Reluctant to go into gear the first time each morning

2010 Prius with nav package. Always kept in garage. Usually driven 4 or 5 times a week, but recently the car sat for roughly 3 weeks unused. That's when the problem started.

I'm accustomed to the typical 2 or 3 second wait before the gear shift lever sends a signal to the dashboard. What's different now is the car won't shift out of "P". Well, it finally does, but not like before.

After pushing the "Start" button I can hear the nav system starting up (a soft skritchy sound that reminds me of a hard drive seeking data), the typical advisory notice appears on the nav screen, everything acts like normal. But the dashboard gear indicator remains in "P" when I nudge the lever to "R". What seems to be happening is if I press the Start button a second time the dashboard will give me an "R" when I ask for it.

If we go into town to run errands the car will act like normal. Starts up, goes into gear just like it always has. AFAICT the reluctance to shift into "R" only exhibits with the first startup of the day.

Yesterday the windshield wipers were still on when I pushed the "Start" button. The arms dragged across the windshield very very slowly before the ICE motor started . The weather has been cold, the car sat for a few weeks - could this problem be the 12V battery?

 

Original battery, so about 10 years old. Unfortunately, I've run the battery down hard about 4 times by leaving a dome light on overnite. That probably hasn't helped any...

IIRC the 12V battery doesn't have fill caps so I can't check for electrolyte levels.

 

OK thanks guys for the quick responses.

Thanks for the Christmas wish! I don't want to sound all politically correct, but I don't want to be non-inclusive either. However you celebrate this time of year, I hope everyone has a happy and fulfilling holiday season!

Ouch I didn't know the 12V battery for the Prius is AGM and expensive. Should I just go to the dealer?

 

OK, thanks, I googled a bit and came across several PriusChat threads discussing the issue of battery replacement. Right now I'm leaning towards taking it to the dealer and paying the price.

 

I'm gonna contact our dealer this morning. Got a question for the group - will the car dump any settings or tweaks if it takes me a half hour or so to swap batteries?

For instance - years ago someone at the dealership hooked up a laptop and changed the reverse beep setting from that annoying continuous beeping to just one beep when you first put the car into reverse. Will the car go back to default?

I'm debating between replacing it myself vs. just letting them do it, but just for my own peace of mind I'd like to know the answer to this. The car didn't go back to default after the times I'd run the battery down by mistake, but that's not really the same thing as no battery at all.

I imagine that a person could just clip a 12V motorcycle battery to the loose terminals to keep a charge on the car. I don't have one. I do have a little 12V solar panel that plugs into the cigarette lighter. Would that work? I don't know if the lighter is disconnected from the rest of the car when the car isn't "on". It would be easy to test for that. I've got a few cigarette lighter to USB adapters. Plug one in to the cigarette lighter receptacle, plug my phone into the adapter, see if the phone starts charging.

EDIT: I guess I should look before asking. Found at least one PriusChat thread that claims the 12V outlets are not live when the car is off. One forum member suggested connecting a charger to the jump points under the hood. I know where the positive tab is inside that box, but never been sure about where to put the negative lead.

 

Hey, thanks for the pictures.
Just remembered I've got a little motorcycle battery charger. It's hardly bigger than your typical wall wart. That would probably be better than using the full sized car charger on its "trickle" setting.

 

OK, that's interesting you didn't lose the single reverse beep.

I peeled back the layers over the battery. Put a digital multimeter across it. 9.9V

Called the dealer. $330 to have them do it. $210 for just the battery.

The service guy said it might not be the battery. If I pay them to do the whole thing they'll do their diagnostics. I think I'll take my chances that it's the battery. I've found the hard way that the simplest solution is often the right one.

BTW, I followed some PriusChat directions to get to the Diagnostic screen. Didn't work. Our car has NAV. Directions said set the park brake. Two pushes on the Start button with foot off the brake. Hold down the "INFO" button (ours says INFO/PHONE) while flicking the headlights on/off 4X. Didn't work.