How long can I idle in maintenance mode?

you can idle until you run out of gas in 'park', not sure about maintenance mode.

 

I don't think there's any harm in just sitting in the car with the AC, without being in Maintenance Mode. The engine will cycle on/off as needed, whenever the state of charge runs down I think?

I would never do this, would ruin my (mediocre) Fuelly score for starters. Car's not going anywhere, I turned it off. Roll down the windows, as needed. Get out and sit in some shade, as needed. Course I'm a little further north, lol.

 

^ this. Is there more to the story of why you want maintenance mode for this, when the car makes an extremely efficient air-conditioned hotel room in ordinary READY mode, as oodles of Prius-campers will confirm?

 

There are two different maintenance modes: one for exhaust gas testing (just makes sure the engine doesn't cycle off) and one for dyno testing (disables the skid control).

I had not read that either one would destroy your inverter. Driving in the dyno mode can overrev MG1 if the wheels slip, doing mechanical damage, or perhaps (I suppose) overvolting the MG1 section of the inverter.

I'm not aware of any adverse consequence of the exhaust gas maintenance mode, other than the obvious, fuel consumption and CO and CO2 output.

Prius-campers are generally very relaxed about CO-related risks, but that's because they are running in normal READY mode, not with the car rigged to run the engine continuously. CO doesn't pose any risk to the car, and you didn't ask about risks to you.

I think my preference would be to learn to sleep through the starts and stops. I think it took me most of one night. (For years I slept in my bedroom through the noise of a 1980s gas furnace that sounded like somebody banging a pot and lighting a flamethrower every time it kicked on.)

 

The gas-powered air freshener, ugh...

 

Davey Crockett would roll over in his grave, lol.

 

Maintainence mode does not charge the HV battery, I thought.

The AC runs off of the 12v and not the traction battery ( I think). The 12v is continuously replenished from the HV battery when the car is READY. IG-ON is powered from the 12v only.

Posted via the PriusChat mobile app.

 

Prius-camping threads often discuss whether to keep a CO alarm in the car. It's generally regarded as more of a peace-of-mind option for people using the Prius as a Prius, where the engine is only running several minutes every hour.

For your usage, I would more strongly suggest one. The emissions of a Prius continuously idling all night are very little different from those of any gasser being used the same way, and the risks should be taken equally seriously.

 

Whatever you decide to do, I promise not to take it personally.

In case anybody else reading has never heard of such a thing, here are a few links from a moment of googling:

https://www.cbc.ca/news/canada/edmonton/carbon-monoxide-poison-drayton-valley-conklin-exhaust-1.4484037

ScienceDirect

CDC - Carbon Monoxide Poisoning - Prevent Carbon Monoxide Poisoning on Your Boat (happens to be about boats, which also sometimes idle in open air)

 

PLEASE, PLEASE get a Carbon Monoxide alarm!

The risk is, that if you are parked, the exhaust gases are blown by the wind. If your car is totally perfect, if the wind is slow or absent, and the wind happens to make the exhaust gases drift past the air inlet for the A/C (for example the wind blows slowly as a gentle breeze from the back to the front of where you are parked), then you will get Carbon Monoxide entering your car.

The millions of taxi cabs and police cars at idle - they are awake, so, they will smell exhaust gases and do something about it instinctively, if there is a problem.

If police officers slept in their cars at idle ....... ...... Anyway, when you are asleep, you can't actually smell things. You can't even smell smoke. If your house catches on fire, you will only wake up when you feel pain (due to your skin being burnt), but by that time, you will be in a deadly situation, and will have probably breathed in so much carbon monoxide / toxic gases that you can't actually wake up. This is advertised by the New Zealand Fire Service - most people don't have fire alarms (even mine have run out of batteries). Without a fire alarm, a house fire is probably deadly if you happen to be asleep (note : the sense of smell is 'older' than the sense of hearing, so hearing can wake up the brain if there is a loud noise but 'smell' is basically 'switched off' when you sleep.)
-> Also, carbon monoxide itself does not smell at all.

The amount of gas you used is a lot more than if the car was in 'normal' mode. Have you tried applying the parking brake 'tight'? The jerking when the engine stops and starts is more likely to wake you than the noise?. However, the amount of gas is cheap, so it is a good way to get through the summer (if you have a carbon monoxide detector!) if needed.

I agree about not having AC overnight in hot countries / states / areas. I myself am going to convert my Prius into a two-seater 'stealth camper', for urban camping to tour areas of the country that don't have decent campgrounds, and have the hotels full or not-available. I hate being too hot - so much so that I have decided that I am going to get a 'Hiace ZX / Jumbo' to make into a reliable campervan; I will try to get a Prius drivetrain into it, but if not, I will literally get a Nissan Leaf (crashed, write-off), and move the battery, recharger, and aircon units into the Toyota Hiace Van. This would allow recharging anywhere including EV fast charging, and allow air con (and anything high-powered) to run overnight, for a few days in the wilderness.

Finally : PLEASE! get a Carbon Monoxide alarm.

Sources : I work in healthcare and I have seen what carbon monoxide (CO) poisoning does. CO is very reactive, so it 'sticks' to your red blood cells (Hb) and is almost impossible to remove. Your red blood cells take about 3 months to turn-over. If you are exposed to too much CO, it will keep building up in your blood, and make you slowly suffocate over days / weeks / months.

Additional source. I have seen what happens when someone gets CO poisoning, and survives. It can be OK, but it can result in something very, very bad. Something which makes you totally healthy for 2-3 weeks after the event, then develop a syndrome over a few weeks. It can make you 'dead man walking'. It can mean that you can have one bad night with a gentle breeze in the wrong direction, wake up with a mild hangover, and otherwise feel fine. Then you will, in a few weeks, be admitted to medicine, then neurology, then intensive care, then brain death (because CO can cause the brain to 'die', although the damage takes a few weeks to show, so you can get brain death while alive, then experience hell on earth until you enter a coma).

 

It’s not maintenance mode it’s called inspection mode. Engine idles endlessly it charges the battery and it cautions you to not drive as the traction mode is disabled in inspection mode and you could over rev the mgs.

Youtube vid called

Prius inspection

Shows you how yo get into it.

This car has extremely low emissions and should be ok but still a good idea to get an alarm since the cars engine will run endlessly.