Jeep GRAND Cherokee death wobble!

[the sights]

Originally Posted by ftodaro

Ok i just wanted to report that I have a 2018 GC, i had the harness installed and i towed about 500 miles following the instructions on activating the EPS and the steering wheel was firm not active. I did not test it just assumed it was active. So today i again activated the EPS with the harness following instruction, and it was firm.

Clearly the instructions are wrong when they tell you to flip the switch and fuse with the motor off.

I followed the process while the motor was running and the EPS remained active.

Thank you for the poster above who pointed this out days ago, i just not have the time to test my instructions and install.

I did tow that first 500 miles without issue but its nice to know how to activate it correctly.

Carry on.

Thanks for the update, With the car off and EPS active (steering wheel loose) can you also have the transfer case in neutral? some have reported that wheel is loose till placing the transfer case in neutral then it firms up.
Thanks

[ftodaro]

Originally Posted by the sights

Thanks for the update, With the car off and EPS active (steering wheel loose) can you also have the transfer case in neutral? some have reported that wheel is loose till placing the transfer case in neutral then it firms up.
Thanks

What i did today is to first put the transfer case in Neutral and tried activating the EPS the way the instructions say with engine off no good. so I just started the engine with it still in Neutral turned on the EPS shut motor off EPS was active and still in Neutral so the only change is the program is to do the EPS before you shut the motor off.

[deblas]

Originally Posted by ftodaro

What i did today is to first put the transfer case in Neutral and tried activating the EPS the way the instructions say with engine off no good. so I just started the engine with it still in Neutral turned on the EPS shut motor off EPS was active and still in Neutral so the only change is the program is to do the EPS before you shut the motor off.

Frank, I have had no luck keeping the EPS energized after placing the transfer case into neutral. I can get the EPS to remain energized using the steps provided by KYerves in post #416 but not when transfer case is in neutral. I will confirm again tonight, if your steps (transfer case then EPS harness) do keep the EPS energized.

Something I do not get is the "Service Power System" indication as noted by KYerves on #416.
Nor do I get any other indication....Do you get this service light or anything when you flip the switch with the GC running?

[ftodaro]

Originally Posted by deblas

Frank, I have had no luck keeping the EPS energized after placing the transfer case into neutral. I can get the EPS to remain energized using the steps provided by KYerves in post #416 but not when transfer case is in neutral. I will confirm again tonight, if your steps (transfer case then EPS harness) do keep the EPS energized.

Something I do not get is the "Service Power System" indication as noted by KYerves on #416.
Nor do I get any other indication....Do you get this service light or anything when you flip the switch with the GC running?

I do not know if this makes a difference but i went through the normal procedure of putting the GC into Neutral, let it go to sleep like you are instructed to do, then I started it and flipped the switch for the EPS and plugged in the fuse (flipped the switch) i installed. and it was powered.

[ftodaro]

I hate to over think this but its a bad habit, so my instructions For the EPS harness says that its to "dampen" the steering rack. I would think that when there is no power to the unit it would be "dampened" I assume the wobble comes from the stiff non powered rack not being able to respond or correct quick enough and that is why it wobbles, Its not a problem when going straight, it can correct and keep up, but on those sharp turns it cannot react quick enough. I just wish we had a Jeep Engineer come on here and give us the 411 on what we need to be looking for.

[rpasetto]

Originally Posted by ftodaro

I hate to over think this but its a bad habit, so my instructions For the EPS harness says that its to "dampen" the steering rack. I would think that when there is no power to the unit it would be "dampened" I assume the wobble comes from the stiff non powered rack not being able to respond or correct quick enough and that is why it wobbles, Its not a problem when going straight, it can correct and keep up, but on those sharp turns it cannot react quick enough. I just wish we had a Jeep Engineer come on here and give us the 411 on what we need to be looking for.

Actually a few FCA/Chrysler/Jeep engineers wrote the patent application back in 2012. The patent is for a software algorithm which counters wobble in the EPS computer. That same patent applies to every one of their products which have an EPS. That software is always active when you are driving down the road. The purpose of "wiring kit" is to turn on the EPS computer when you aren't driving, e.g. when you're towing. There's a lot of detail on it many threads in this forum.

[Deek]

Originally Posted by rpasetto

Actually a few FCA/Chrysler/Jeep engineers wrote the patent application back in 2012. The patent is for a software algorithm which counters wobble in the EPS computer. That same patent applies to every one of their products which have an EPS. That software is always active when you are driving down the road. The purpose of "wiring kit" is to turn on the EPS computer when you aren't driving, e.g. when you're towing. There's a lot of detail on it many threads in this forum.

Rick -

Is there any indication you’re aware of that the EPS computer stays on to prevent death wobble in new Grand Cherokee L? Someone posted on another thread that he has a GC L and in putting transfer case in neutral and turning off ignition in sequence for flat towing, the front steering remained in active state. I would then wonder if this means FCA has resolved the problem in GC L. What do you think?

There is, of course, no baseplate yet for GC L since it’s so new so it can’t yet be tried under real flat tow conditions.

Interested in your thoughts and opinions.

Thanks.

Deek

[ftodaro]

Originally Posted by deblas

Frank, I have had no luck keeping the EPS energized after placing the transfer case into neutral. I can get the EPS to remain energized using the steps provided by KYerves in post #416 but not when transfer case is in neutral. I will confirm again tonight, if your steps (transfer case then EPS harness) do keep the EPS energized.

Something I do not get is the "Service Power System" indication as noted by KYerves on #416.
Nor do I get any other indication....Do you get this service light or anything when you flip the switch with the GC running?

Deblas, I took the rig for a test run. First I switched the Jeep into Neutral like normal and let it go to sleep, then start the engine, put in the fuse and throw the switch. That does it. I tried flipping the switch and the fuse without shutting the motor off and letting it sleep and the The EPS would not engage.



So there are two things i think the written instructions have wrong.


1. that you should put the fuse in first before you throw the switch and

2. the motor has to be running when do you so.



so doing the normal Neutral change, letting it sleep and then starting and following the above order worked. I took it for a 20 min test run and it was still working and towed fine.



Next week taking a 2000 mile round trip to Acadia, i will report anything new.

[the sights]

Originally Posted by Deek

Rick -

Is there any indication you’re aware of that the EPS computer stays on to prevent death wobble in new Grand Cherokee L? Someone posted on another thread that he has a GC L and in putting transfer case in neutral and turning off ignition in sequence for flat towing, the front steering remained in active state. I would then wonder if this means FCA has resolved the problem in GC L. What do you think?

There is, of course, no baseplate yet for GC L since it’s so new so it can’t yet be tried under real flat tow conditions.

Interested in your thoughts and opinions.

Thanks.

Deek

I just got back from my dealer and yes the new "L" model with
Quadra Trac II, and with the transfer case in neutral and engine off the EPS is active (steering wheel loose) That along with posts # 425,373 & 365 leads me to believe that when the harness for the 2021 G/C (non "L"), Is installed correctly it will give a loose steering wheel with transfer cases in neutral/engine off.

I do not have my harness installed as of yet. Thanks, Joe

[rpasetto]

Originally Posted by Deek

Rick -

Is there any indication you’re aware of that the EPS computer stays on to prevent death wobble in new Grand Cherokee L? Someone posted on another thread that he has a GC L and in putting transfer case in neutral and turning off ignition in sequence for flat towing, the front steering remained in active state. I would then wonder if this means FCA has resolved the problem in GC L. What do you think?

There is, of course, no baseplate yet for GC L since it’s so new so it can’t yet be tried under real flat tow conditions.

Interested in your thoughts and opinions.

Thanks.

Deek

The "anti-wobble" algorithm in the EPS computer must be working well when you're driving down the road in all those FCA vehicles which are equipped with electronic power steering. That's the reason they developed it in the first place, for Jeeps, Chryslers and whatever other cars and trucks which don't have the vibration-damping of hydraulic PS.

Opinion: FCA/Jeep doesn't care much about those who flat-tow. Back around 2015 they were "caught" after advertising what a great RV-Towed vehicle the KL Cherokee would be (when equipped with their 2-speed&Neutral 4WD of course). I was quite flabbergasted to learn that they repeated the insanity with the updated WK2 Grand Cherokee, changed it from hydraulic PS to electronic PS.... that was the end of my thinking of getting a GC. Now, there's a three-row Grand Cherokee-L model, some of which will come off the line equipped with the 2-speed&Neutral 4WD. It sure looks like the next generation of two row Grand Cherokee (WKx? 2022? 2023?) will be modeled after the GC-L anyway. Will the wobble-debacle go away? or go back to chaos is anyone's guess.

Thoughts: Could a team of proficient engineers produce a design where the TCU computer detects that the vehicle is being towed, in neutral and rolling forward, then sends a coordination signal (a "packet") via the vehicle's CAN bus to the EPS computer which in turn activates the now-well-known and well-tested anti-wobble algorithm? You bet they could. But... is it in the marketing budget considering the percentage of WKx Cherokees projected for sale to RVers as "toweds"?

[deblas]

Originally Posted by ftodaro

Deblas, I took the rig for a test run. First I switched the Jeep into Neutral like normal and let it go to sleep, then start the engine, put in the fuse and throw the switch. That does it. I tried flipping the switch and the fuse without shutting the motor off and letting it sleep and the The EPS would not engage.



So there are two things i think the written instructions have wrong.


1. that you should put the fuse in first before you throw the switch and

2. the motor has to be running when do you so.



so doing the normal Neutral change, letting it sleep and then starting and following the above order worked. I took it for a 20 min test run and it was still working and towed fine.



Next week taking a 2000 mile round trip to Acadia, i will report anything new.

Thanks Frank, I finally got it to work with the transfer case in neutral!
I'm going to post separately, my full experience of what it took to get to the end of this "rabbit hole"!!

[deblas]

OK, first off, thanks to Boaterbob, KYerves, and Ftodaro for posting their thoughts, findings and experiences. I'd also like to thank the sights for all of the behind the scenes discussions! (I know our wives are going to be just as happy as we are that this is nearing the end!) I think this collective effort is what got me to the point of success!

Boaterbob, thanks for posting your installation process and findings; the issue you noted with the switch being configured backwards was HUGE!

KYerves, thanks for posting your updated sequence for activating this harness and what you experienced in this process. This turned out to be exactly what I came to experience after correcting a few dealer install mistakes and Jeep manufacturing/information mistakes/omissions.

Ftodaro, you posting your recent experience that echoed KYerves findings, made me dig deeper into my half-hearted dealer install.
__________________________________________________ ________________________________________
First off, as we all know the instructions and Jeep quatily control suck!
Please keep in mind that my selling dealer installed this harness, over several visits, talking with MOPAR Engineering, and never found what I'm about to share......this makes me question how much effort thay really put into getting this this working. Shame on them!

Here are some points of interest:

The switch:
As noted by Boaterbob #415, the switch may be configured backwards. Here is how to check before you install:

If mfg'd correctly, looking at the switch, you will find a keyway (an indent or indexing notch) that allows only one way installation into the red "launch" cover. If you pull the switch toward that indexing notch, you will have continuity, when pushed away from the notch, the switch is open, no continuity. That is the way it SHOULD BE.

Unfortunately, my switch like boaterbob, was configured backwards. To remedy this, I loosened the switch retaining nut, removed the red cover, then filed away the tiny notching tang on the cover base plate.
With that done, I was able to reinstall the switch 180* the other way, so that the cover could be closed while in normal drive mode.

CAN BUS Connection:
Next, I was still puzzled by why my GC never showed the "Service Power Steering" communication when I placed that switch in either position, as noted by KYerves in #416. In fact, I was getting nothing...no response, no check engine, no trouble of any kind.

OK....back to the instructions I go.
Again, with Boaterbob's comment about how a mistake could be made here ringing in my head, I double checked the connection the dealer made at the CAN BUS junction. Guess what....they grabbed the wrong bus wires!!!!!
Step 17 shows a 2-pin connector but labels it as "YL/BN", is that a Yellow and brown wire? NO! it should be labeled "YL/BN and YL".
Step 18 indicates YL/BN and YL (Yellow/Brown and Yellow are the correct 2-pin can bus wire set for this install!!) I soon found out......

At Step 17/18, the illustration indicates this is the 3rd wire set from the right, however, step 18 goes on to clarify that the YL/BN and YL wire set "MAY NOT BE IN SPECIFIED LOCATION".
Guess what....my dealer grabbed the 3rd position wire set and DID NOT VERIFY the color codes.
Now, with that said, my eyes did have a hard time distinguishing the set he pulled, even with a couple lights on in the foot well. I looked at it a couple times, thinking it was correct. Then I asked my wife to come out and take a look, thats when she suggested I take a photo with my phone....BAM...I could clearly see that the wire set was incorrect!! The dealer pulled the "YL/VT and YL" from position 3....OOOPS....the "YL/BN and YL" was in the position just to the right, I'll call it position 2.

With this new discovery, I restored the YL/VT and YL connector back to the juction block and pulled the "YL/BN and Y" wire set. This is what ultimately corrected this part of the problem!

The fuse block under the hood:
I've posted this before, but to have all in one place, I'll state it again.
My dealer interfaced with the "PK/VT" (Pink/Violet) wire at the fuse box, as listed in Step 25, however, they ultimately left it connected backwards. Which in turn, backfed the fuse box and activated the "Brake Vacuum Assist Pump"....if you have that noise.....it is wrong!

For step 26, ignore the GY (gray) wire indicated, this should be PK/VT. The correct configuration at step 26 (A & A), is with the Blue wire connected to the load side of the cut PK/VT wire and the White/Red (candy cane) wire connected to the source side (or the fuse box side).

Now on to the User Experience:

As KYerves has noted, and echoed by Ftodaro, the sequence outlined by Jeep in the user guide do not work for the GC.

I have had a similar experience as KYerves outlined on post #416 and here is what I am now going to do to set up for my tow days:
1) Connect to motorhome (tow bar and all ancillary devices), leave GC running
2) Install fuse under the hood
3) Flip the switch for the harness to tow mode, forward now in my case. This will activate the "Service Power Steering Message" on the dash cluster. Leave GC running.
3) Place transfer case into neutral (following Jeep instructions for this portion), ultimately turning the engine off in this process. With engine off, we still have energized EPS (easy steering).
4) Install braking system
5) Hit the road!

Perfect...this gets us to where we are going! Now lets talk about the end of travel day routine.....

Once we are at our destination (or have to stop for extended period), if I remove the fuse from the harness, simulating end of travel day, of course the steering stiffens and no EPS. (This is what we are supposed to do when we park over night or have extended stays with nothing charging the GC.)

Next, simulating a new travel day, presuming you did not entirely disconnect and drive the Jeep at your destination, when I reinstall the fuse, the GC steering remains stiff. Bummer!

So, to get the EPS back to tow mode for the next simulated day of travel, I found I had to go through the whole sequencing again!!......Leaving the fuse out (from the night before) and placing the harness switch into drive mode, I had to also place the transfer case back into drive mode, turn off the engine and wait for GC dash to sleep. At this point I could start the GC and with EPS returned to normal, then insert fuse, flip switch, and put transfer case back into neutral for tow mode.

It's doable....but what a bummer and a few extra steps!!

Here is my next thought on the overnight and pulling the fuse....on my motorhome, the charge line is connected to +12v all the time, not switched with the ignition on the motorhome.
If we are plugged in to shore power and the RV batteries are being charged, and thusly, the GC battery is being charged from the charge line, do I really need to pull the fuse for an overnight stay?

BTW....I placed an ammeter inline temporarily where the harness fuse goes and found that this kit draws only 150ma period. Turning the wheel or not. OK great, thats not too bad. However, my next thought is that all that is being drawn from the battery at that time?? This will be my next test.....to find out total current drawn by the system with EPS energized and GC engine off, while in tow mode. Maybe I can get to this tomorrow??

At least I can tow the GC in the intended mode (8 days from now) when we go on this trip....approx 2200mi in total.
Thanks again!

[Deek]

Originally Posted by rpasetto

Opinion: FCA/Jeep doesn't care much about those who flat-tow. .

It sure looks like the next generation of two row Grand Cherokee (WKx? 2022? 2023?) will be modeled after the GC-L anyway. Will the wobble-debacle go away? or go back to chaos is anyone's guess.

Thoughts: Could a team of proficient engineers produce a design where the TCU computer detects that the vehicle is being towed, in neutral and rolling forward, then sends a coordination signal (a "packet") via the vehicle's CAN bus to the EPS computer which in turn activates the now-well-known and well-tested anti-wobble algorithm? You bet they could. But... is it in the marketing budget considering the percentage of WKx Cherokees projected for sale to RVers as "toweds"?

All you say is right on the money, Rpasetto.

I am seriously interested in buying a new Grand Cherokee L Summit at 60K plus - don’t want a Wrangler Sahara due to truck like ride and discomfort on long road trips - and I’ve expended a lot of effort with FCA and dealers to try to get a handle on whether they have solved the death wobble problem in this new design. Is it too much to ask this question of them?!

At Jeep / Chrysler, I reached out to Steve Stander, a top customer / engineering rep whom I dealt with when I had a death wobble problem on a new 2018 Summit I bought, then had to sell for a loss. I’d like to know that in spending this kind of money again on this truly nice vehicle, I could ascertain in advance that it will tow okay without risk of death wobble.

Seems it was a wee bit too much to ask. I’ve had complete radio silence from Stander and nothing at all back from FCA. Really, the dealers don’t have a clue.

So yes, I agree with you - reluctantly but definitely - that FCA has zero investment in RV application for their vehicles.

As we’ve seen in so many other contexts over the years, money primarily seems to drive these decisions. You’d have to conclude that there are just not enough units sold to RV owners to have FCA pay attention to this issue in a real way that would solve it once and for all. That’s a real shame.

Your point is well taken: If FCA wanted to, they could easily devote a little bit of engineering effort to solve this issue for motor home owners. They could do it blindfolded - if they wanted to. For whatever reasons, they have chosen not to do so.

I have little real hope that Jeep will spend much effort or resources on this issue unless or until it involves repeated bad publicity from serious injury or death to people from death wobble collisions or significant damage to vehicles. NTSB has publicly documented multiple complaints from RV owners who have experienced death wobble in their towing situations, but nothing of any significance has come of those complaints that I can see. The ‘wiring harness’ “fix” is so complicated, so riddled with complications and so foreign to dealers (replete with incorrect installation instructions) as to be useless as a realistic means to solve the issue.

When I see folks on these forums denying that the problem exists, it reminds me of the wisdom of living in a world of ‘alternate facts’. Death wobble is a real problem, a real issue, and all of us who spend our money on these vehicles in the current state of what FCA puts out for GC owners is taking a real risk - monetarily-wise, inconvenience-wise, injury-wise. Those are the straight forward facts. Many people experience the death wobble problems, as I did; some do not. It’s still playing Russian roulette with our motor homes, our tow vehicles and our and our loved ones’ lives - a loaded gun which will in fact discharge given the right circumstances.

We all love this motor home stuff, no one more than me. It is just incredibly disappointing that we cannot find a good vehicle that we can consistently, reliably and easily tow behind our coaches to allow us the mobility we want when we travel. It sometimes makes me wonder whether going back to sailboats or motorcycles again would be safer, more fun and easier!

Thanks for your comments.

Deek

[rpasetto]

@Deek, Looking at recent FMCA and Motorhome towing guides it appears that the remaining Big-SUV alternatives for towed use are the Chev Tahoe/Suburban, the Ford Expedition/Max, their Cadillac, Lincoln counterparts or the pickup trucks from which they are derived... all in 4WD with a neural of course. I have towed my Ram 1500 pickup on occasion.

My own experience in some campgrounds with "spacious pull-through" sites has been that I'd need to disconnect to be able to park my Cherokee behind and park it across or diagonally (as I would have had to do with a half-foot longer GC). Going to a pickup or one of the Full-Size-SUVs which range two or three feet longer just further complicates the process.

Right now, I'll just "stand pat" with the Cherokee as there's no immediate need for a big capacity, three row seating toad. When the time comes, I'll start reading reviews of other towable "compact and mid-size SUV's... but the list appears to be shrinking.