Toyota: advice on 12v battery maintenance

[loz8]

"would happen in any car" not so,you would disconnect one terminal.Did this for 6 months of the yr for nearly10 yrs,battery kept charge on a diesel.

[Hadrian1]

Our first hybrid was a Honda Civic.  The was a sticker on the underside of the bonnet saying "This car must be run for at least 30mins every month" ..  The 12v Battery on our Lexus hybrid went flat, so much so that it wouldn't take a charge until I used another Battery to put a few volts into it.  Then even when fully charged it didn't last long before I had to replace it.

[50p]

Hi, first post, hopefully in the correct place!

Collecting my 'new to me' 2020 Corolla on Tuesday. Must admit to being somewhat concerned regarding all the 'flat battery' reports. The advice given is fine during normal circumstances, just drive the car, trickle charge when not using the car BUT what about leaving it for 2 /3  weeks in an airport carpark? Is the car likely to start .. guess it would be worse going on holiday for that length of time when it's cold here!

Any comments / ideas / suggestions wecomed (apart from not going on holiday)

[Parts-King]

4 minutes ago, 50p said:

Hi, first post, hopefully in the correct place!

Collecting my 'new to me' 2020 Corolla on Tuesday. Must admit to being somewhat concerned regarding all the 'flat battery' reports. The advice given is fine during normal circumstances, just drive the car, trickle charge when not using the car BUT what about leaving it for 2 /3  weeks in an airport carpark? Is the car likely to start .. guess it would be worse going on holiday for that length of time when it's cold here!

Any comments / ideas / suggestions wecomed (apart from not going on holiday)

If you are using the car regularly and putting miles on it, you should have no issues. i do 40 miles a day, and when I was off work for two weeks with Covid, thinking about the Battery was the last thing on my mind. It started perfectly after two weeks standing 

[Roy124]

Agree, during the first lock down my car was little used.  I took delivery on 1st March last year.  No problems and I had not even heard of the need to run the car.  The problem only arose later possibly through something being left on or a charge deficit building up.

As I have said, the Battery failed a test and was replaced by one of greater capacity.  Whether this was a one-off by the garage or Toyota has changed the spec I don't know.  Mine was 45 amp/hr and the new one 52 amp/hr.  Interesting to see what you have got.

After my experience I remain wary and will monitor the Battery over a few days when the car has not been used.  Its first big test will not be until next March when we are away for 2 weeks.  As it will be airport valet parking it wont be my problem!  However I think a good Battery should last that time.

[TonyHSD]

Summer time with Battery in good shape no problems 4 weeks to be left, winter time not sure, never been on long holidays in winter time. If the car been in regular daily use prior to the holiday might survive during winter for 2-3 weeks , perhaps solar charger maybe useful. 

[PAISLEY1903]

would something like the NOCO GB20 work or would I need the GB40.  

[Roy124]

3 hours ago, PAISLEY1903 said:

would something like the NOCO GB20 work or would I need the GB40.  

Craig, I don't know what engine you have but have a look at this site which gives you a comparison:

Compare Best NOCO Boost Jump Starters: GB20 vs. GB40 vs. GB50 vs. GB70 vs. GB150 - Top Product Comparisons

In my case, with a hybrid and 12v Battery that does not have to drive a starter motor I have opted for a very small booster that I hope will do the job.

[robo1]

I’ve just bought the Noco GB20 just in case. According to the Noco website it recommended for gasoline engines up to 4 litres. As ROY124 has just written the booster does not have to power the starter motor it just needs to power up the electronics so should work fine. 

[Roy124]

I have an ancillary question.  As I related somewhere, my 45 amp/hr Battery was replaced with a 52 amp/hr one under warranty.  Essentially I am looking for a comparison with 2021 1.8 Corolla; what size Battery is standard on the 2021 model?

[PAISLEY1903]

5 hours ago, Roy124 said:

Craig, I don't know what engine you have but have a look at this site which gives you a comparison:

Compare Best NOCO Boost Jump Starters: GB20 vs. GB40 vs. GB50 vs. GB70 vs. GB150 - Top Product Comparisons

In my case, with a hybrid and 12v battery that does not have to drive a starter motor I have opted for a very small booster that I hope will do the job.

thank you @Roy124 its the 2.5 petrol hybrid. Thank you for that the videos I have seen online seem to use the GB40 for some reason.

[PAISLEY1903]

4 hours ago, robo1 said:

I’ve just bought the Noco GB20 just in case. According to the Noco website it recommended for gasoline engines up to 4 litres. As ROY124 has just written the booster does not have to power the starter motor it just needs to power up the electronics so should work fine. 

Thank you @robo1 the GB20 is cheaper than GB40 so that will do for me as well !

Is it a case of lift the fuse case, flip the red cover up and attach to there and the black to non painted part of car.

[robo1]

That’s it. The plate under the red cover has plastic on one side so you have to make sure the clip is attached to the metal. 

[robo1]

Roy. 
Not the answer to your question but my 2021 hybrid 2.5 litre RAV has a 45 amp/hr Battery fitted so would expect the 2021 Corolla to have similar

[Roy124]

Robo, I would guess that is the case then.  Provided the 12v standing loads are the same or very similar they obviously think 45a/hr is adequate. 

[PAISLEY1903]

Thank you @robo1 my Rav is on order so can't check it but I noticed the cables on the GB20 look quite short. Where are you placing the black one. 🙂

[robo1]

There’s are some  nuts used to anchor the shock absorber close to the fuse box.  Using a multimeter they do show they are grounded. The leads are long enough for this. Other option is to connect to Battery which is in the boot on the right side.
Never had any problems with my Previous RAV hybrid and hopefully will not need to use the booster but like to be prepared.

[Catlover]

1 hour ago, robo1 said:

Never had any problems with my Previous RAV hybrid and hopefully will not need to use the booster but like to be prepared.

Be aware that over time the booster Battery may loose its charge, so, if you don’t check it regularly, especially in cold weather, and you come to use it there may not be enough charge in it to start your car. 

[PAISLEY1903]

2 hours ago, robo1 said:

There’s are some  nuts used to anchor the shock absorber close to the fuse box.  Using a multimeter they do show they are grounded. The leads are long enough for this. Other option is to connect to battery which is in the boot on the right side.
Never had any problems with my Previous RAV hybrid and hopefully will not need to use the booster but like to be prepared.

thank you very much

[PAISLEY1903]

2 hours ago, robo1 said:

There’s are some  nuts used to anchor the shock absorber close to the fuse box.  Using a multimeter they do show they are grounded. The leads are long enough for this. Other option is to connect to battery which is in the boot on the right side.
Never had any problems with my Previous RAV hybrid and hopefully will not need to use the booster but like to be prepared.

@robo1 do you think this would work with it https://www.amazon.co.uk/gp/product/B071F36LXZ/ref=ox_sc_saved_title_3?smid=A3P5ROKL5A1OLE&psc=1

[robo1]

If you choose that option you would have to hard wire it to the Battery in the boot. One problem is if your Battery has discharged the electric tail gate won’t open so you would have to get in via the rear seats either to attach your booster to the leads or open the tail gate manually. 

[PAISLEY1903]

9 hours ago, robo1 said:

If you choose that option you would have to hard wire it to the battery in the boot. One problem is if your battery has discharged the electric tail gate won’t open so you would have to get in via the rear seats either to attach your booster to the leads or open the tail gate manually. 

good thinking. I will stick to using the one in fuse box at front and attaching to the nuts that you mention. Without having the car yet I have seen a photo online that shows I think 3 nuts in close proximity ! 🙂

[robo1]

13 hours ago, PAISLEY1903 said:

good thinking. I will stick to using the one in fuse box at front and attaching to the nuts that you mention. Without having the car yet I have seen a photo online that shows I think 3 nuts in close proximity ! 🙂

Craig

The first photo shows the positive terminal with the cover in the open position. You can see there are a few grounded nuts to attach the negative clip to.

[robo1]

The official grounding point is 1 metre away on the left side of the engine. If I had designed it I would have put it on the right hand side!

[Roy124]

Is there a facility to hard wire the positive lead apart from on the Battery post?