3.6L ESS Aux Battery Bypass

[Jebiruph]

A while back one of the you tubers I watch, Kevin and Britney with Lite Brite, showed a way to jump the jeep using a jumper wire. Was this related to possibly a bad aux and then using the bypass that has been stated in this thread? Or did he do something else to “jump” the jeep? Just trying to make sure I understand. I plan to build a jumper wire as well per the instructions in this thread as I don’t want to be stranded while camping or off roading.

I did a search and can’t for the life of me find the episode where Kevin does this, maybe someone on here has a link to it but either way. Would like to know what he did so I don’t end up stranded.

I saw that, they were demonstrating that if the aux battery fails, but the main battery is good, the jumper gets you past the cold start aux battery test. They later replaced the temporary jumper with a permanent unfused jumper, I would only recommend a fused jumper unless the aux battery is removed.

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[MadDog27]

I saw that, they were demonstrating that if the aux battery fails, but the main battery is good, the jumper gets you past the cold start aux battery test. They later replaced the temporary jumper with a permanent unfused jumper, I would only recommend a fused jumper unless the aux battery is removed.

Perfect! Thank you for the help and all the work you’ve put into this thread.

 

[cbrenthus]

I see. So the point of eliminating the AUX Battery is what then ?
Because it is harder to jump if it dies or cause it is acting parasitic on the MAIN Battery ?

I've read a lot of Aux battery failures, and when it goes it takes the main with it. I don't want to have to worry about 2 batteries in parallel, especially when I don't use ESS.

 

[c2m2h3]

I TOTALLY Agree....

So the Jumper BYPASSES the Aux ? and uses the Main for the Cold Start Aux Test and everything else ? Basically taking the 2 Batteries OUT of Parrell ?

Chris

 

[Jebiruph]

I TOTALLY Agree....

So the Jumper BYPASSES the Aux ? and uses the Main for the Cold Start Aux Test and everything else ? Basically taking the 2 Batteries OUT of Parrell ?

Chris

The ESS system has main battery circuits and aux battery circuits that are connected by the PCR (Power Control Relay) except when auto stopped and during a brief cold start test. All the jumper does is keep the main battery circuits and aux battery circuits connected, regardless of what the PCR is doing. Virtually the same thing is accomplished by unplugging the PCR, since it can't separate the circuits when it is unplugged. This allows you to run on either or both batteries. All system modifications are at your own risk.

 

[c2m2h3]

I thought that the goal was to prevent the Aux from Draining the Main.....This sounds like they are specifically tied together with the Jumper.....How does the Jumper help that situation ?

 

[Jebiruph]

I thought that the goal was to prevent the Aux from Draining the Main.....This sounds like they are specifically tied together with the Jumper.....How does the Jumper help that situation ?

Since you can run on either or both batteries, you can disconnect either battery you want at your own risk.

 

[c2m2h3]

So connect both with the Jumper, and then you can disconnect the AUX (Negative lead ?) and it doesn't cause a drain to the Main Battery ? (At your own risk, of course)

 

[Jebiruph]

So connect both with the Jumper, and then you can disconnect the AUX (Negative lead ?) and it doesn't cause a drain to the Main Battery ? (At your own risk, of course)

That's correct, a disconnected aux battery will not drain the main battery and the negative lead seems to be the obvious way to disconnect it.

 

[c2m2h3]

Thanks again, again, again and I'm sure several more times, Jerry

Makes sense....

 

[Rufus]

That's correct, a disconnected aux battery will not drain the main battery and the negative lead seems to be the obvious way to disconnect it.

But just to accomplish the bypass you only need the jumper, correct? I just want to have it for the situation when the aux battery dies.

 

[jeepdabest]

But just to accomplish the bypass you only need the jumper, correct?

Sort of. I purchased the jumper. Now, I'm saving up for the Jeep.

 

[c2m2h3]

I believe that the Jumper is also necessary if you should need to jump the vehicle with something like a jump pack.....There has been info posted about how to connect the Jumper, and what to disconnect from the batteries when jumping the JL. I can't fully explain it, but I know I have the info saved somewhere....

 

[Rufus]

I believe that the Jumper is also necessary if you should need to jump the vehicle with something like a jump pack.....There has been info posted about how to connect the Jumper, and what to disconnect from the batteries when jumping the JL. I can't fully explain it, but I know I have the info saved somewhere....

I will go back through this thread but my understanding was that the jumper would solve the problem of the main battery being able to trigger the relay to allow it to crank the starter (as opposed to the aux battery having to trigger the relay).

 

[c2m2h3]

I'll let the pros answer that....it "sounds correct"......

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