Engine started to protect system ev driving unavailable

[Steve169]

Got this message today, disappeared, then came back later on. 

Anyone had anything similar? 🤔 

[philip42h]

It features in the Owners Manual:

􀁑 If “Engine Started to Protect System EV driving unavailable” is displayed on the multi-information
display 

EV driving may be canceled in order to protect the hybrid system, etc. In this case, perform driving with the gasoline engine until EV driving will be returned to automatically.

 

It doesn't make it seems like anything to worry about ... 🙂

Edit: PHEV only - not there on a HEV

[Dippy]

Anything to do with running the traction Battery down?

[Steve169]

Doing it when it's pretty much fully charged 🤔

[ernieb]

Normal, occasionally the ICE will fire to run the fuel, oil etc., around the engine. It will also fire even with a full traction Battery if you select front windscreen demist, braking heavily especially downhill but normally in these situations will not show the message.

[Steve169]

Yeah, it's ran fine for a year. Once that message appears I've never seen it go back into EV till the car has been off for a bit 

[philip42h]

I imagine that you'll be taking it to the dealer for an explanation?

Guessing, I imagine that it could be due to the front electric motor getting over warm. If that were the case:

• It would never occur on a HEV since the traction Battery is too small (and the front electric motor too weak) for MG2 to be running for an extended period.
• It would only occur after you have been running for a while and, most likely, 'pushing along' in EV mode?
• It would automatically recover once the car has had a rest and the motor a chance to cool down.

But that is more guess than hypothesis ... 😉

[Steve169]

It's happened a few times, with no real pattern and in the first couple of miles of driving. Then after I'd stopped for five minutes, didn't appear again.

[richie69]

Am I wrong, or isn't the transmission oil pump ran by ICE? If that's the case, Philips theory of MG2 getting (too) warm might explain this.

[philip42h]

14 minutes ago, richie69 said:

Am I wrong, or isn't the transmission oil pump ran by ICE? If that's the case, Philips theory of MG2 getting (too) warm might explain this.

You are correct for the HEV, but "The RAV4 Prime uses an external electric oil pump for use in EV mode" according to the addenda to Understanding the Toyota RAV4 Hybrid. So it shouldn't need to start the ICE just to circulate oil within the transmission.

[CBphev]

I had this today for the first time so thought i would note down the circumstances / history for info for others when it happens.

Car has done 8300 miles, this has never happened before, engine has fired up when really cold outside or hard acceleration when SOC is lower or demist is on etc - but that doesnt generate the message. 

Electric range about 30 miles, 5degC, petrol filled 2 days earlier from near empty with premium petrol.  Wasnt driving hard, engine just started when in EV mode and got the message.  Drove to work on engine power.  Probably hadnt run the engine for a week  - not unusual for me and it often goes for 2-3 weeks driving electric only.

Turned car off and back on when i got to work - engine started with same message.  Turned off and left the day.  Went to go home 10 hours late and engine fired upa gain with the same message.  Drove home, then went for a good blast up and down the dualler, making sure plenty of power action!  One thing i noticed was that the car was still working as a hybrid with the info screen showing power from the motors to the wheels and no loss of peak power.  After 15 mins of hard work, turned car off when i got to the shop, bought some wine (to drink whilst writing this), then car ran on electric with no message.

I get that this is normal but i would be keen to understand why it decided to exhibit this normal behavious and show the message today - I will monitor to see how long till it happens again - hopefully not for 8000 more miles!

[Steve169]

I had it approx five times in a few days with no real pattern, but now nothing for a week or so 🤔

[nlee]

Pure speculation but I wonder if this could be anything to do with the particulate filter cleaning cycle. Similar to previous diesels, if the cleaning cycle starts but the drive isn't sufficient to complete, it keeps restarting on subsequent journeys to complete a cycle. Once it's had a good blast it returns to normal?

I've never had this but do 100+ mile trips a couple of times a month.

[Yugguy1970]

Aye, I agree.  Even though the Atkinson engines are designed for efficiency and for stop/start behaviour, they are still internal combustion, and any IC engine can coke up if it isn't heated up properly every now and then.

[CBphev]

1 hour ago, nlee said:

Pure speculation but I wonder if this could be anything to do with the particulate filter cleaning cycle. Similar to previous diesels, if the cleaning cycle starts but the drive isn't sufficient to complete, it keeps restarting on subsequent journeys to complete a cycle. Once it's had a good blast it returns to normal?

I've never had this but do 100+ mile trips a couple of times a month.

Seems a plausible scenario, I don't often do long journeys on petrol so it wouldn't get tondo a cycle often, I ma normally limited to 20-30 miles.  

 

[zmsg]

Could this issue or warning from not using gas for a long period of time and the computer/sensor wanted to fire up the gas engine to burn off stale gasoline? This happened a couple times on my wife's RAV4 Prime last few weeks and the outside temp is colder. This never happen when the weather was warmer. She use EV most of the time. She charge her RAV4 before going to work and charge it up at work before returning home. She use Auto mode, so the engine only turns on when the car needed more power to go up hill or passing other cars. I just have a 10K service on the car, a few weeks ago right before these pop up message appears, and they told me everything was ok. I call the Toyota service last week, sounded like they have no clue what this pop up message mean. If Toyota Engineering is reading this message trail, they should comment on this, so everyone can get a better answer on what casused this pop up message.

[TonyHSD]

Well, I think we have the correct answer here between the posts if we star read from the beginning. In normal hybrids the engine kicks in for two main reasons except driving the car and for heating  : 

1. Charging the battery 

2. Discharging the battery 

I believe it’s number 2 from above. Nothing to do with particulate filter or overheating mg2. Particulate filter barely needs cleaning in petrol cars and mg2 has its own coolant and oil for maintaining temperature plus when vehicle in motion the wind chill helps too. 👍

 

 

[Steve169]

Still never been on again since 

[CBphev]

On 1/27/2023 at 10:16 AM, CBphev said:

Seems a plausible scenario, I don't often do long journeys on petrol so it wouldn't get tondo a cycle often, I ma normally limited to 20-30 miles.  

 

Well car did it again this morning, so didnt do it for the first 14 months of its life and now does it every few weeks - SOC was about 10 miles range, petrol half full and was filled up 3 weeks ago (in its first 14 months I have had 8 weeks before fill ups and this didnt happen), 5degC so not particularly cold.  

There is no common theme that I can identify for this apart from its !Removed! annoying!  Makes me feared for charging the car at work in case it ends up fully charged but not using the Battery for days.

Still, I could speak to my local toyota dealer but they are 9 weeks till they can fit it in for a check and software update as they only have 1 hybrid trained tech! 

[ernieb]

Chris, I wouldn't worry too much frankly, it seems to me that the car has all manner of reason it wants to start the ICE, hard acceleration, front screen heater on, decides it's time to cycle the engine. I've had mine fire with a full traction Battery and at the time could not figure the reason but it went back into it's more predicable cycle after a few miles. 

I've also hit the EV/HEV mode button instead of the brake hold button when I was wearing gloves. I'd just drive the car as usual and charge as required and wait till it goes in for a service, making a note if it should fire the ICE more regularly.

[Nick72]

I think what we need here is an explanation on the display... Engine started because... 

Surely something as simple as this would save a whole lot of dealership visits and phone calls. Save Toyota money.

[nlee]

Engine started because..... It's protecting the system? 😄

[Steve169]

Mine has randomly done it again once a couple of days ago

[TonyHSD]

But there aren’t any errors or warnings yellow triangles to be worried about and contacting the dealer. The car simply does it’s own things and it’s letting you know with the message displayed  as per the op picture.
Every hybrid driver do get similar notes on the dashboard at some point even on non plug in models. I had at least 3 different messages about ev mode unavailable because of something. Nothing wrong with the car and all it’s good.  
Only if you get ⚠️ This warning symbol and red warning lights ⛔️ then should not drive , check manual and call a dealer eventually. 
Whatever is the reason it is good that the car has used the engine to protect the Battery as it does in all hybrids even from early hev models. Most likely something with Battery temperature management or charge levels. 👍

[Nick72]

On 2/16/2023 at 9:56 PM, Steve169 said:

Mine has randomly done it again once a couple of days ago

I'm wondering if the slope the car might be parked on has any bearing on this? My thinking is there are probably several transducers in the engine monitoring temperature, oil pressure, strain and more. If the car is parked on a slope it may result in say the oil pressure sensors getting an odd reading so the car thinks it needs to start the engine to get the fluids circulated. This may not be engaged right away but after some initial delay.

 

Long shot I realise but it is peculiar that a number of folks get this message when others don't. Must be something that correlates for those that do and don't? Just don't know what that is.