[NigeltheBold]

I know there are many threads about FORM and what it is, and how to get out of it. I've read through several of them. And I know there are many threads about the "electric mode unavailable, cabin heating/cooling" message. But I can't seem to find anyone who has had my particular problem. It's very confusing.

I've had my 2021 Wrangler 4xe since late May. I bought it used (about 5k miles on it). My commute to work is VERY short... like 4 minutes. So electric mode was great for me during the warm months. I've also taken my Jeep on a couple of road trips, including one in early November where we drove in the mountains of NC for a few hundred miles. When we got back to southern Ohio, temperatures were starting to dip into the low 40s and high 30s. So, the Jeep started giving me the "electric mode unavailable, cabin heating/cooling" message. It would even give me the message when climate control was completely turned off. Then after a few minutes of driving (maybe 15-20), electric mode would kick-in, work for 10 or 15 minutes, then the engine would turn on again. With climate control on, it would take longer to get into electric mode. And the engine would kick back on after a few minutes anyway.

With climate control on, when I looked at the Hybrid Electric app, climate control was never using any power (0kW). So I'm wondering if I'm having the issue where the electric heater is locked and isn't working. I'm going to bring the Jeep to the dealer and ask about that (I'll bring along a copy of Star case # S2208000027).

But a few days ago, after experiencing the above problems for about a week and a half, the Jeep went into FORM for the first time since I've owned it. Temperatures started dipping into the upper 20s last week, but I'm not sure if that has anything to do with it. Yesterday, I filled up the gas tank with about 15 gallons, and we drove about 60 minutes on the highway with oil temps around 188/190. That didn't get us out of FORM, so on the way home, I ran it on the highway in a lower gear and got the oil temps up to 202/204 for about 25 minutes. That didn't work either. I'm still stuck in FORM and I've tried both solutions.

Is there anything else I should try? Do the above scenarios sound right to anyone? I can't imagine that this is how the Jeep is supposed to work... I have a dealer appointment on the 30th, and I'll mention all of these issues, but I wanted to hear from others to see what I should expect. I really don't want the dealer to tell me that this is normal behavior. I didn't mean to buy a "Summer only" plug-in hybrid.

 

[Wrangler4XEFan]

I’ve noticed there are a lot of cases where a bad ECH leads to FORM. I’ve also talked to people who were in a perpetual state of FORM that had an oil change which cleared FORM but went right in to EMU+CHOC. After they got their ECH replaced, they stopped having FORM issues too. So there’s a connection.

I’ve also talked to people who just accepted that their Jeep would be in FORM all winter. Then in the Spring, FORM cleared but EMU+CHOC showed up. The system can not display both messages. So it seems very likely that a lot of people that have accepted that FORM is just going to happen during the winter may actually have a bad ECH and may be in EMU+CHOC but they can’t see it because FORM trumps it.

 

[NigeltheBold]

Thanks. Sounds like I probably have a bad ECH then.

I was actually just driving and noticed that the vehicle is now giving me an "Oil Change Required" message (still in FORM). My oil life was at 48% before I got this message. Now it's at 0%.

Should I change the oil now, or wait until I take it to the dealer on the 30th?

 

[NigeltheBold]

Went ahead and changed the oil & filter. Reset the oil life and now I'm out of FORM. We'll see how long it lasts!

 

[NigeltheBold]

Update: took the Jeep to the dealership last week. They said they need to replace the electric coolant heater. Unfortunately they needed to order the part, and it'll take a few weeks to come in. So I'll be going back in a few weeks and hopefully they'll get it swapped out without any issues.

Just this afternoon, the vehicle went back into fuel and oil refresh mode, even though I changed the oil only two weeks ago. I've also put plenty of new fuel in the tank recently since I'm not doing much electric driving (thanks to cabin heating/cooling mode), so it's pretty clear that the faulty ECH is sending the engine into FORM.

I'll post an update once they replace the ECH. Fingers crossed...

 

[4xe2021]

Is someone (e.g. a technician, engineer, ...) able to get one of the bad heaters and check why they go bad?

 

[FireCracker4xE]

Is someone (e.g. a technician, engineer, ...) able to get one of the bad heaters and check why they go bad?

More than likely the ECH is failing due to the coolant fitting leaking. Once air is in the system the pump will experience cavitation and probably fail. Once this happens the battery compartment must be heated by the ICE heater. Make sure the dealer does a good job of cleaning up the spilled coolant from the battery compartment.

 

[4xe2021]

Thx! Where is the ECH located?

 

[NigeltheBold]

Well, this has been a nightmare. They've attempted to replace the coolant heater TWICE. Both times, once back in November and now January, they installed bad coolant heaters. I've now spent days without my Jeep because it takes a long time to uninstall/install the coolant heater and there's no way to know if it works until they have the new one completely installed. And it took three weeks for a new heater to come in. Now they're apparently ordering another one, and they "spoke to engineering" about the issue (whatever that means). I'll be taking my jeep to a different dealer. This is ridiculous.

@JeepCares this is clearly an issue that affects a lot of customers that needs to be addressed. And if you're shipping bad coolant heaters to replace bad coolant heaters, that's an even bigger problem.

This situation would be a lot easier to deal with if I could get a loaner vehicle, as I was promised when I bought the vehicle. Loaner vehicles are never available from my dealer. It's incredibly frustrating.

 

[Mllcb42]

I'll be taking my jeep to a different dealer.

Unfortunately, this is often the solution to many of these reoccurring issues.

 

[JeepCares]

Well, this has been a nightmare. They've attempted to replace the coolant heater TWICE. Both times, once back in November and now January, they installed bad coolant heaters. I've now spent days without my Jeep because it takes a long time to uninstall/install the coolant heater and there's no way to know if it works until they have the new one completely installed. And it took three weeks for a new heater to come in. Now they're apparently ordering another one, and they "spoke to engineering" about the issue (whatever that means). I'll be taking my jeep to a different dealer. This is ridiculous.

@JeepCares this is clearly an issue that affects a lot of customers that needs to be addressed. And if you're shipping bad coolant heaters to replace bad coolant heaters, that's an even bigger problem.

This situation would be a lot easier to deal with if I could get a loaner vehicle, as I was promised when I bought the vehicle. Loaner vehicles are never available from my dealer. It's incredibly frustrating.

Thank you for tagging our team. If you need support while working with your dealership or want to discuss further, send a private message.

Kate
Jeep Cares

 

[Mllcb42]

Well, this has been a nightmare. They've attempted to replace the coolant heater TWICE. Both times, once back in November and now January, they installed bad coolant heaters. I've now spent days without my Jeep because it takes a long time to uninstall/install the coolant heater and there's no way to know if it works until they have the new one completely installed. And it took three weeks for a new heater to come in. Now they're apparently ordering another one, and they "spoke to engineering" about the issue (whatever that means). I'll be taking my jeep to a different dealer. This is ridiculous.

Do you have the part number of what they replaced?

There are cases popping in where the dealer has replaced the BCH instead of the ECH and were confused why the ech still didn't work.

 

[NigeltheBold]

Do you have the part number of what they replaced?

There are cases popping in where the dealer has replaced the BCH instead of the ECH and were confused why the ech still didn't work.

I can check the reports they gave me, but I don't know if they have part numbers. Both times, they said the coolant heater is "locked" but I'm not sure which one they were talking about (old part or new part)... or which one was causing the problem (ECH or BCH). Honestly I didn't know about the BCH until now, and I still don't really understand the difference between that and the ECH. However, the dealer definitely should.

They did mention something about an updated part number when I picked it up (I spoke with the service department manager). So maybe they did get their parts mixed up. That's even more frustrating... All of this could've been avoided if they had paid closer attention and/or knew what they were doing.

They said they'll call me as soon as the part comes in and I won't have to schedule an appointment, they'll "get me right in." I'm not holding my breath. They never call when parts come in.

 

[Mllcb42]

I can check the reports they gave me, but I don't know if they have part numbers. Both times, they said the coolant heater is "locked" but I'm not sure which one they were talking about (old part or new part)... or which one was causing the problem (ECH or BCH). Honestly I didn't know about the BCH until now, and I still don't really understand the difference between that and the ECH. However, the dealer definitely should

I would be very surprised if the dealer does.

There are 3 discrete coolant loops on the 4xe (you'll notice there are 3 coolant tanks under the hood).

One is the high temperature coolant. This includes the engine, main radiator, cabin heater core, and the ECH. The ech heats the high temp coolant when the engine isn't on, which is why you get an error for cabin heating or cooling when it is malfunctioning (it is trying to heat the coolant, but can't, so it brings the engine on to do it).

One is the low temp coolant. This cools things like the electric motors, idcm, etc.

The third is the battery coolant. This has its own heater, the BCH.

This is the ECH:

This is the BCH:

Here's where it gets interesting... jeep for some reason calls the ECH the "Battery warmer" in some parts catalogs, even though it doesn't have anything to do with the battery. Further, when the ECH fails, it now throws code P0E15, which is "HV/battery coolant heater performance". If you check the PID for ECH lockout, what youre actually checking is the "HV Coolant Heater Status". A dealer might reasonably conclude (albeit incorrectly) that a code for battery coolant heater performance that requires replacement of the "battery warmer" requires replacement of the BCH.

If you did replace that, you'd quickly find yourself in the situation where things still didn't work and it seemed like you put a new, but still locked out, heater in.

 

[NigeltheBold]

I would be very surprised if the dealer does.

There are 3 discrete coolant loops on the 4xe (you'll notice there are 3 coolant tanks under the hood).

One is the high temperature coolant. This includes the engine, main radiator, cabin heater core, and the ECH. The ech heats the high temp coolant when the engine isn't on, which is why you get an error for cabin heating or cooling when it is malfunctioning (it is trying to heat the coolant, but can't, so it brings the engine on to do it).

One is the low temp coolant. This cools things like the electric motors, idcm, etc.

The third is the battery coolant. This has its own heater, the BCH.

This is the ECH:
View attachment 8935

This is the BCH:
View attachment 8936

Here's where it gets interesting... jeep for some reason calls the ECH the "Battery warmer" in some parts catalogs, even though it doesn't have anything to do with the battery. Further, when the ECH fails, it now throws code P0E15, which is "HV/battery coolant heater performance". If you check the PID for ECH lockout, what youre actually checking is the "HV Coolant Heater Status". A dealer might reasonably conclude (albeit incorrectly) that a code for battery coolant heater performance that requires replacement of the "battery warmer" requires replacement of the BCH.

If you did replace that, you'd quickly find yourself in the situation where things still didn't work and it seemed like you put a new, but still locked out, heater in.

Thank you for sharing that info. I bet that's what happened, but I'm not sure. If it's a common point of confusion, I would think Jeep would want to spread the word to their network of dealers to avoid situations like this in the future. Maybe they already have... I don't know. Maybe my dealership didn't get the memo or they're unknowingly working from outdated information. Whatever the cause, it has been a big pain. Hopefully they'll get it right next time. If not, I'll try another dealer, but who knows if they'll be any better.

 

[Mllcb42]

If it's a common point of confusion, I would think Jeep would want to spread the word to their network of dealers to avoid situations like this in the future

I'm not sure where the disconnect is. Most people seem to get the ech replaced, which to me seems like a counterintuitive part selection, so I have to assume that the documentation from jeep specifies the actual part number to be replaced and these confusion issues come up by someone searching by name rather than part number.

 

[wfesta]

Same boat as others. Car is drivable but of course I can't use Electric only. It's stuck in "Hybrid" but the Battery is barely being tapped. I was given no estimate on Wait time for part.... extremely frustrating because you spend serious (at least for me) money on your "dream" Jeep, Rubicon with all the Bells and you got a Hybrid for a very specific reason to be able to run your daily on Electric and you just can't do it...... don't even get me started on FORM. I get it I understand the parameters, but it seems to have a mind of its own.

No complaint on my Dealership or Service they seem to be at the mercy of Corporate.

From what I understand there are a lot of these. @JeepCares, any idea how long the wait for this Part usually is. Since it seems widespread there should be some data on that. this almost sounds like there should be a recall.

And I own 2 of these things..... and not feeling great about it.

 

[JeepCares]

Same boat as others. Car is drivable but of course I can't use Electric only. It's stuck in "Hybrid" but the Battery is barely being tapped. I was given no estimate on Wait time for part.... extremely frustrating because you spend serious (at least for me) money on your "dream" Jeep, Rubicon with all the Bells and you got a Hybrid for a very specific reason to be able to run your daily on Electric and you just can't do it...... don't even get me started on FORM. I get it I understand the parameters, but it seems to have a mind of its own.

No complaint on my Dealership or Service they seem to be at the mercy of Corporate.

From what I understand there are a lot of these. @JeepCares, any idea how long the wait for this Part usually is. Since it seems widespread there should be some data on that. this almost sounds like there should be a recall.

And I own 2 of these things..... and not feeling great about it.

Hey. Sadly, we don't have ETAs available to provide. If you need some support working with the dealership though, let us know.

Kate
Jeep Cares

 

[Mllcb42]

this almost sounds like there should be a recall.

Can you imagine how far delayed these would be if they were replacing all of them, not just the bad ones?

 

[wfesta]

Can you imagine how far delayed these would be if they were replacing all of them, not just the bad ones?

Agreed, what I think we will find though is there is at least a batch or two that are indeed all bad. Own two and several friends have them, I think we are at about 50%. my 22 is experiencing it, nothing on the 21 although my daughter drives that and is always in Hybrid anyway so wouldn't notice. The service department is starting to form a theory that they have been a rash after applying the RRTs and recalls. I had just had this done as well. They don't think that caused the issue but rather unmasked it but hard for even them to get feed back from engineering.