E torque or not

[Tncdrew]

That's not exactly true, the ess starts are handled by the etorque belt start generator but the entire chassis 12v system is always on when the vehicle is on and run off the 12v battery. I wouldn't call it a start battery, it is the only 12v battery. The ac, engine fans, seat heaters, radio, lights, etc are all run off that battery. It is charged by the 48v system via a DC to DC inverter.

This is how that system works. I would only add that the 12V battery does perform the initial start of a cold engine.

Sponsored

 

[hemiblas]

If it was the original 12V battery in a 2019, your friend's been on borrowed time.

I just replaced my main battery on my 2018, not because it went bad but because of what you said. I can't believe it lasted that long...

 

[Tncdrew]

I just replaced my main battery on my 2018, not because it went bad but because of what you said. I can't believe it lasted that long...

Its crazy when you consider the parasitic draw that these new vehicles impose on their batteries. I don't drive my JL regularly, so its often plugged into a trickle charger.

 

[hemiblas]

Its crazy when you consider the parasitic draw that these new vehicles impose on their batteries. I don't drive my JL regularly, so its often plugged into a trickle charger.

I did have the other battery go bad on my other 2018 about 6 months ago so I figured I was really on borrowed time. Agreed.

 

[longfiredragon]

Definitely etorque, if there's parts stores buy a new battery and swap it. Literally could be done with a crescent wrench in 10 minutes. If it's a problem with the charging system, that's beyond field repair anyway. Also the entire etorque is covered by an 8 year 80k mile emissions warranty, the 12v battery isn't. No risk, minimal effort, and likely all it needs. If it's more than that at least the new battery will probably get him to a dealer.

I will do further research because

That's not exactly true, the ess starts are handled by the etorque belt start generator but the entire chassis 12v system is always on when the vehicle is on and run off the 12v battery. I wouldn't call it a start battery, it is the only 12v battery. The ac, engine fans, seat heaters, radio, lights, etc are all run off that battery. It is charged by the 48v system via a DC to DC inverter.

This was not my understanding. Yes the 12V system is always on when the vehicle stops at a stop, ignition on etc. But the accessories are being run off the 48V battery, not the 12V. Otherwise what's the sense in a 48V battery.

Or you could look at it another way. If the 48V is charging the 12V, then it's still running the accessories off the 48V battery, just through the 12V system converted.

I will research it further.

 

[Zandcwhite]

I will do further research because


This was not my understanding. Yes the 12V system is always on when the vehicle stops at a stop, ignition on etc. But the accessories are being run off the 48V battery, not the 12V. Otherwise what's the sense in a 48V battery.

Or you could look at it another way. If the 48V is charging the 12V, then it's still running the accessories off the 48V battery, just through the 12V system converted.

I will research it further.

The accessories are 12V, the charging system is 48V so technically none of the accessories run off the 48v battery but the entire 12v system does. By extension you could argue that they run indirectly off the 48v system but I'm not sure if the DC to DC inverter is active when the engine is off during an ESS stop. It would make sense to me for it to shut down while the BSG is stopped as the 48v battery isn't being charged at that point but that I don't know.

 

[azjl#3]

Ok, I thought this was hashed out a year or so ago. 12v starter starts on all starts, 48v motor generator helps move vehicle first half wheel turn.

 

[longfiredragon]

The accessories are 12V, the charging system is 48V so technically none of the accessories run off the 48v battery but the entire 12v system does. By extension you could argue that they run indirectly off the 48v system but I'm not sure if the DC to DC inverter is active when the engine is off during an ESS stop. It would make sense to me for it to shut down while the BSG is stopped as the 48v battery isn't being charged at that point but that I don't know.

Yea, I get what your saying. I owned one of the first Ram e torques. My understanding was that when your in ess stop mode the 48V battery is keeping everything on the 12V side and all 12V accessories charged.

Then yes the belt driven e torque starts the engine.

However, going off memory because I did all the research but it was a 2020 ram, so 4ish years ago.

Would have do the research over at this point, and I no longer own an e torque, sooo. LOL.

 

[AnnDee4444]

I'm not sure if the DC to DC inverter is active when the engine is off during an ESS stop.

I'm pretty sure it's active. There is no voltage drop during ESS.

Ok, I thought this was hashed out a year or so ago. 12v starter starts on all starts, 48v motor generator helps move vehicle first half wheel turn.

Only cold-starts ignition-off starts.

The BSG also does other efficiency-related tricks like slowing the motor for a quicker upshift.

 

[longfiredragon]

Ok, I thought this was hashed out a year or so ago. 12v starter starts on all starts, 48v motor generator helps move vehicle first half wheel turn.

No, on e torque engines when in ess mode, ignition on but stopped engine not running. Take your foot off the brake and it is started by the belt driven e torque.

If the ignition is off, then the engine is started by the 12V battery.

But yes, it does also increase torque the first half of wheel rotation.

 

[Zandcwhite]

I'm pretty sure it's active. There is no voltage drop on ESS.

I honestly haven't paid much attention, but is there noticeable voltage drop on non-etorque ESS stops? The battery shouldn't discharge that fast and without etorque obviously the alternator is off when the engine is off.

 

[AnnDee4444]

I honestly haven't paid much attention, but is there noticeable voltage drop on non-etorque ESS stops? The battery shouldn't discharge that fast and without etorque obviously the alternator is off when the engine is off.

I haven't checked, but I assumed it's like every other 12V vehicle (12.6V when motor isn't running, ~14.2V with the alternator charging). I'm not even sure how there could possibly be more than 12.6V during not eTorque ESS events, since the alternator is responsible for anything above 12.6V.

eTorque is 14-ish volts during ESS (usually a few tenths lower when hot).

 

[Boatbuilder88]

The main AGM battery in my 2019 2.0L eTorque-equipped Jeep died without warning one morning. (The Jeep was 5 years old.) Glad I was home at the time. The dash lit up like a Christmas tree and the Jeep wouldn't start. My old lead acid batteries used to feel weak during startup when it was time for replacement. I guess these AGM batteries are quite different.

 

[AnnDee4444]

The 48V battery covers for a weak 12V battery for a long time (months in my case). ESS will stop working with a perpetual "not ready" state shown if you scroll to the correct menu in the gauge cluster.

 

[azjl#3]

OK my bad, but last year or so, a thread said the ESS on an etorque used starter motor no matter what, ....

Sponsored