2017 Tacoma AGM dual battery charging issues

Jaysonn

New member
Currently running an IBS dual battery setup with 35PC1400 odyssey batteries in my tacoma and am currently having issues keeping my batteries charged properly.

I understand that the 3rd generation tacoma has a smart alternator and doesn't put out adequate voltage to the batteries. On previous generations you could boost the voltage via plugging a voltage booster in the alt-s fuse under the hood but toyota has changed it up and is now using the ECU to control the voltage regulator.

My one draw currently is a 35 qt engel fridge on the service battery and i have a dash cam on my starter battery when the truck is parked.

I am currently looking at the ctek 140a offroad but i am unsure if this is the right choice. I plan to keep both batteries under the hood of the truck. I have not decided where i would mount the 140 if i go that route but i am open to better options.

Truck gets drove 2 hours a day and the vehicle is parked in a underground. During the day at work i can plug in if i add some sort of shore power,solar, or both.

I do alot more driving off grid but i am still worried about the batteries not getting 14.7 volts

Thanks
 

jeffjeeptj

Adventurer
Would you consider putting a factory style battery back in place and using a dc to dc charger to charge the two Odysseys Placed some place else?
I have a 2003 Sequoia with the diode in the alt-s location and still did not get enough power to charge an Odyssey PC2150 (group 31) sufficiently thru a Bluesea ACR and 1/0 cables to the Grp 31 In the very rear of the Sequoia.
The problem got solved when a couple of changes got made. 1. I put a Renogy 20Amp dc to dc charger between the engine battery and the second. I did move the battery from the rear of the Sequoia to the footwell behind the driver’s seat. I also reduced the cable size from 1/0 to #8 for the input to the Renogy. Its even better now, with a Battleborn in the second battery location and the dip switches on the dc to dc changed for the lifepo4. You’ll see a battery box in the footwell, a bit of Renogy and part of an ARB fridge. 2. for a starting battery I have a Northstar Grp 31 AGM which the Sequoia likes a lot better than the Odyssey I had there previously. The Sequoia would not fully charge the Odyssey Grp 31 engine battery by itself, nor a PC1700 by itself. About once a month, I had to disconnect the engine battery and charge it using an Odyssey 50amp charger. I also saw only a 7 year life with the pc1700 and no external charging. In 2004 I installed a pc1700 (7 year life), replaced with another pc1700. I got into dual batteries in 2013 when I put a pc2150 in front and in back. Now I see a sufficient charge to the Northstar and have not seen the need for an external charge.

For shore power Iuse an IOTA DLS-55 with and IQAGM dongle. The Odyssey pc2150 likes that.

oh, be careful of external charging with battery connected to the vehicle. It may be coincidence, but, the first and only time I did not disconnect when external charging, three sensors had to be replaced the next time the car was driven. I went out of town right after charging, wife needed the Sequoia a couple of days later. She was not impressed with “CEL, VSC off, and VSC trac all lighting up” and took it to dealer for service. I don’t remember what they replaced, but it wasn’t cheap.
 

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Jaysonn

New member
Would you consider putting a factory style battery back in place and using a dc to dc charger to charge the two Odysseys Placed some place else?
I have a 2003 Sequoia with the diode in the alt-s location and still did not get enough power to charge an Odyssey PC2150 (group 31) sufficiently thru a Bluesea ACR and 1/0 cables to the Grp 31 In the very rear of the Sequoia.
The problem got solved when a couple of changes got made. 1. I put a Renogy 20Amp dc to dc charger between the engine battery and the second. I did move the battery from the rear of the Sequoia to the footwell behind the driver’s seat. I also reduced the cable size from 1/0 to #8 for the input to the Renogy. Its even better now, with a Battleborn in the second battery location and the dip switches on the dc to dc changed for the lifepo4. You’ll see a battery box in the footwell, a bit of Renogy and part of an ARB fridge. 2. for a starting battery I have a Northstar Grp 31 AGM which the Sequoia likes a lot better than the Odyssey I had there previously. The Sequoia would not fully charge the Odyssey Grp 31 engine battery by itself, nor a PC1700 by itself. About once a month, I had to disconnect the engine battery and charge it using an Odyssey 50amp charger. I also saw only a 7 year life with the pc1700 and no external charging. In 2004 I installed a pc1700 (7 year life), replaced with another pc1700. I got into dual batteries in 2013 when I put a pc2150 in front and in back. Now I see a sufficient charge to the Northstar and have not seen the need for an external charge.

For shore power Iuse an IOTA DLS-55 with and IQAGM dongle. The Odyssey pc2150 likes that.

oh, be careful of external charging with battery connected to the vehicle. It may be coincidence, but, the first and only time I did not disconnect when external charging, three sensors had to be replaced the next time the car was driven. I went out of town right after charging, wife needed the Sequoia a couple of days later. She was not impressed with “CEL, VSC off, and VSC trac all lighting up” and took it to dealer for service. I don’t remember what they replaced, but it wasn’t cheap.

I appreciate the info. When i first decided on the setup and did my research i didn't do enough. I had no idea agms required 14.7 volts. Now 2 and a half years later i am starting to see the issues arise. I have pulled my service battery out and am now trying to desulphate it then swap the starter and service every week with a proper charge from a agm charger.

You mentioned issues with external charging with the batteries hooked up. Was that before or after you started using the IOTA DLS 55 and dongle?

Seems these newer vehicles are getting more and more sensitive and i don't want to start frying ECU's from shore power.
 

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jeffjeeptj

Adventurer
The loss of sensors MAY have been coincidental. I used an Odyssey OMAX charger, which took batt voltage to 15.3 for a short time. Since then, I have always assured any batt I was charging was isolated from the car, including when I use the Iota. I’ve lost no sensors since that one time (about 5 years), but I’m taking no chances. The Iota with AGM dongle will put out 14.7 volts, never more, and is very clean power, Then drop to 13.6. There is a technical paper you can find on the Iota site about each of their dongles. One reason I like the Iota is the selection of dongles.
on a side note, Battleborn does not like the Iota charge curve, but, I’ve been using the Lifepo dongle when I charge the BB battery on the bench and have had no problems.

have you read the Odyssey “recovery” process document? It is in the Odyssey site. Basically discharge to 10.0 volts and then do a full recharge. The document states You can do this a few times (I have) and the battery should improve. Reminder - Odyssey does not like “equalization”.
 

jeffjeeptj

Adventurer
I’ve not had an Odyssey 1500 so this comment may not apply. The 2150s and 2250 Were hard to charge. The batteries liked to stay at 14.7 volts for what seemed a long time. If you did not keep pushing the amps in at 14.7 for a long tome, you would get a Partial State of Charge, which is what you are dealing with. With your sulfate condition.
There are other threads on here about this. Do a search on Sears platinum, duckysdad, and odyssey. duckysdad
is the reason I bought a Northstar.
 

Ducky's Dad

Explorer
The 2150s and 2250 Were hard to charge.

Understatement of this young year. I have three big Odyssey chargers (40amp three bank, and two of the newer 25amp units) and never had good results with them on my 2150s. I switched out my Odyssey and Optima batteries on the PW, and installed V-Max AGMs. Also switched over to a Ctek 25amp charger, added a kill switch to the starter battery to disconnect it when the truck is parked for long periods. Getting much better results with this combination. All while the Northstar G31 in my Tundra with stock charging system has never needed a lick of attention.
 

jeffjeeptj

Adventurer
My 50 amp three bank works well (I think) if I use it as a single bank. The “auctioneering” of the battery charge when more than one battery is connected really takes its toll on charging properly.
i have followed the Odyssey “recovery” plan by dropping the batt voltage to 10.0 using an H4 headlamp (approx. 5A draw) on my bench, then recharging. When the Odyssey charger is at 50 amps for a period of time, the cables and clamps get too hot too touch. The battery case will warm, but, I can hold my hand on it anywhere except the terminals due to the clamps. I have started using an Iota DLS 55 with IQ-AGM dongle that I like better than the Odyssey. Especially since I use 4 gauge wire (4 feet long) with lugs attached to the studs. A lot less heat At the terminals.
I put the Group 31 Northstar in the Sequoia as an engine battery and use the alt-s diode voltage booster. Works well, even on a trip to Florida (2 days, 7 hours each). Northstar has been installed since mid-October, and starter likes it. The Northstar will drop to 13.5V after a 7 day rest with normal Sequoia parasitic drain.

i just cannot bring myself to scrap the Odysseys as they still have some life in them. One has a 2012 date sticker, a 2nd has a 2014 date, 3rd date code is gone, but older. I have spent a fair amount of electricity keeping them conditioned. The 2014 battery actually behaves the best. It is in my Travel Trailer. I left the trailer stored for 15 days with battery disconnected, came back, hooked up the ground, and it actuated the electric tongue jack just fine till I got the TT parked in my camp spot. When I left the TT, i had used the electric jack to unhook from the Sequoia, so it was left in a slightly discharged condition for those 15 days. Now sitting with a 2nd Iota float charging at 13.58V while wife and I play “snowbird”.
 

Ducky's Dad

Explorer
I tend to keep my old batteries unless they are completely toasted. They are handy for low-draw loads like testing landscape lighting and 12v pumps, and it's nice to have cores when the battery dealer wants to charge an extra $15 if you don't leave your old battery. My current maintenance routine on the PW with three V-Max AGMs is pretty simple. I hook up the Ctek 25-amp to the starting battery with the kill switch disconnected and get that battery topped off and sometimes conditioned, then the next day I manually switch the two house batteries into the charge circuit and top them off. The three batteries combined are about 254ah, so absorption charge takes a while, but the strategy seems to be working.
 
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