problems of its own, so if you've got that one, your easiest and cheapest fix is to get a new battery - either through dealer/warranty or out of pocket. A better battery can handle the slow drain of the feature; all cars nowadays have electronics that run at a few milliamps 24/7. I can leave my car for a week and it still shows 11.9V before starting again.

* The Scangauge is a great tool to show your voltage trending down over time, and if you see the voltage under 11.5V before you crank up (lights off), your battery's slowly losing the battle.

[SmartDigger]

I have the bigger battery. It could be the battery going south. Time will tell.