Do Not Sell My Personal Information Jump to content


Radio / Accessory Mode


Meaty
 Share

Recommended Posts

I normally spend my lunch break in my car and like to listen to the radio whilst doing so, but is there any way to adjust the auto shutoff after 20 minutes?  Alternatively, can I press the power button for another 20 (and then another) without flattening the 12v Battery?

Link to comment
Share on other sites

The 12 volt Battery in the CT is the same as in the Prius rated at 45 AH (amp hour) capacity and as such is quite small. The only safe way to sit listening to the radio for extended periods is to put the car in ready mode. This way the high voltage Battery keeps the 12 volt Battery on charge. The car will use very little fuel while stationary just enough to keep the engine warm.

Fitting a higher capacity Battery would also overcome the problem, but the only available batteries of a physical size that will fit are mobility batteries for invalid scooters. These are AGM ( absorbed glass matt) batteries the same type as those fitted in the car but are rated at 60 AH.

I ran one of these batteries in my Prius, and now use an even larger one in my Lexus GS450H rated at 120 AH capacity.

John

  • Like 1
Link to comment
Share on other sites

You can press it again for another 20 minutes. I regularly do this, but I haven't tried more than one extra 20 mins at once. I presume if the Battery got too flat it would not let you keep doing it. Anyway you should probably wake up and go back to work after 40 minutes or so.

  • Like 1
Link to comment
Share on other sites

I should have added to my post above the Panasonic Battery fitted as OEM does not stand up well to being discharged, and there is no safety cutoff. A flat or low 12 volt Battery gives rise to all sorts of strange fault messages when turning the car to ready mode, and jump starting can and does cause serious expensive electrical problems particularly if the jump leads are reversed even for a split second.

All this is well documented on the Prius forums on which the CT is based.

John

  • Like 1
Link to comment
Share on other sites

20 hours ago, Britprius said:

I should have added to my post above the Panasonic battery fitted as OEM does not stand up well to being discharged, and there is no safety cutoff. A flat or low 12 volt battery gives rise to all sorts of strange fault messages when turning the car to ready mode, and jump starting can and does cause serious expensive electrical problems particularly if the jump leads are reversed even for a split second.

All this is well documented on the Prius forums on which the CT is based.

John

Jump starting anything incorrectly causes many electronic issues. The trick is check , check and check again to make sure you get it right. It is , however a very very simple thing to do if you can read the owners manual and follow the simple instructions. Starting a CT200 or any other Toyota derived hybrid is just a case of getting the on board computer start up. You don't actually jump start the engine. The on board computer starts up the engine on the HV system once it has started itself up on the 12volt system. So unlike starting a conventional set up with a flat Battery, you just need to draw enough power in order to fire up the computer. Reversing polarity trashes a lot of electronic circuits unless they happen to be protected ( they are very rarely protected).

  • Like 3
Link to comment
Share on other sites


It is not just reverse polarity that causes problem, and lets face it even the experts can get it wrong. Again going to the Prius forums will show just how many people get this wrong. The fewer jump starts done is fewer possibilities of getting it wrong. Sometimes for whatever reason we are late or in a hurry the weather is lousy, and it's throwing it down with rain the very time when things go wrong.There are other problems.

Many people insist on running the engine on the car that is providing the "jump" this is a definite no with the hybrid with normal alternators giving out very spiky supplies. A much better solution is a small jump pack carried in the car or better still carry jump leads protected against reverse polarity. This is cheaper than the fuse in the Battery terminal.

The other definite no is jump starting another car from a hybrid again because of the fuse in the positive Battery terminal. The Panasonic AGM Battery is also not designed for engine cranking. The owners manual also tells how to jump start from the terminal in the fuse box at the front of the car. This is fine if your jumping the hybrid, but not if your jumping another car. Why Toyota/Lexus did not put a diode at the jump point to protect the cars electrics is beyond me. The cost would be minimal.

The 12volt Battery does other things apart from booting up the computers before you even touch the start button. Opening the drivers door starts up the hydraulic pump for the brakes. Pressing the start button then boots the various ECU's, and these interrogate many sensors on many different systems a low voltage or missing return signal causing an error, and failure to go to ready. 

John 

  • Like 2
Link to comment
Share on other sites

Thank you all for such comprehensive answers (with the exception of cutting short my lunch and going back after 40 minutes of course), and I didn't realise it was such an issue as previous cars (my last being a Hybrid Jazz) have had no problems at all.  I'll try leaving it in 'Ready' mode and see how it goes. 

Link to comment
Share on other sites

as already said its best if its left in ready mode ,when the Battery starts to get low the engine will cut in for a few minutes and recharge the 12v Battery

then cut out, you know you will always be ready to go next time you get in.

 

 

Link to comment
Share on other sites

21 hours ago, Britprius said:

It is not just reverse polarity that causes problem, and lets face it even the experts can get it wrong. Again going to the Prius forums will show just how many people get this wrong. The fewer jump starts done is fewer possibilities of getting it wrong. Sometimes for whatever reason we are late or in a hurry the weather is lousy, and it's throwing it down with rain the very time when things go wrong.There are other problems.

Many people insist on running the engine on the car that is providing the "jump" this is a definite no with the hybrid with normal alternators giving out very spiky supplies. A much better solution is a small jump pack carried in the car or better still carry jump leads protected against reverse polarity. This is cheaper than the fuse in the battery terminal.

The other definite no is jump starting another car from a hybrid again because of the fuse in the positive battery terminal. The Panasonic AGM battery is also not designed for engine cranking. The owners manual also tells how to jump start from the terminal in the fuse box at the front of the car. This is fine if your jumping the hybrid, but not if your jumping another car. Why Toyota/Lexus did not put a diode at the jump point to protect the cars electrics is beyond me. The cost would be minimal.

The 12volt battery does other things apart from booting up the computers before you even touch the start button. Opening the drivers door starts up the hydraulic pump for the brakes. Pressing the start button then boots the various ECU's, and these interrogate many sensors on many different systems a low voltage or missing return signal causing an error, and failure to go to ready. 

John 

Experts who get it wrong clearly aren't experts are they?There is a word for an expert who  isnt. Opening up the door does nothing if the Battery is flat. Please read. you cant jump start a toyota derived hybrid. All you have to do is give it a 12 volt feed. You can easily do this from another car, you just don't start the engine on the other car because you wont be drawing a high current so its no use in subjecting the hybrids electronic sensibilities to the dirty power which comes from some vehicle alternators.

I have started both my prius and my Lexus CT from a flat Battery a number of times. It is very very simple indeed. There just is no way to start another car from a Toyota derived hybrid but there is a way to start a stranded vehicle either by pushing it or by applying the small booster Battery which I carry when I will be leaving my car for prolonged periods in long stay car parks. Maybe the reason I dont have a problem is that I do it all by myself. IE I connect to the remote Battery terminals, I then take the time to check that the power connections are not going to fly off if the engine fires up, Next I cancel the alarm which quite often announces that someone has opened the door without disarming the alarm. Next I go and sit it the car to start it as usual.... so there is always a minute or two between connecting up a power source and trying to start up. Having fired up the computer, the engine generally starts  quite quickly afterwards particularly in cooler weather.   There really isn't anything very complicated..the technology involved with this sort of thing is 30 years old or more...unlike other aspects of the same vehicle. but there again I have a lot of engineering experience, so i would say that i guess. 

 

 

  • Like 1
Link to comment
Share on other sites

Wass, I am a retired electronics engineer, and was involved with the original Toyota hybrid system. The Toyota Hybrid will start another car, but it is by no means a good idea to do this. Show me someone that has never made a mistake, and I will show you someone that's not telling the truth. These things happen. I am not saying it is not simple, but I am saying it is fraught with dangers.

Opening the drivers door puts a load on the 12 volt Battery that increases to over 40 amps for a short period. The so called boot sequence adds over 20 amps more.

John.

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share



×
×
  • Create New...