Tazer ESS Battery Testing

[WranglerMan]

Quick update on day #3

The Mrs came home early so decided we would head towards downtown to our favorite Deli to get a sandwich and those who know Houston know that’s not a quick trip so as I reported in my previous post my morning voltage was well within being 100% charged and after running my morning errands the EVIC voltage dropped to the 12.7-13 range, well as we were heading DT we had several ESS start/stops and at one point the EVIC displayed voltage was close to 14 rolling down the road and ESS worked perfectly at all stops.

After having our late lunch early dinner we headed back and as we were cruising down the highway the displayed EVIC voltage just dropped from the 13.3 to 12.7 by the time we got close to home but never dropped lower than 12.7-12.8 so I’m guessing the voltage is supposed to swing as Joe from Zauto described and I’m sure the more ESS stops one has along with what you have running dictates how high it will spike to after it restarts.

Anyway I came home and checked the main battery and it was right at 12.75 and I can’t ask for more than that for a charged battery

I think tomorrow I will follow @Jebiruph advce on isolating the ESS battery and checking the voltages separately as so far I have been looking at combined voltages

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[WranglerMan]

Day 4

12.60
12.59
12.59
13.2

Today very unenventful, did not go anywhere just went out and checked resting voltages and cranked the Jeep up and got the EVIC voltsge, took a quick drive to the mail box and back and not long enough to even warm the engine so ESS was clear to engage

At day 6 or 7 going separate batteries and check voltages separately but so far no crazy things going on and voltages swing like they are supposed to depending on the level of charge.

 

[WranglerMan]

First off hope everyone had a great Christmas, now for today’s voltwfes and I added one more voltsge and the is the last one listed and it’s the ESS battery separated from the main and not a combined voltage

The ESS voltage seems low but still it’s around 80% charged, not sure why its not 100% like the main but maybe due to its size it dissipates voltage more quickly at rest

Anyway here are the voltages today, had some short errands to run and ESS worked as designed, I’m more then likely going to run 3-4 more days like this then plug in the Tazer after to another trickle charge so I can keep things starting the same way for comparison

Day 5

12.56 Main
12.56 N1
12.56 N2
13.9 EVIC
12.48 ESS

 

[WranglerMan]

Well just one more day then I’m going t put the JL on a tender and plug the taser in and disable ESS and run the same amount of time with it that I have been doing and checking voltages everyday.

For the past week I have had zero issues and ESS has worked just like it’s supposed to and my voltages seem to be pretty steady

So here are today’s numbers

Day 6

12.66 Main
12.66 N1
12.66 N2
13.3 EVIC
12.64 ESS

 

[OldGuyNewJeep]

I agree. ESS sucks.

So, even though I’ve had zero issues, I just checked my battery with a multimeter. 12.44. That’s only about 50% charged. No good.

<sigh>

Unplugged my Tazer, but left it married. I’ll charge my battery with a tender and monitor. If it never dips under 12.6 I’ll be on board with you that Tazer has a bug. Hopefully @joe@zauto is on the case.

Anyway, we’re lucky that all we’ve got to complain about at Christmas is a minor annoyance with a toy, and so I’ll take this discovery with a grain of salt.

OK, so my Tazer has been unplugged since I posted this ^

Guess what? My battery voltage dips overnight, anyway. This morning it was 12.39 volts. Jeep starts and ESS works.

I’m confused. @Rhinebeck01, what can you tell us about “normal” battery voltages? I know you’re not an FCA engineer, but I value your opinion on this topic. With my boat and other vehicles I’ve always gone by “anything less than 12.6 is not good.” Is the JL different because my multimeter is reading two batteries wired in parallel? When I put a tender on it overnight, or even just drive it for a bit, it’ll read 12.6x. Let it sit overnight (garage is about 50 degrees) and it’s back down to 12.4ish.

Basically, since my battery is reading the same as when my Tazer was plugged in, I want to know if I’m unaffected by the issue @joe@zauto is trying to debug. I’d love to plug it back in. I miss it!

Edit - I’m testing voltage with a multimeter at the terminals.

 

[WranglerMan]

@OldGuyNewJeep you need to check batteries separately, I initially checked the main battery at the posts then at N1 and N2 to give me a combined average then the past couple days I have pulled the negative ESS cable so I could check it separately and over the course of almost a week my voltages have been the following

12.62 main
12.61 ESS
13.2 EVIC

I still have one more day to go but as you can see with no Tazer plugged in my voltages are very consistent and the averages are very close to a fully charged battery of 12.66 @ 70 deg, I am not exposed to the temps you are seeing so can’t comment how much they would drop.

 

[OldGuyNewJeep]

@OldGuyNewJeep you need to check batteries separately, I initially checked the main battery at the posts then at N1 and N2 to give me a combined average then the past couple days I have pulled the negative ESS cable so I could check it separately and over the course of almost a week my voltages have been the following

12.62 main
12.61 ESS
13.2 EVIC

I still have one more day to go but as you can see with no Tazer plugged in my voltages are very consistent and the averages are very close to a fully charged battery of 12.66 @ 70 deg, I am not exposed to the temps you are seeing so can’t comment how much they would drop.

Can you elaborate on your process for checking individual voltages? Looking at this diagram, I see a couple of different ways it might be done: https://www.jlwranglerforums.com/forum/threads/3-6l-ess-battery-diagram.14401/

 

[WranglerMan]

Can you elaborate on your process for checking individual voltages? Looking at this diagram, I see a couple of different ways it might be done: https://www.jlwranglerforums.com/forum/threads/3-6l-ess-battery-diagram.14401/

When I check voltages I do the following, I believe I have covered all points after looking at @Jebiruph ESS bypass thread, I use a digital Klein 400 mm and checked the main right at the main +/- then I put the negative on N2 ( another point for main) leaving the positive lead on the main for both, then while keeping the positive lead on the main I put the negative on N1 ( combined voltage of main and ESS ) then I pull the negative ESS lead off the nagative terminal and check just ESS voltsge only

I’m sure this is overkill on checking voltages as if you look at post #87 below you will see that you really only need to separate the ESS negative from the main negative but I figured I would also check N1 and N2 just to cover all points maybe@Jebiruph can chime in and confirm what I’m telling you is correct

https://www.jlwranglerforums.com/forum/threads/3-6l-ess-battery-diagram.14401/page-6

 

[Jebiruph]

When I check voltages I do the following, I believe I have covered all points after looking at @Jebiruph ESS bypass thread, I use a digital Klein 400 mm and checked the main right at the main +/- then I put the negative on N2 ( another point for main) leaving the positive lead on the main for both, then while keeping the positive lead on the main I put the negative on N1 ( combined voltage of main and ESS ) then I pull the negative ESS lead off the nagative terminal and check just ESS voltsge only

I’m sure this is overkill on checking voltages as if you look at post #87 below you will see that you really only need to separate the ESS negative from the main negative but I figured I would also check N1 and N2 just to cover all points maybe@Jebiruph can chime in and confirm what I’m telling you is correct

https://www.jlwranglerforums.com/forum/threads/3-6l-ess-battery-diagram.14401/page-6

Chiming in. With all cables in place and the PCR connecting the batteries, N1, N2 (all N terminals) and the Main battery should be electrically the same, the combined battery voltage. A significant difference between N1 and N2 would indicate a bad PCR or blown high capacity fuse. I would measure both batteries after they are isolated from each other with the ESS negative cable disconnected from the Main battery terminal. It looks like you aren't getting a measurement from the Main battery by itself.

 

[OldGuyNewJeep]

Chiming in. With all cables in place and the PCR connecting the batteries, N1, N2 (all N terminals) and the Main battery should be electrically the same, the combined battery voltage. A significant difference between N1 and N2 would indicate a bad PCR or blown high capacity fuse. I would measure both batteries after they are isolated from each other with the ESS negative cable disconnected from the Main battery terminal. It looks like you aren't getting a measurement from the Main battery by itself.

This would make a great YouTube tutorial.

 

[WranglerMan]

@Jebiruph if I pull the negative ESS cable off the main and then put the +/- meter leads on the main battery posts this should give me the mains voltage correct ?

 

[Jebiruph]

@Jebiruph if I pull the negative ESS cable off the main and then put the +/- meter leads on the main battery posts this should give me the mains voltage correct ?

Yes.

 

[WranglerMan]

Yes.

And then if I leave the positive lead on the main and put the negative lead on the ESS cable I removed I should then only get the ESS battery voltsge correct

 

[Jebiruph]

And then if I leave the positive lead on the main and put the negative lead on the ESS cable I removed I should then only get the ESS battery voltsge correct

Yes. Both battery's positive cables connect to the main battery positive, so moving the negative meter lead to the disconnected ESS negative cable gives you ESS battery voltage.

 

[WranglerMan]

@Jebiruph it seems to over complicate things taking voltages off N1and N2, as you have pointed out to get just basic voltsge of each both battery one only needs to remove one cable and just swap the nagative leads around

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