BMS: The future is here...and it's awful :(

[s197richie]

Sounds like you need to go touch some grass.

I was actually out today; my friggin leak is back so I went walkin the rows at the yards and found a half-decent door weatherstrip at a fair price; swapped it in and also replaced some one-time-use only fasteners the screw threads weren't catching. I also attend car shows on weekends and hit the mall for a cinnabon and an eyeful.

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[tastetickles]

The BMS is there to prolong your battery's life due to the start/stop system, it tells the alternator when to pump out the full voltage for charging and when to lower it for trickle accordingly when your battery is being depleted. Indirectly this also prolongs your alternator's life.

The catch is when swapping new battery into the car, the new battery should be charged externally of the car especially when you car has dual battery setup, installed in the car and then perform a BMS reset so the car knows the battery is fully charged.

Alternatively one can connect up a new battery and then charge the battery by connecting up the red terminal as normal but the negative terminal from the charger should not be connected to the negative or ground on the car, it goes directly on the BMS terminal which is usually found on the negative side. This does run a risk of frying stuff as i noted voltage spike and drop when i open the door or doing something in the car, the charger gets confused.

Another thing to note is the change of AmpHour in a new battery you intentionally swap in. There are settings in forscan for choosing what size battery you use in the car. On my focus RS i swapped in an odyssey PC680, the original battery is not AGM but the PC680 is. I had to go in forscan to change it because charging voltage for AGM is higher but also more "delicate". Slight overvoltage can kill the AGM cells, however there is no setting in forscan for 10 to 12 AH for the PC680. I proceeded by choosing a 76 AH AGM setting. The result is the car never see the battery as ever meeting the requirement for start/stop to activate so it is kind of a side benefit for me.

 

[Neggytive]

The BMS is there to prolong your battery's life due to the start/stop system, it tells the alternator when to pump out the full voltage for charging and when to lower it for trickle accordingly when your battery is being depleted. Indirectly this also prolongs your alternator's life.

The catch is when swapping new battery into the car, the new battery should be charged externally of the car especially when you car has dual battery setup, installed in the car and then perform a BMS reset so the car knows the battery is fully charged.

Alternatively one can connect up a new battery and then charge the battery by connecting up the red terminal as normal but the negative terminal from the charger should not be connected to the negative or ground on the car, it goes directly on the BMS terminal which is usually found on the negative side. This does run a risk of frying stuff as i noted voltage spike and drop when i open the door or doing something in the car, the charger gets confused.

Another thing to note is the change of AmpHour in a new battery you intentionally swap in. There are settings in forscan for choosing what size battery you use in the car. On my focus RS i swapped in an odyssey PC680, the original battery is not AGM but the PC680 is. I had to go in forscan to change it because charging voltage for AGM is higher but also more "delicate". Slight overvoltage can kill the AGM cells, however there is no setting in forscan for 10 to 12 AH for the PC680. I proceeded by choosing a 76 AH AGM setting. The result is the car never see the battery as ever meeting the requirement for start/stop to activate so it is kind of a side benefit for me.

On some cars there is a battery reset procedure because like the oil life monitor, the car figures out age and such in the ECU ans as the battery ages it gives it more juice.

Put a new battery in and the additional charging will melt the plates, boil it, and just generally ruin it.

 

[Neggytive]

 

[Paul's stable]

@s197richie ..... I think you would be happier with your old s197.

I kept my 06 S197 when I bought my Dark Horse it was to much fun.

 

[s197richie]

I kept my 06 S197 when I bought my Dark Horse it was to much fun.

Wow you swapped in a Tremec six speed eh? That must have been a night and day improvement over the tr3650's remote body mounted shifter setup with all the rail flex.

 

[Paul's stable]

Wow you swapped in a Tremec six speed eh? That must have been a night and day improvement over the tr3650's remote body mounted shifter setup with all the rail flex.

It was an easy swap had a shop put it in. To old to be laying on my back lol. The Tremec Magnum XL is real nice and bullet proof.

 

[s197richie]

It was an easy swap had a shop put it in. To old to be laying on my back lol. The Tremec Magnum XL is real nice and bullet proof.

Even with a CHE chassis brace and torque limiters, speed shifting with my tr3650 is out of the question. 1st to 2nd under load have to give it a good minute and I've even gotten locked out of 3rd and ended up back in 1st. Surprised it wasn't a money shift tbh; rev limiter and a lifetime of Mobil 1 I guess.

 

[Paul's stable]

Even with a CHE chassis brace and torque limiters, speed shifting with my tr3650 is out of the question. 1st to 2nd under load have to give it a good minute and I've even gotten locked out of 3rd and ended up back in 1st. Surprised it wasn't a money shift tbh; rev limiter and a lifetime of Mobil 1 I guess.

I can bang shift a 7000 rpm all day long it was a big change.

 

[s197richie]

I can bang shift a 7000 rpm all day long it was a big change.

I bet; if I knew beforehand about the remote shifter I would have gone with a gently-preowned new edge or 4th gen F-body with a true toploader instead.

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