3.6L ESS Aux Battery Bypass

LooselyHeldPlans

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I admittedly didn’t read all 34 pages of this thread, but am I wondering about the thread specs of the wing nuts used to attach the bypass.

@Jebiruph, do you happen to know these specs? Might be a useful update to the original post.
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Apologies if this has been explained earlier in the thread ( I may have just missed it).

when viewing the voltage on the instrument cluster or through the 4x4 page, I assume when driving this is the alternator output and wondered when the rare occasions that the stop/start system actually operates and stops the engine, does this voltage display then show that of the main or auxiliary battery? I was thinking the latter but noticed that after the engine starts again, the voltage slowly increases back to 14v or whatever, making me then think that it perhaps only shows the voltage of the main battery, regardless.

Thanks in advance...
 
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Jebiruph

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Apologies if this has been explained earlier in the thread ( I may have just missed it).

when viewing the voltage on the instrument cluster or through the 4x4 page, I assume when driving this is the alternator output and wondered when the rare occasions that the stop/start system actually operates and stops the engine, does this voltage display then show that of the main or auxiliary battery? I was thinking the latter but noticed that after the engine starts again, the voltage slowly increases back to 14v or whatever, making me then think that it perhaps only shows the voltage of the main battery, regardless.

Thanks in advance...
I'm not sure which battery voltage is displayed during an auto stop. When I watched mine, there seemed to be a delay after the restart before the alternator voltage was displayed. That would indicate to me that it was monitoring the aux battery with the delay being from the battery relay reconnecting the aux battery.
 

fourseasons1621

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So can’t we follow this method of using the jumper terminals between N1 & N2 and wire a solenoid between the disconnected aux battery and ground, then use an aux switch inside the cab to toggle an auto jump start on and off plus reconnect charging to the aux battery whenever you feel necessary?
 
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Jebiruph

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So I had the Jeep not start on me a few days ago.. had the wife jump me and went along my way. Stumbled across this thread. I have a 2018 jl that hasn’t received the TSB as far as I know.

so my problem is when I disconnect aux ground to main battery and apply the jumper. The Jeep doesn’t start. Just hear clicking. If I reconnect the ground the Jeep starts fine. What am I doing wrong? I’ve attached pictures of someone could help.

the ground for the aux is on the same post as my winch and aux switch ground. I’ve added a red arrow to show the aux ground which I removed and taped with electrical tape.

5935FE16-F304-499D-989E-B3CDE0C6434A.jpeg


0BE653C3-E8FA-41AF-B0D0-91476E37F0A0.jpeg
 
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Jebiruph

Jebiruph

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So I had the Jeep not start on me a few days ago.. had the wife jump me and went along my way. Stumbled across this thread. I have a 2018 jl that hasn’t received the TSB as far as I know.

so my problem is when I disconnect aux ground to main battery and apply the jumper. The Jeep doesn’t start. Just hear clicking. If I reconnect the ground the Jeep starts fine. What am I doing wrong? I’ve attached pictures of someone could help.

the ground for the aux is on the same post as my winch and aux switch ground. I’ve added a red arrow to show the aux ground which I removed and taped with electrical tape.

5935FE16-F304-499D-989E-B3CDE0C6434A.jpeg


0BE653C3-E8FA-41AF-B0D0-91476E37F0A0.jpeg
It looks to me like your aux battery is the good battery and the main battery is the bad battery. Try leaving the aux connected and the main disconnected and see what happens.

You should probably get both batteries charged and load tested.
 
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