Jeep won’t start after towing

[Nick68]

I’ve got a 2008 country coach magna class A, I’m towing a 2020 jeep Wrangler, only been on 3 trips , every time I get to destination my jeep won’t start , dash lights up but car won’t start , anyone one having the same issue?

 

[Scotttkd2]

Most power hungry newer towed vehicles are going to need a 12volt charge line to keep the batteries up while being towed. Do you know if your harness in the Jeep is doing that??

 

[widdershins]

Also, if you are towing with the ignition on... that would make it worse. I don't know for sure if 2020 user manual is wrong, but I do know that the user manual for a 2013 says you need to leave the ignition on.. which is 100% wrong for that model.

 

[John&Andrea]

Towed Battery Charger Plus for flat towing

RVi Towed Battery Charger Plus, charge line replacement for flat towing a vehicle. Great peace of mind for the towed battery while towing a car behind a motorhome. Often used with RVibrake. TBC+

rvibrake.com

I just ordered this, I have not installed yet.

 

[sheridany]

That’s what I have in my jeep. Works great.

 

[Nick68]

Most power hungry newer towed vehicles are going to need a 12volt charge line to keep the batteries up while being towed. Do you know if your harness in the Jeep is doing that??

It’s not doing it, I think might have install a battery charger

Most power hungry newer towed vehicles are going to need a 12volt charge line to keep the batteries up while being towed. Do you know if your harness in the Jeep is doing that??

 

[Wayne Daul]

Need charge line to both batteries, if you have push to start. Make sure you have power from motor home.

 

[Av8r]

I have a 2020 Jeep Gladiator (basically your Wrangler, with a truck bed) that I pull behind a 2021 Newmar Superstar, using a Ready Brute Elite II towbar. It's all wired with a CoolTech harness, which involves splicing into the Jeep's existing wiring. It completely (physical air gap)isolates the Jeep's electrical system when towing, forcing power to come from the coach, and thus insures no drain on the Jeep battery while towing.

First time I towed, I arrived with a dead battery. I'm talking dead to the point that Jeep replaced both the main and the aux batteries under warranty.

Ultimately, I have developed a theory which may or may not be of value for the OP:

The Jeep has a start button, not a keyhole slot. During the hookup process, there is a point where you turn off the running motor. You push the button, and the motor stops. Just like it's supposed to do.

But, because the button is located behind the steering wheel in your line of sight, you fail to notice that the ignition did not go to "OFF", but rather it went only to the "ACC" position. You continue through your hookup checklist, and away you go, with the ignition in "ACC" instead of "OFF". Your Jeep battery is thus powering who knows what until you arrive at your destination with a dead battery!

I haven't had a repeat occurrence since I began paying strict attention to the ignition switch reading "OFF", like it's supposed to.

Hopefully this simple fix is your issue, and prevents you from having to install more gizmostats into your system!
__________________

 

[Gizmo]

I used the Roadmaster towing harness and also have a 2022 Jeep Wrangler Rubicon I agree with the above about the ACC/OFF button and found myself incorrectly leaving the switch in ACC. I also have a drop-in braking system that sits on the driver's floor I have found if I tow for two days in a row I probably will have a dead battery and if I start the Jeep each day of towing and let the battery recharge I don't have any problems. I do not have a charge line but looking at installing the Roadmaster version as I did on my 2017 Jeep Wrangler which solve the problem.

https://www.amazon.com/dp/B01EXKV54W/?tag=rvf01-20

 

[Nick68]

I have a 2020 Jeep Gladiator (basically your Wrangler, with a truck bed) that I pull behind a 2021 Newmar Superstar, using a Ready Brute Elite II towbar. It's all wired with a CoolTech harness, which involves splicing into the Jeep's existing wiring. It completely (physical air gap)isolates the Jeep's electrical system when towing, forcing power to come from the coach, and thus insures no drain on the Jeep battery while towing.

First time I towed, I arrived with a dead battery. I'm talking dead to the point that Jeep replaced both the main and the aux batteries under warranty.

Ultimately, I have developed a theory which may or may not be of value for the OP:

The Jeep has a start button, not a keyhole slot. During the hookup process, there is a point where you turn off the running motor. You push the button, and the motor stops. Just like it's supposed to do.

But, because the button is located behind the steering wheel in your line of sight, you fail to notice that the ignition did not go to "OFF", but rather it went only to the "ACC" position. You continue through your hookup checklist, and away you go, with the ignition in "ACC" instead of "OFF". Your Jeep battery is thus powering who knows what until you arrive at your destination with a dead battery!

I haven't had a repeat occurrence since I began paying strict attention to the ignition switch reading "OFF", like it's supposed to.

Hopefully this simple fix is your issue, and prevents you from having to install more gizmostats into your system!
__________________

Thanks!!! I'll pay more attention next time, maybe that's what I'm doing wrong.