Charge 12volt battery using CTEK charger?

[Eddy James]

New owner…………

I have purchased a 2021 Yaris Excel and very happy with it. 

I have a CTEK Battery charger MXS 5.0 and have used it on other Hybrids l’ve owned to charge the 12v Battery because the terminals have been accessible. The 12v on the Yaris is mounted under the rear seat cushion resulting in the terminals now being inaccessible.

If the12v Battery goes flat I know you Jump start the car using the positive connector provided in the fuse box and ground the earth onto bare metal. Does this method imply there is a “direct route” to the 12v battery terminals therefore can I use my CTEK charger for the purpose of topping up the battery?

[Chippy01]

Access the Battery and fit a pigtail connector.

[hind]

12 minutes ago, Eddy James said:

Does this method imply there is a “direct route” to the 12v battery terminals therefore can I use my CTEK charger for the purpose of topping up the battery?

Yes

[Eddy James]

38 minutes ago, Chippy01 said:

Access the battery and fit a pigtail connector.

Thanks for the reply that was my "plan B" just wondering how easy it is to gain access to the Battery can't seem to find many Youtube videos

[hind]

It is rather difficult because there is very little space. 

[Eddy James]

2 minutes ago, hind said:

It is rather difficult because there is very little space. 

My thoughts too. I have seen an older video for Yaris MK2 with the seat cushion pushed out of the way and access to the terminals looked restricted. I don't want to have to remove the complete Battery to gain terminal access. 

[jthspace]

49 minutes ago, Eddy James said:

My thoughts too. I have seen an older video for Yaris MK2 with the seat cushion pushed out of the way and access to the terminals looked restricted. I don't want to have to remove the complete battery to gain terminal access. 

I did this . . . 

Bring the front passenger seat forward and incline the seat back (bring it sloping forwards). It will be clear later.

Grab the seat cusion about a foot inwards and tug like your life depends on it.  It will unclip but it needs spinich strength.

Repeat for the other side.

Get a broom and wedge the seat cushion up against the seat back, using the front seat to hold the broom (told you it would become clear!)

8mm spanner (from memory) to undo the black earth connector and tie the bugger back with some string or tape as it has a tendency to spring back and touch the terminal.

Undo the terminal on the red connector, your spanner will touch the seat support metalwork so make sure you've tied the neg terminal back as above.  Not on this car, but it's happened before and getting a welded spanner off is not easy as you watch smoke appearing.

Remove the nut and washer on the terminal posts and attach the fly lead. From memory, I think I managed to do this without loosening the Battery fixing plate, 10mm from memory.

I made mine long enough to reach into the boot as I preferred the charge lead to exit from the boot rather than the rear door.  Rubbers are pliable enoough that the boot/door will close without damaging the lead.

Reverse the terminal connections - red (positive) first then the black (negative).

Job done.

ALTERNATIVE

You can charge the Battery using the tab under the bonnet with the positive lead to the tab and the negative lead to an unpainted part of the bodywork (nut, engine - whatever the neg crocodile clip will reach).

 

[Eddy James]

Thank you. Interesting that you have done it although my Yaris is not a Yaris cross  which will be roomier inside.........food for thought

[jthspace]

3 minutes ago, Eddy James said:

Thank you. Interesting that you have done it although my Yaris is not a Yaris cross  which will be roomier inside.........food for thought

I did it on my Yaris and Yaris Cross - actually there isn't much of a difference in "working" room when you are bent over trying to undo the damned nuts in the space the rear doors dont give you! 🤣

[Kental]

On 11/6/2024 at 5:10 PM, Eddy James said:

Thank you. Interesting that you have done it although my Yaris is not a Yaris cross  which will be roomier inside.........food for thought

I removed a CTEK lead from our previous 2021 Yaris, when you remove the access panel along the front edge of the seat (instructions on this are in the manual) there is an accessible charge positive tab there with no need to lift the seat squab.  Not checked if the Yaris Cross has the same as the wife has not let me dismantle her new car yet!!!

[jthspace]

2 hours ago, Kental said:

I removed a CTEK lead from our previous 2021 Yaris, when you remove the access panel along the front edge of the seat (instructions on this are in the manual) there is an accessible charge positive tab there with no need to lift the seat squab.  Not checked if the Yaris Cross has the same as the wife has not let me dismantle her new car yet!!!

Interesting - my 22 Yaris had the NEG terminal under the removable cover and the POS was the other side of the Battery. The Cross is the same.  Some pictures on the web show the POS terminal nearer the door, so at some stage Toyota has made a change.

[Tommy X]

To make it easier to connect charger leads without completely removing the clamp nut I snip a piece out of the connector with side cutters, then you just need to loosen the nut enough to slide the connector in, crude drawing attached

   

[MikeSh]

1 hour ago, Tommy X said:

To make it easier to connect charger leads without completely removing the clamp nut I snip a piece out of the connector with side cutters, then you just need to loosen the nut enough to slide the connector in, crude drawing attached

   

You can also get connectors with the gap already there (I can't remember the name).

BUT ... in this application there must be a washer between the nut and the connector. If the nut has a washer already then make sure you fit the connector under the washer (with the nut on top). If there isn't a washer then leave the connector closed and take the nut off to fit. Clamping a nut directly onto an open connector almost always spreads the connector (they are usually soft copper) which opens up routes to places you don't want to visit.

[Eddy James]

Thanks every body for their responses. I have been hospitalized over the last 2 weeks and therefore been unable to reply and now at home making a full recovery.