connecting a CTEK charger
 

I keep our cars, especially those that don't get sufficient use, on CTEK charger/ maintainers and wondered if anyone else had wired up a permanent CTEK connection plug to their XC90 and if so, where?

I fitted a 12S socket to the towbar with a fused positive and a negative wire directly to the battery and if I don't use the car for a couple of weeks I connect the CTEK up for a few hours to top up the battery.

I believe it's possible to connect the CTEK directly to pin 9 positive and pin 13 negative of the 13 pin tow socket but that means it will be charging through the car circuitry and I didn't want to go down that route

I've made a solar charger using a cheap 10 w panel and an OBD2 plug off eBay and a controller I had kicking about.

This set-up conveniently gives an "always live" socket for phone chargers etc when parked up.. (I do road traffic surveys - You've seen us - Old guys in Hi Viz with a Thermos of coffee...)

I connected it to the OBD2 socket - pins 4 and 16 from memory

Just checked - Wow! I was right.

Works fine in terms of keeping the battery topped up and generates a small charge in daylight, stronger in direct sunlight obv.

The OBD2 socket is easy to use for temporary connections and is there already.

Cheers

Dave

You can connect the CTEK to the battery terminals in the boot or to the main power distribution box in the engine bay

The engine bay terminals will give you direct access to the battery with massive fat power cables that have absolute negligible voltage drop. That's where I connect.

I used to connect to the permanent live socket in the boot but found the socket got hot due to not very good connections and also it runs through the REM and a current monitor, so not a true battery voltage state.

As other's say, the permanent 12V and ground on the trailer socket is another alternative. The advantage of the 12V on the trailer socket is that it is fused on the REM

Thanks for all those ideas - unfortunately no towbar so can't use the towing circuitry. Probably will wire up one of those CTEK plug - in connectors directly to the battery in the boot just have to work out where to lead the electrical extension lead I use - with the BMW I used to just shut the door on the CTEK cable :speechless-smiley-5 but this Volvo seems to be somewhat more solid !! Not sure I want to be shutting the door on a cable this time!!

Looks like a great idea for other 12v applications

I do it all the time. There’s enough give in the weather seal for a cable to run through

I connected it up with the rear 12v socket temporarily until the CTEK attachment direct to the battery poles arrives via that big online emporium......seems to be charging up nicely, not too hot, but I agree direct to battery is much better.

Apart from my CTEK charger, I also have a CTEK Battery Sense, which gives you a fantastic view on your phone of the charge state of the battery, by grabbing battery data via Bluetooth. Just walk to within about 10 feet of the car, and the data is transferred.
This allows you to make an informed decision about when to add the battery charge to the car to top up the batteries.

As my car may sit for 3 or 4 weeks unused, I find it comforting to be able to quickly check and see what state the batteries are at.

Off to the garage now to update the status... 12.55V, 78% charged.

Swiss - on your recommendation I also purchased the CTEK battery monitor and overall I am happy with it.

I was a bit concerned though by the drop, almost every night, from 100% down to about 80%

A colleague tells me that it's normal for a secondary battery that the low(er) temps at night drop the terminal voltage but it seems to happen in a very precise way as if something was activating and drawing a constant amount of power for a fixed time??

One thing I have noticed is that the "every 5 minutes" reading on the graph isn't synchronised exactly to anything

Yesterday I saw a reading supposedly taken at 21:00 and it was only 20:30 or so

Do you know how to reset the clock in the monitor or does it do that when connecting to the phone?

I also found my car tried to connect to the monitor when I was testing the Bluetooth connection (to check if I could stream audio from the phone) which was interesting.

A good bit of kit though and I am looking forward to using it to monitor how effective the solar charger is going to be when we go to Spain for the winter as when we are there we don't use the car that much (we have elec bikes to get around on)

Cheers

Dave