Battery Woes Compliant

[CTK59]

To the OP: were you being charged for battery/charging system diagnostics at the dealer any of the times you have brought it in, either with the factory batt or aftermarket?

Short answer - yes BECAUSE i have aftermarket battery.

 

[CTK59]

Got a OTA update yesterday that said something about improving battery charging in these trucks. Might ask them to manually do the update on your truck and see if it helps.

I had a constant issue with low charge on my truck. Even had dealer replace battery under warrant. I’m convinced the motorcraft batteries are trash. Upgraded with the biggest top of the line Interstate battery I could fit. Haven’t had an issue since.

Side note, that 775cca battery is actually pretty small for these trucks. The big interstates are like 950cca but the more important number is the 94 amp hour. Smaller AH ratings will drain much faster thus giving you low voltage. I’m assuming your battery is in the 70ah range which is drastically smaller. Put an Interstate MTZ H8 and don’t waste your time with the dealer.

Aftermarket was a X2Power, 840CCA, and 76AH and it lasted approx 6-mo before showing low charge and then no charge. As of yesterday, dealership says this battery will not hold a charge and has to be replaced before diagnostic testing can be done. Have to believe there isn't a parasitic draw ...

 

[CTK59]

Your dealership should be able to detect if there is something draining the battery.

You would think, right? Two trips last year w/OEM battery low charge and all they did (found out now) is charge the battery, now with aftermarket battery basically not holding charge, and I agreeing to new OEM battery they are going to do diagnostic testing - but, of course, I am paying for testing because I do not have the (original) OEM battery

 

[Keith88]

I’ve had 2 batteries warrantied by Furd. In my other cars I run the Wally World Everstart. If it happens again I’m puttin one in the Raptor.

 

[smurfslayer]

Short answer - yes BECAUSE i have aftermarket battery.

WRONG answer. The battery is a consumable, just like brakes. It doesn’t matter who makes it IF the component is good, you have a drain issue and that’s on the stealership to diagnose and troubleshoot, not you.

 

[jm77]

Aftermarket was a X2Power, 840CCA, and 76AH and it lasted approx 6-mo before showing low charge and then no charge. As of yesterday, dealership says this battery will not hold a charge and has to be replaced before diagnostic testing can be done. Have to believe there isn't a parasitic draw ...

Your original post said 775cca, I’m not seeing a 840 with 76ah but could be wrong. No matter the size of the battery these trucks are hard on batteries and driving habits will be a factor. Even with a large battery I place it on a trickle charger periodically, it’s actually good for the battery to get a full charge sometimes (the trucks won’t fully charge a battery).

I’d still bet getting the battery I listed will solve your issues. A battery lasting 6 months before showing low charge doesn’t seem like parasitic draw…

Another thing to look at, where are you keeping your key fob at night? Anywhere close to the truck? If the truck can detect it slightly, it will never power down.

 

[EricM]

Appreciate the comments, but at first they offered to put a new OEM battery in just to do testing/diagnosis, then reverse and said only if I pay for said battery. And yes BMS reset when I installed new battery, as far as OTA, I believe there are two at most. Hmm ... may have to try the interior camera suggestion - can't hurt.

Are you connecting the ground of your battery tender upstream of the BMS sensor?