Jeep wants you to pay for a flat tow harness to fix the wobble

[rpasetto]

@Garyp47: I also thought about using one switch to control both circuits but didn't want to "modify" FCA/Jeep's system in a way that would allow them to point a finger at the change if something went wrong. Others have made such mods, including automating the process using relays energized when the power cable from the coach is connected. Using a separate switch to control the fused circuit is easy to 'undo' should it be necessary to bring the system back to the original.

I should mention also...
1. We always flip the console switch (which isolates the EPS circuitry from the rest of the vehicle) and then energize the EPS. We've heard about issues related to the opposite sequence.
2. There appears to be a time delay (maybe 30 sec.) between activating the EPS circuit and the power steering energizing.
3. Whatever choice you make, a charge line from MH to Cherokee is recommended to reduce chances of battery discharge.

[dpinvidic]

There are two parts to this wobble fix.
1. Provide power to the EPS
2. disconnect the EPS module from the CAN bus

The fuse and relay (wrapped in the tow cable harness), isolats the EPS power from the rest of the jeep and then gives 12v to the EPS motor.

The switch in the console is a DPDT, and it isolates the EPS module from the CAN bus.
It would have been a lot more wire routing to combine into one switch so FCMA took the cheap route AKA Micky Mouse

Dan

[Garyp47]

Thanks for all the help. This is getting quite complicated compared to my Tracker which takes 4 steps to tow:

1. Ignition key to accessory position to unlock steering wheel.
2. Transfer case in neutral.
3. Trans in Park.
4. EM brake off.

I am developing a custom checklist for the Jeep procedure. If anyone is interested in reviewing it for me, I will send it to you. At 2 months away from 70, it's a bit more difficult to remember all this stuff. Especially when you don't do it a lot.

[dtoste77]

Originally Posted by Garyp47

Thanks for all the help. This is getting quite complicated compared to my Tracker which takes 4 steps to tow:

1. Ignition key to accessory position to unlock steering wheel.
2. Transfer case in neutral.
3. Trans in Park.
4. EM brake off.

I am developing a custom checklist for the Jeep procedure. If anyone is interested in reviewing it for me, I will send it to you. At 2 months away from 70, it's a bit more difficult to remember all this stuff. Especially when you don't do it a lot.

The harness comes with a check lists. Here's a pic. They should give it to you after the install.

[Vaark]

Originally Posted by Mr_D

Towing four down is beyond what Jeep designed the stock vehicle to do. So they would have a right to charge for the modifications needed, just like they do for the wiring, brake system and tow brackets.

This isn't true. My 2016 Cherokee was advertised as flat towable and it even had instructions in the manual on how to do it.

I had a time getting my dealer to install the harness. Service manager said he wouldn't do it unless FCA told him to. I called FCA and they said, of course, they would do it free and would notify the service manager. Service manager claimed to never have received the authorization. After a while, he said ok, he would do it just for me and would order the parts. And he never called me back again to say the parts had arrived. Back and forth it went until I finally asked if the parts had arrived and they said they had it in stock all the time. I scheduled to have it done and they did it free.

What an aggravation!

[rlcarson2]

Originally Posted by jimfh2o

I had the AB kit installed at a dealership in Denver about a month ago...they did a great job. After about 30 minutes on the phone with Jeep Customer Service and Jeep Wave, they covered the bill...about $375. A few days later I installed the RVi BRAKE Towed Battery Charger...very easy install...parts were about $55. So now I flip a red switch inside the Jeep and open the hood to insert a 10 amp fuse...adds about 2 minutes to the process...not a big deal to me. All in all, we love the Cherokee Trailhawk and now have an assurance we may never suffer the "death wobble".

When the Mopar Flat Tow Wiring Kit is installed, does it include tail light wiring? If it is, great. If not, how do you connect both the mopar kit and the separate tail light kit to the RV? Is there an adapter to allow to connectors to be attached to the RV?

[BobGed]

Originally Posted by rlcarson2

When the Mopar Flat Tow Wiring Kit is installed, does it include tail light wiring? If it is, great. If not, how do you connect both the mopar kit and the separate tail light kit to the RV? Is there an adapter to allow to connectors to be attached to the RV?

The Mopar tow wiring kit when installed by a dealer is a stand alone fix that is contained entirely within the Cherokee. It has no connection whatsoever to the coach. Once it is installed it is a good idea to install a charge line from the coach to the Cherokee, particularly if you're going to be towing for multiple days without starting the Cherokee.

There is an after market modification posted earlier in this thread by dpinvidic that automatically activates the tow mode when connected to the coach.

The light kit, whether from Jeep or a third party, is a totally separate connection between the coach and the Cherokee.

[Garyp47]

I am researching running 12V into my towed Cherokee to help maintain the battery charge when traveling and I have verified I have a 12V source at my 7-pin trailer connection at the rear of the RV. 12V is present on the pin (identified as +12V on a few of the Winnebago wiring harness diagrams I found online) only when the RV is running.

If I do decide to go ahead with this, I would like to at least know there this circuit is protected/fused from. I cannot find any documentation on my motorhome and/or Ford chassis manual that tells me exactly which protective device it is and where it's at. I have found a 30A fuse designated for a trailer tow electric brake controller in the Ford manual. But nothing for the 12V source. The 7 pin connector does have a separate pin for each of these two designations.

I was able to verify 12V was present with the engine running at the connector pin marked 12V and no voltage present on the pin designated for a trailer tow electric brake controller. I was alone so I couldn't step on the brakes and measure it.

I am thinking this 30A fuse feeds both these pins. I should have pulled the fuse and tested it with the engine running but didn't think of it until after I was home.

Anyone with a Ford F53 chassis have any experience with this? I tried Winnebago support, Ford truck support and Ford RV support. I can't believe they can't tell me but I am waiting for a call back from the Ford RV support.

[stoyles]

Hi Folks,

I have a 2016 Cherokee Trailhawk and tow 4 flat behind my RV. I have the Mopar Flat Tow kit installed, wiring from the RV to my lights, the battery trickle charger installed and the line to my brake buddy all installed. It literally adds 1 minute to the final tow setup sequence to flip the switch, pop the hood and insert the fuse. Have towed 1000's of miles without issue. While there may be more elegant solutions I feel this is a great setup overall and unseen to the overall look and functionality of the Cherokee. I had a 2013 Fit previous and it took no time to hook up and didn't even need a brake buddy due to its weight. However Honda's lack of backing their products transmission failures led me to Jeep. A few minutes is well worth it compared to some of these advertised flat towable vehicles where you are really gambling on if the transmission will hold up.

Jason

[Vaark]

Has anyone seen a schematic of the Flat Tow Harness?

[BobGed]

Originally Posted by BillJump

Has anyone seen a schematic of the Flat Tow Harness?

I have a copy of the complete installation instructions issued by FCA, but the file is too large to post here. If you PM me with your email address I'll send you a copy.

[dpinvidic]

Originally Posted by BillJump

Has anyone seen a schematic of the Flat Tow Harness?

What are you trying to find out?
See my post Make jeep flat tow automatic

It has the full schematics, including replacement of the console switch with a relay.
The harness does two things.
1. isolates the EPS controller from the CAN bus.
2. Isolates the EPS power lead, and connects it to 12v to power the EPS only

Dan

[Garyp47]

Originally Posted by stoyles

Hi Folks,

I have a 2016 Cherokee Trailhawk and tow 4 flat behind my RV. I have the Mopar Flat Tow kit installed, wiring from the RV to my lights, the battery trickle charger installed and the line to my brake buddy all installed. It literally adds 1 minute to the final tow setup sequence to flip the switch, pop the hood and insert the fuse. Have towed 1000's of miles without issue. While there may be more elegant solutions I feel this is a great setup overall and unseen to the overall look and functionality of the Cherokee. I had a 2013 Fit previous and it took no time to hook up and didn't even need a brake buddy due to its weight. However Honda's lack of backing their products transmission failures led me to Jeep. A few minutes is well worth it compared to some of these advertised flat towable vehicles where you are really gambling on if the transmission will hold up.

Jason

Jason,

what trickle charger are you using?

I am STILL waiting for the Jeep dealer here to get all the parts. Very frustrating. Apparently he has the Mopar wiring kit but not the Blue Ox baseplate mounts. Backordered for two weeks???? I am beginning to think I made a huge mistake buying this vehicle.

[DrDaveMA]

You do not need a trickle charger, use pin 4 in your 7 pin connector and tie it to the battery in the toad. Be sure to put a fuse/circuit breaker at the battery of each end in case something should short.

Here is a link to the pin out for a 4, 6 and 7 pin connector.

http://www.dieselhub.com/towing/trailer-wiring.html