Where's my battery?

[Outrider1]

So I go and get a main battery and the auxiliary to change out on my 2021 Willys. This is the 3.6 engine. No towing package or other options from the standard Willys.
Disconnect/remove the main and take off the fuse box down to get at the auxiliary. Only there is NO auxiliary battery! No positive or negative connections, nothing!
So my ESS runs off the main only.
Has anyone else run into this situation?

Sponsored

 

[Kracka]

You likely have the 48V eTorque system (which is a good thing). I am very happy with it in our 2023 and love how seamless the ESS system is.

When you replace your main 12V battery, install a quality 94R and you'll be set for 5+ years (ACDelco AGM is my personal choice).

 

[Terrymo]

Etorque system is still built with an empty battery box for a secondary battery in the fender well. Rather than counting battery cables and coolant tanks, simply take a minute and look under your Jeep. If you see this you have an etorque. If not you don’t.

 

[BigRedRidinHood]

Also look at your Monroney Sticker. It will specify eTorque if you have it. I am not aware that any 2021 Wrangler was made without either one of these features but I'm sure that there are people far more knowledgeable than me on this site that will confirm or deny this assertion. I think eTorque is a great technology that has proved pretty bulletproof so far.

 

[hamiamham69]

If you bought the Jeep pre-owned the. Maybe the previous owner took the aux battery out for you … thereby doing you a favor

 

[Outrider1]

If you bought the Jeep pre-owned the. Maybe the previous owner took the aux battery out for you … thereby doing you a favor

Ordered it new.

 

[Terrymo]

Ordered it new.

Did you get a chance to look under the Jeep using the pics posted to see if there is an etorque battery?

 

[Wbino]

How to Identify If Your Jeep Wrangler Has eTorque
If you're unsure whether your JL Wrangler has an eTorque system, here’s how you can find out:

1. Check Under the Hood

• Instead of a traditional alternator, an eTorque-equipped Jeep has a belt-driven motor-generator unit (MGU).
• On the 3.6L V6, the MGU is mounted near the front of the engine.
• On the 2.0L Turbo I4, it is similarly positioned but more compact.
• Look for extra wiring and a small cooling system tied to the 48-volt battery—these are indicators of eTorque.

2. Locate the 48-Volt Battery Pack

• The eTorque system's battery is mounted under the rear seat (driver side) and positioned opposite the fuel tank.
• If you do not see a secondary battery in this location, your Jeep likely does not have eTorque.

3. Check the Window Sticker or Build Sheet

• If you still have the original window sticker, look under engine options for "eTorque Mild Hybrid System".
• If your Wrangler is used, request the build sheet from Jeep’s website or a dealership.

4. Observe the Start-Stop System Behavior

• Start your Jeep and bring it to a stop.
• eTorque models have a much smoother and quicker stop-start system compared to older systems. The engine restarts almost instantly, without the typical lag of traditional start-stop setups.

5. Run a VIN Check

• Enter your VIN on Jeep’s online build sheet portal or ask a dealership to confirm if your Wrangler has eTorque.

6. Take It for a Test Drive

• If you notice a subtle but noticeable torque boost when accelerating from a stop, especially in stop-and-go traffic or off-road crawling, your Wrangler likely has eTorque.

 

[kah.mun.rah]

So I go and get a main battery and the auxiliary to change out on my 2021 Willys. This is the 3.6 engine. No towing package or other options from the standard Willys. Not an e Torque.
Disconnect/remove the main and take off the fuse box down to get at the auxiliary. Only there is NO auxiliary battery! No positive or negative connections, nothing!
So my ESS runs off the main only.
Has anyone else run into this situation?

For anyone reading this that does have an aux battery, NEVER access it by pulling apart your fuse tray. It is much easier and safer to access through the front passenger wheel well.

 

[Outrider1]

Etorque system is still built with an empty battery box for a secondary battery in the fender well. Rather than counting battery cables and coolant tanks, simply take a minute and look under your Jeep. If you see this you have an etorque. If not you don’t.

You are correct. I do have the e Torque!

Sponsored