Have had the Ctek for a year or so now but not yet used it on the 4.4, which has an agm battery.

I am going to give it a quick charge up through the trailer socket, as it has only done short runs recently, which is the best setting to charge the battery on? normal or agm?

Gut tells me Agm but I remember reading somewhere that the charging voltage was different? There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Which C-Tek model do you have?

MXS 7.0 has the AGM setting which charges at 14.7v There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Yes use AGM mode, it charges at 14.7V/7A.

Normal mode charges at 14.4V/7A

Recond mode charges at 15.8V/1.5A

 There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

I've been through the same thought process. I searched in vain for info on my Exide 90ah AGM battery charge rate.

I emailed Ctek and got a reply:

"Unfortunately, we've tried to find this type of info on Exide batteries
in the past to find the information available on web sites, etc lacking.
If you cannot confirm that the battery can accept a higher charge
voltage, it's better to use normal mode if in doubt, as AGM mode could
be damaging to an incompatible battery - but the reverse does not apply."

So, to be safe, I leave my Ctek MX 7 on 'normal'. I also use the trailer socket and although I've never charged from flat it works great at that setting for topping up and maintaining. Perhaps in mid-winter I might switch to AGM.

I'm pretty sure it will be ok either way. 2012 5.0L S/C
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