Can't trickle charge the 12v battery

stangbat

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I'll reiterate what other have stated. I have a 1A trickle charger/maintainer hooked up to the same posts that you are using and it tops up and maintains the battery just fine. But I'm not running anything in the background nor do I have anything plugged in to the OBD port.

I'll also agree with not using a desulfator. They don't work, and I've twice had them kill diodes over time due to the voltage spikes they emit. I had to replace a diode on a battery backup sump pump control board that had a desulfator hooked up. And I had to replace the current sensor in my Honda Odyssey that had a desulfator hooked up. Could have been unrelated, but funny that since then I've never had any more problems.

And in both cases the batteries failed just like they normally would over time even with the desulfator hooked up. I learned my lesson. Desulfating might work under the right conditions, but for practical every day use they are snake oil.

Edit to add that I wasn't using the desulfators on AGM batteries. They were regular old school flooded lead acid batteries, which is what the desulfators should have been protecting.
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arebpierce

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I’ve found that a 16amp or better charger works the best, also do not use a desulfatotion on a battery connected to a car, disconnect first, newer desulfate chargers won’t activate if connection is sensed by the charger.
Don’t use desulfurization on a AGM battery. Or at least that’s what I have been told. It will cause the battery to off gas and eventually shorten its life.
 

djrmache

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Canā€˜t the 12 v battery be charged by clipping trickle charger alligator clips to the leads at the bumper access port?
 
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Nope, Alll those leads do when connected to a 12 volt source is open the Fronk.
 

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I use a 5amp charger and it keeps things topped up nicely provided the OBD2 port is inactive.
 


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PilotMark

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Recap:
With 1 amp trickle charger and ODBII plugged in running Torque lite the battery discharges faster than the 1 amp can charge it.
With a 10amp charger it chargers with the ODBII and Torque running.
Last night readings 12.5 v and 79% soc
removed odbii and turned off Torque (Ok it can't work without the adapter plugged in) and charged with 1 amp charger.
Reading this morning (12 hours) 12.6 v and 84% soc.

Findings:
running the ELM 327(may have that number wrong) and torque lite takes more than 1 amp.
Using a 1 amp charger you need to have no added drain and it will need to be on 12 plus hours.

Sub note: I've updated the ODBII to ODBLink MX+ arriving next week. I'll do a few more test then.

Thanks for the comments and sharing your Mach E knowledge
 

zvez

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Recap:
With 1 amp trickle charger and ODBII plugged in running Torque lite the battery discharges faster than the 1 amp can charge it.
With a 10amp charger it chargers with the ODBII and Torque running.
Last night readings 12.5 v and 79% soc
removed odbii and turned off Torque (Ok it can't work without the adapter plugged in) and charged with 1 amp charger.
Reading this morning (12 hours) 12.6 v and 84% soc.

Findings:
running the ELM 327(may have that number wrong) and torque lite takes more than 1 amp.
Using a 1 amp charger you need to have no added drain and it will need to be on 12 plus hours.

Sub note: I've updated the ODBII to ODBLink MX+ arriving next week. I'll do a few more test then.

Thanks for the comments and sharing your Mach E knowledge
thanks for the followup. DIscharging the 12v is why I absolutely never run the car in accessory mode, if I'm in it or doing things with doors open, it's powered up.
 

dtbaker61

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Thinking I'd like to occasionally charge the 12v battery or maybe even desulphonate the battery, I cut the holes found plugs and then it did not charge.
I have a battery minder trickle charger/maintainer.
The 12 volt was at 12.57 and 54%
I had an odbii attached and running torque on my android phone.
I noticed there was a difference between the torque reading 11.7v and the fluke (12.57) at the attach points.
The car is off and I took off the red cover on the + and attached the battery charger to the steel post then the copper under the red cap.
Over the next 30 mins the 12v went down to 47% charge with the car off and the charger connected.
I gave up for the night and plugged the car in and it started to charge the 12v battery within a min or two.

The battery minders are 12v 1 amp output. I use them on my ice cars and they have worked well.

What am I missing?

Do I need to use a battery charger not a maintainer?




Holes by 12v.jpg
Holes by 12v.jpg
you *should not* ever need an external charger/minder..... The BCM is programmed to wake up the MME and charge the 12v battery if and when needed, ans long as your HV SOC% >15%.

easy approach to occasionally, maybe once a month or at least once a quarter, desulf the 12v is:
- turn MME "on"
- settings>vehicle>auto-off = disabled
- leave MME on overnight, or up to 48hrs

this will hold the 12v at "charge voltage", and result in a fully charged and desulf 12v battery.
 
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PilotMark

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Thanks
 

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Honest to god there's a lot of bored people on this forum. Why on earth do you have to mess with the 12V?

It's been discussed to death now. If you don't drive it frequently enough it doesn't charge enough. Fine that's Ford's fault for making crappy software. They deserve all the criticism.
Buy a new battery and complain to Ford about it.
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