Confusion over acc, ig-on, and ready...which is best?

Nos402 · 05-22-2006, 09:48 AM

So I think I understand what each of the ACC, IG-ON, and Ready does, but here's a few things I'm not sure about:

If I'm just sitting in a parking lot, waiting for someone, and I want my A/C and radio going, which mode is best? Don't I want it in full "Ready" mode so that the gas engine can kick on if the battery starts getting low? I just don't really get when or why I would use ACC of IG-ON modes.

Also, when going through a car wash, which mode do I want to be able to keep it in neutral? Again, wouldn't I want full on "ready" to avoid draining the battery? Is there any way to put the car in Neutral without it being on at all?

Thanks so much. I've been searching the forums for these answers, but haven't found them yet (I'm sure I must have just missed them, and will probably find them as soon as I hit "post")

richard schumacher · 05-22-2006, 09:55 AM

Sitting with A/C and radio on: use READY. A/C drains the traction battery in a hurry, which can harm the battery. Why take a chance? (Oh, and it must also be in Park, because in Neutral the engine will not charge the battery.)

I never use automatic car washes and so have not worked out the right mode.

eagle33199 · 05-22-2006, 10:15 AM

Personally, i would say it's the same as a normal car (except you have to remember that the 12V battery in the prius is fairly weak). the only real difference is that, instead of turning a key to different positions, you have to hit the power button

**efusco** · 05-22-2006, 10:45 AM

1)ACC won't run the A/C
2)If your wait will be short (less than 5 minutes) it probably doesn't matter if you're in IG-On or Ready...it's unlikely the ICE will come on unless your initial SOC was quite low.
3)It probably makes most sense to leave the car in READY. You don't get your start-up penalty for the emissions process, you don't risk draining the accessory battery.
4)When you become a fuel economy geek like me you'll just roll down the windows, put the car in ACC mode and just listen to the radio, sweating, while you wait!

seasalsa · 05-22-2006, 10:53 AM

<div class='quotetop'>QUOTE(Nos402 @ May 22 2006, 06:48 AM) [snapback]259178[/snapback]</div>

Quote:

So I think I understand what each of the ACC, IG-ON, and Ready does, but here's a few things I'm not sure about:

If I'm just sitting in a parking lot, waiting for someone, and I want my A/C and radio going, which mode is best? Don't I want it in full "Ready" mode so that the gas engine can kick on if the battery starts getting low? I just don't really get when or why I would use ACC of IG-ON modes.

Also, when going through a car wash, which mode do I want to be able to keep it in neutral? Again, wouldn't I want full on "ready" to avoid draining the battery? Is there any way to put the car in Neutral without it being on at all?

Thanks so much. I've been searching the forums for these answers, but haven't found them yet (I'm sure I must have just missed them, and will probably find them as soon as I hit "post")
[/b]

If I'm just sitting in a parking lot, waiting for someone, and I want my A/C and radio going, which mode is best? Don't I want it in full "Ready" mode so that the gas engine can kick on if the battery starts getting low? I just don't really get when or why I would use ACC of IG-ON modes.

Just push the PARK button This will allow the ICE to keep the battery charged.

Also, when going through a car wash, which mode do I want to be able to keep it in neutral? Again, wouldn't I want full on "ready" to avoid draining the battery? Is there any way to put the car in Neutral without it being on at all?

Just put it in Neutral When you leave the car wash put it back to DRIVE.

These answers assume that you have just driven up to the car wash or the parking lot.

Betelgeuse · 05-22-2006, 10:56 AM

<div class='quotetop'>QUOTE(Nos402 @ May 22 2006, 09:48 AM) [snapback]259178[/snapback]</div>

Quote:

Also, when going through a car wash, which mode do I want to be able to keep it in neutral? Again, wouldn't I want full on "ready" to avoid draining the battery? Is there any way to put the car in Neutral without it being on at all?
[/b]

Just to address this: the battery will not charge when the transaxle is in neutral (or, so the MFD tells me when the door is open and I'm in "Drive"). So, having the car in "Ready" will not charge the battery if you're in neutral. That said, I think that "Ready" is the best state to be in when going throught the car wash; there's no penalty to being in "Ready" and it just means that you're prepared to drive off when the car wash finishes.

auricchio · 05-22-2006, 11:25 AM

Actually, Betelgeuse and seasalsa are in agreement about the car wash mode. If you drive into the car wash and choose Neutral, the car will still be in Ready mode. It won't charge, but the car wash shouldn't last long enough to make a big difference in SOC.

The real question is: What would the guys at an attended car wash do! If they press Power to turn off the car, it'll revert to Park. I don't even want to think about that.

eanda9000 · 06-01-2006, 12:22 PM

yeah, last time i took my car to an auto car wash, mine was the only one going through with someone sitting in it. i dont even what to think about what transpired. next time i will sit in the passinger seat just to make sure the drivers know what to do.

05-22-2006, 10:45 AM	#4
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 14,050 My Car: 2004 Prius Package: #9 Nominated 1 Time in 1 Post TOTM Awards: 0 Friends: 23	1)ACC won't run the A/C 2)If your wait will be short (less than 5 minutes) it probably doesn't matter if you're in IG-On or Ready...it's unlikely the ICE will come on unless your initial SOC was quite low. 3)It probably makes most sense to leave the car in READY. You don't get your start-up penalty for the emissions process, you don't risk draining the accessory battery. 4)When you become a fuel economy geek like me you'll just roll down the windows, put the car in ACC mode and just listen to the radio, sweating, while you wait! __________________ Evan E. Fusco, MD Seaside 04BC9/OEM EVb/NAV & auto-BT/XM Radio, CAN-View, Shark Fin, BT Stiff. Plate, Skid Plate & Strut Support

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05-22-2006, 09:48 AM	#1
Nos402 Join Date: Jun 2005 Location: Austin, TX Posts: 16 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	So I think I understand what each of the ACC, IG-ON, and Ready does, but here's a few things I'm not sure about: If I'm just sitting in a parking lot, waiting for someone, and I want my A/C and radio going, which mode is best? Don't I want it in full "Ready" mode so that the gas engine can kick on if the battery starts getting low? I just don't really get when or why I would use ACC of IG-ON modes. Also, when going through a car wash, which mode do I want to be able to keep it in neutral? Again, wouldn't I want full on "ready" to avoid draining the battery? Is there any way to put the car in Neutral without it being on at all? Thanks so much. I've been searching the forums for these answers, but haven't found them yet (I'm sure I must have just missed them, and will probably find them as soon as I hit "post")

05-22-2006, 09:55 AM	#2
richard schumacher nacreous lacquer Join Date: Mar 2004 Location: United States Posts: 4,096 My Car: 2004 Prius Package: #6 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Sitting with A/C and radio on: use READY. A/C drains the traction battery in a hurry, which can harm the battery. Why take a chance? (Oh, and it must also be in Park, because in Neutral the engine will not charge the battery.) I never use automatic car washes and so have not worked out the right mode.

05-22-2006, 10:15 AM	#3
eagle33199 Platinum Member Join Date: Mar 2006 Location: Minnesota Posts: 3,600 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Personally, i would say it's the same as a normal car (except you have to remember that the 12V battery in the prius is fairly weak). the only real difference is that, instead of turning a key to different positions, you have to hit the power button

05-22-2006, 11:25 AM	#7
auricchio Senior Member Join Date: Mar 2006 Location: Cambria, CA, USA Posts: 853 My Car: 2006 Prius Package: #8 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Actually, Betelgeuse and seasalsa are in agreement about the car wash mode. If you drive into the car wash and choose Neutral, the car will still be in Ready mode. It won't charge, but the car wash shouldn't last long enough to make a big difference in SOC. The real question is: What would the guys at an attended car wash do! If they press Power to turn off the car, it'll revert to Park. I don't even want to think about that.

06-01-2006, 12:22 PM	#8
eanda9000 Join Date: Apr 2006 Posts: 36 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	yeah, last time i took my car to an auto car wash, mine was the only one going through with someone sitting in it. i dont even what to think about what transpired. next time i will sit in the passinger seat just to make sure the drivers know what to do.