ECM, PEU, TCM Update

A

AlexB1988

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ZS Hybrid+ Trophy
Hi all

As promised in another thread I'd update when any progress is made with MG in regards to solving the over-revving issue.

So while I myself didn't get very far with MG head office who are being very careful not to admit problems and advertise the ludicrous over revving as a "characteristic" of the car (like 5000 rpm going 50mph uphill is just a quirk), my dealership have been pushing them and I'm not the only one to report the same problems. It's a big priority for the dealership who I want to reiterate have been absolutely fantastic.

My car was given to me with the PD052 update already completed. A semi-related issue for those without the update is the lack of power in the vehicle when the battery is low. My belief is this update fixes that and kicks the engine in when battery is down to around 30% charge rather than the 10% that is the case without the update. So I've had no such issues with lack of power upon acceleration and confident that update is therefore successful, if we accept the update is not to fix the over-revving.

The dealership have in the last few days received some update/guidance to try and address the over-revving issue, and that is to do an update to the ECU, PEU and TCM. I'm not technical and have no idea what they are so I'm hoping somebody on here may know. I'm informed that MG do acknowledge there is something that needs doing, but by the wording of the email the dealership read to me, they are saying it's on the basis of improving driver experience rather than rectifying a fault, which to my mind is to limit liability for car rejections etc. They say it causes no damage. I did point out the vehicle guidance states not to take the revs above I think 3000, but the car does not behave in a manner that allows that, and just today I was driving along at 60 and within a second it decided to go from around 2k revs to 5k revs in about 2 seconds with no additional acceleration or hill.
On the same journey I went up a 1/4 mile hill at around 40mph and had to keep letting go of the accelerator as the revs were continuously at between 4k and 4.5k revs.
It will be doing damage to the engine, and will be affecting the mpg figures that really is the ultimate aim of having a hybrid. I would argue the the PD052 update that dictates an earlier battery charge will affect mpg as well, maybe negligible but a negative all the same.

I'll let you know how I get on but for anybody affected (I imagine all) please contact your dealer and mention this.
 
I wonder if the three speed gear box is the problem? Not exactly an easy fix.
 
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Hi Mickel

I think the 3 speed gearbox probably is a mistake, but really if the balance is right with the battery input providing half the power, then up to 70-80mph then based on a standard fuel car I believe in theory it should be OK as the 3 gears essentially have to cover 35-40mph of it. If that makes sense. Like gears 2, 4 and 6 on a standard manual.

But I agree, 3 provides limitations both in terms of at higher speed, and switching options at higher revs, and at least a 4th would help.
 
Torque converter issue? But then some people in this forum are saying the PD052 issues solves the high revs issue. I wonder if two things are going on? PD052 prevents battery depleting to low. Can understand how this will have an impact on revs. All good. But… there are still some people saying they’ve had PD052 update and they’re are still experiencing high revs.
I test drove the car twice and there was a lot to like. But I experienced the high revs and only ok fuel consumption. Test drove Hyundai Kona twice and experienced no such problems and 63mpg. Same route. In the end I opted Kona and sacrificed some luxuries like heated seats / steering wheel / 360 camera……
But my main decision for deciding not to opt for MG was….. total lack of response to numerous emails that I sent to customer service, head office…….
“Looking in to ways to improve user experience” and similar such phrases rings alarm bells. Apple used such phrases when they mass released an iPhone on the market only to realise it had antenna issues. I know…. I worked for them.
 
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Agreed, it is poor from MG. I get why they are saying it from a defensive commercial position and potentially legally also, but it isn't acceptable. The PD052 from what I understood today rectified the low battery and thus low power issue, which apparently my car has had and I have not encountered such problems. The ECM PEU TCM update (not assigned a PD number as it stands) is I believe to rectify the revving somewhat. Which hopefully it does otherwise I am going to get into legal territory with MG. I fundamentally disagree with their position that the issue to be resolved is driver experience/satisfaction related as opposed to damaging to the engine the MPG and resulting future value of the vehicle. As well as embarrassment driving past fellow school parents on the school run up a hill at 4000 revs!
 
I sincerely hope the update solves your high revs issue and it doesn’t turn out to be an issue that can’t be resolved by an update. As for being embarrassed…. where I live, driving anything under £80000 is reason to be embarrassed! 🤣
 
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AlexB1988 said:
Thanks, I hope so! Haha you in Marlow or something? I'm in West Yorkshire so most things are cheap (because we don't like being ripped off), stolen or on credit!
Click to expand...
I do genuinely think that if MG sort out their customer service and maybe just put a little bit more care and attention into their releases….. they will annihilate most European manufacturers when it comes to value for money. I think they are improving rapidly. I’m under no illusion that European means better. I think even some volvos are almost fully manufactured in China. Toyota has some models (I think) manufactured in China.
I was just a little nervous this time around and I particularly liked certain features of the Kona. Felt like Hyundai had thought more about the practicality of driving. Thought Kona would be less annoying to live with day to day. I could be proven wrong!!
But I was mostly very impressed by the MG ZS Hybrid +. People automatically trash Chinese manufacturing … but the reality is, loads of companies are turning to China for complete manufacturing or manufacturing of major components. I’ll watch this forum with interest, because the MG ZS was genuinely a nearly for me. Lots to like.
 
AlexB1988 said:
Thanks, I hope so! Haha you in Marlow or something? I'm in West Yorkshire so most things are cheap (because we don't like being ripped off), stolen or on credit!
Click to expand...
I do genuinely think that if MG sort out their customer service and maybe just put a little bit more care and attention into their releases….. they will annihilate most European manufacturers when it comes to value for money. I think they are improving rapidly. I’m under no illusion that European means better. I think even some volvos are almost fully manufactured in China. Toyota has some models (I think) manufactured in China.
I was just a little nervous this time around and I particularly liked certain features of the Kona. Felt like Hyundai had thought more about the practicality of driving. Thought Kona would be less annoying to live with day to day. I could be proven wrong!!
But I was mostly very impressed by the MG ZS Hybrid +. People automatically trash Chinese manufacturing … but the reality is, loads of companies are turning to China for complete manufacturing or manufacturing of major components. I’ll watch this forum with interest, because the MG ZS was genuinely a nearly for me. Lots to like.
AlexB1988 said:
I like the Kona too
May I ask what the self charging hybrid version closest equivalent list price is to the ZS Hybrid trophy? Struggling to find it.
Click to expand...
oh you’d be talking £10000 more I think. To get all the stuff the MG has. Blind spot monitoring, heated seats / steering wheel, 360 camera……..
but if you paid for top end Kona you’d also get things like Bose sound system and other high end luxuries.
But even the basic trim Kona has most driver assist features. It’s other things though that persuaded me. I prefer the placement and software of the infotainment system in the Kona. It’s higher and angled towards driver. I preferred the sound insulation in the Kona. The rear suspension was better in the Kona. (my opinion). The stereo was better and had EQ(again subjective). It felt better to drive, hardly ever seemed to rev above 2500 and if it did, it immediately dropped back to 2000. Felt the auto gearbox was better and I suspected the car was dropping into EV mode more often than the MG.
The general feel of the MG interior I really liked and in some ways, is better than the basic spec Kona. But… once I drove both cars, I personally preferred the Kona. Just seemed more customisable and better thought out. But that’s just down to preference. MG is incredible value for money.
 
AlexB1988 said:
Hi Mickel

I think the 3 speed gearbox probably is a mistake, but really if the balance is right with the battery input providing half the power, then up to 70-80mph then based on a standard fuel car I believe in theory it should be OK as the 3 gears essentially have to cover 35-40mph of it. If that makes sense. Like gears 2, 4 and 6 on a standard manual.

But I agree, 3 provides limitations both in terms of at higher speed, and switching options at higher revs, and at least a 4th would help.
Click to expand...
I think the 3 speed gearbox is not necessarily the bottleneck. Honda uses an in principal similar setup, with a petrol engine and a more powerful electric engine doing most of the driving, and the battery not being bigger; I however just has one speed for directly driving the wheels, a direct gear for the motorway.
I think the bottle neck is more the generators 45kW max output, which at certain speeds, where the engine revs would not find an ideal pairing in one of the gears, has not enough output for decent performance once the battery is low. The Honda system has IMO a much more powerful generator, thus never has the problem that the electric engine has too little power at disposal.
In a Toyota eCVT (which is not a classic CV, but planetary gears), you can, if needed, at least use maximum petrol engine power at all speeds, even if it means the engine screams away like in those 50cc scooters (and even there you do feel once the battery is empty, though naturally, thanks to the different gearbox/generator setup, less so).
I think MG tried to solve this issue with the size of the battery, which works well in 95% of the cases, but as we experience, not always. PD052 apparently improves things, but naturally, this setup will have limitations at some points. In case of the MG, it certainly is the size of the generator, which is on the small size for a full hybrid, especially for one relying more on the electric drive than say a Toyota. Another reason I think there are high revs is that the system tries to feel very potent, much less rubber band than the typical Toyota, but that means that the system sometimes unnecessarily keeps the engine at higher revs for maximum torque, especially when using MG pilot. This could certainly be rectified with software updates, at least for normal and ECO mode.
One thing though, as I have already driven quite a few full hybrids form several car makers: Hybrids will occasionally rev quite high, without an immediately apparent reason, especially when coming from a manual car. That is as specific max efficiency is at max torque, and thus also best for charging a battery.
 
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Just arrived at the dealership for this update. No rev on the regular hill, no revs above 2.5k all the way, EV mode at 70mph and 65mpg start to finish. They are going to find no fault 🤣

Apologies missed your messages Mick and Mickel. Will respond later on
 
AlexB1988 said:
Just arrived at the dealership for this update. No rev on the regular hill, no revs above 2.5k all the way, EV mode at 70mph and 65mpg start to finish. They are going to find no fault 🤣

Apologies missed your messages Mick and Mickel. Will respond later on
Click to expand...
I was going to suggest hitting it with the branch of a tree Basil Fawlty style. Looks like you won’t have to. Maybe your car sensed what I was going to suggest! Keep a branch in your boot going forward from now.
 
Tempting but would invalidate the paint warranty haha.
So 2 hours on the update and unfortunately had issues on the motorway on the way back, decided when accelerating from 60 to 70mph to go to 5k revs. Also noticed battery going lower than usual.
By the time I got to my regular hill the battery was well charged and it stayed in EV up it to the end (usually kicks in to petrol half way up) so don't have a like for like comparison there yet. Will test it later.
So I'm not sure if any improvement has been made, the motorway suggests not. Also worried it has overridden the PD052 update of not allowing battery depletion.
 
I've given it pretty much a couple of weeks. I'd say there has been a little improvement but certainly not to where you would expect it to be. Have been keeping in communication with the dealership and been advised to speak to the finance company and obtain an independent evaluation as to vehicle suitability. I'll be doing that in the coming days, but no idea what the turnaround time is, has anybody done this before?
 
My dealer emailed me today to confirm the update was applied on Friday (Shrewsbury)
"The PD052 update is to two modules. This update is to update the PEU and the ECM. The ECM was already upto date so we only had to apply the PEU update - this is the PD052 update."
I have responded that the car continues to over-rev and lose power. I will be attempting to video the issue this Friday when I return to Shrewsbury.
 
Hi


Yesterday, I received a set of updates for my ZS.
I picked up my car on December 16th, and until yesterday, it hadn’t received any updates.
The updates I got are: PD033 (FICM), PD050 (FVCM), and PD052 (ECM & PEU).

So far, I’ve driven about 100 kilometers with the new updates, including around 10 kilometers on the highway at speeds between 130-140 km/h (I’m from Poland, where 140 km/h is legally allowed).

My impressions are very positive.

Highway driving:
At the mentioned speed and distance—on flat roads without hills—the battery level never dropped below 2 bars. In manual mode, the car drove confidently and without any issues. However, when switching to MG Pilot, the car downshifted, and the RPM increased to around 4100 rpm. When slowing down to around 130 km/h, MG Pilot maintained 3rd gear with correct RPM levels.

Before the update, I had to be very careful with the accelerator pedal, as the car would constantly downshift, and the RPMs would skyrocket, making it feel like the engine was about to explode. Also, the battery would drain to just 1 bar.

City and suburban driving:
The car feels completely different—much better in terms of drivetrain behavior.
The biggest improvement for me is during dynamic acceleration. When pressing the accelerator about 3/4 of the way down, the car accelerates more briskly, and the RPMs don’t exceed 3100-3200 rpm.

It seems like the fuel consumption has increased by about 0.5L/100 km with a similar driving style. Of course, I haven’t driven much yet, so I’ll keep monitoring it.

For now, I’m as happy as a kid because, in my opinion, the powertrain tuning has significantly improved. It's like drawing a different car than before the update.
 
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PD052 does exactly what it is intended to do,if only MG dealerships in the UK would come clean and admit that the update is necessary.
 
Nico said:
My dealer emailed me today to confirm the update was applied on Friday (Shrewsbury)
"The PD052 update is to two modules. This update is to update the PEU and the ECM. The ECM was already upto date so we only had to apply the PEU update - this is the PD052 update."
I have responded that the car continues to over-rev and lose power. I will be attempting to video the issue this Friday when I return to Shrewsbury.
Click to expand...
So one of two things can be deduced. The high revs are due to something entirely different or the dealership don’t know how to apply the update correctly. Since there are people on this forum who have had PD052 update and it’s solved the issue…. I can only assume the dealership you went to doesn’t know how to apply update correctly?
Just to add… YouTube channel Webby On Cars reviews the car…. check out 11:28 onwards ….. exactly what I experienced during two test drives. It’s weird, because when I test drove and the high revs occurred, the actual noise from the engine suggested higher revs than the 4500 it was indicating. Car was screaming at certain times …. and I was convinced the noise would be indicative of higher revs than the 4500 I was seeing.
Anyways…… love to know once and for all if this is just a software update issue or something else….
 
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I had the PD052 update, in the UK, nearly two weeks ago and it definitely hasn't resolved my over-revving issue.
It seems that the update has worked for some on this forum but not for others.
Perhaps, it's possible my dealer hasn't installed it properly (as Mickel suggests) but is that likely? - surely they would easily identify failed software?
I really enjoy the car and have driven 3500 miles, averaging 55 mpg and rising. 99% of the time it's a comfortable, smooth, ride but even in the last week -
1. Several times it has inexplicably started revving around 3500+ on minor inclines. It holds the excessive revs until I decelerate.
2. On the M54, on an incline, I started overtaking a van at approx 68 mph. As I drew level the revs went over 4000+ and I had to decelerate which wasn't great given I had several cars behind me also looking to overtake the van.
The dealer says they cannot recreate the over-revving, so the onus is on me to prove it by video evidence. I've tried but it's virtually impossible as some days there is no over-revving. Plus my wife isn't too happy leaning over, trying to video on her mobile, every time we hit an incline.😁
 

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