ACC System Unavailable

I went away for 6 weeks over Christmas, came home to a flat battery. When the battery was replaced, the 'ACC not available' message did not show, the cruise control was working and I cancelled the booking I made with another MG Service.
The radar unit isn’t powered by the 12V aux when ready, it’s supplied by the CCU. When the battery went flat and was replaced, the car did essentially a ‘hard reset’, looks like a 12V disconnect would have sorted that…
 
The radar unit isn’t powered by the 12V aux when ready, it’s supplied by the CCU. When the battery went flat and was replaced, the car did essentially a ‘hard reset’, looks like a 12V disconnect would have sorted that…
So why didn't the fabulous Motorama MG team in Moorooka do that for me in 5 minutes and charged me $20 instead of $447 and not willing to give me any redress???
 
So why didn't the fabulous Motorama MG team in Moorooka do that for me in 5 minutes and charged me $20 instead of $447 and not willing to give me any redress???
I’d say they never thought of it as it’s probably not written in the manual?

Go back to them in person and ask to speak to the service manager, then explain the situation and ask him why their lack of common sense should leave you out of pocket?
 
I’d say they never thought of it as it’s probably not written in the manual?

Go back to them in person and ask to speak to the service manager, then explain the situation and ask him why their lack of common sense should leave you out of pocket?
Been there, done that, in writing. They have denied it in writing. So I'm telling the world. Don't go to Motorama MG in Moorooka. They claimed that the radar was damaged and if I brought it back it would cost at least $1,000 with no guarantee of it calibrated.
 
Hey

I have done a few charges now on AC and DC. When I first start the car after each the message “ACC System Unavailable” pops up then goes away and everything works as normal.

I have the MG5 Trophy LR.

Anyone else seeing this?

Many thanks
Hi

Did you get fix for this issue? I've this message come up suddenly and no cruise control & related function is working. Is there an obvious known fix?
 
Hi

Did you get fix for this issue? I've this message come up suddenly and no cruise control & related function is working. Is there an obvious known fix?
A ‘hard reset’ (disconnect the 12V aux for a few minutes) has sorted many issues.
 
I do get an: “ACC system unavailable” message that comes up for 1.2 seconds and that is immediately replaced “Service Soon”. The car has 24000km so service is a while away yet. MG service here suggests cleaning the area in front of the camera used for ‘Adaptive CruiseControl’ to see if that fixes it. The Adaptive Cruise Control is not actually having any issues. It responds to changes in speed of cars in front just fine. Nevertheless I will try cleaning the windscreen infront of the camera as advised.
 
I do get an: “ACC system unavailable” message that comes up for 1.2 seconds and that is immediately replaced “Service Soon”. The car has 24000km so service is a while away yet.
Looks like the dealer never cleared the service counter during the first PM??
MG service here suggests cleaning the area in front of the camera used for ‘Adaptive CruiseControl’ to see if that fixes it. The Adaptive Cruise Control is not actually having any issues. It responds to changes in speed of cars in front just fine. Nevertheless I will try cleaning the windscreen infront of the camera as advised.
In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?
 
My MG ZS EV 2021 started showing 'ACC not available' message a few months ago. Sent it to the MG Service and they said that a camera under the bumper was damaged, they tried to calibrate the camera for a whole day unsuccessfully, charged me $447 with no result. The car was driveable, just no cruise control. I went away for 6 weeks over Christmas, came home to a flat battery. When the battery was replaced, the 'ACC not available' message did not show, the cruise control was working and I cancelled the booking I made with another MG Service.
Thanks for sharing. Sometimes actual issue reason is not known. I had same message and MG dealership did not want to cover this in warranty & asked for a large sum to replace full camera unit. I showed it to a friend and all it was a loose bracket holding camera which when tightened, fixed the issue.
 
Looks like the dealer never cleared the service counter during the first PM??

In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?
Interesting. According to MG: “ Adaptive cruise control works by using a laser, radar or camera system. This is usually mounted within the front of the vehicle and will constantly scan the road ahead for other vehicles and monitor their proximity to you.“
It is unlikely that ACC would rely on radar alone. The behaviour of phantom braking etc esuggests to me that the top camera is an integral part of the way ACC and emergncy braking works. It would make sense if the systems are fully integrated.
 
Looks like the dealer never cleared the service counter during the first PM??

In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?
Interesting. According to MG: “ Adaptive cruise control works by using a laser, radar or camera system. This is usually mounted within the front of the vehicle and will constantly scan the road ahead for other vehicles and monitor their proximity to you.“
It is unlikely that ACC would rely on radar alone. The behaviour of phantom braking etc esuggests to me that the top camera is an integral part of the way ACC and emergncy braking works. It would make sense if the systems are fully integrated.
This forum will NOT let me reply to the post you originally made. so……..
 
The behaviour of phantom braking etc esuggests to me that the top camera is an integral part of the way ACC and emergncy braking works. It would make sense if the systems are fully integrated.
You’re correct, the ‘Driver Assistance System’ makes use of the full suite of sensors. However ACC is one particularly function that’s not possible without measuring the distance to the car in front of you, a MG5 uses a radar unit for that purpose but I can only assume the MG4 is does same?

Point is that the dealer’s advice to ‘clear the windscreen in front of the camera’ is therefore unlikely going to solve an ‘ACC not available’ problem…
 
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Looks like the dealer never cleared the service counter during the first PM??

In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?
Looks like the dealer never cleared the service counter during the first PM??

In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?
Looks like the dealer never cleared the service counter during the first PM??

In a MG5 ACC is controlled by a radar unit, would be surprised if your MG4 is using a camera instead?

You’re correct, the ‘Driver Assistance System’ makes use of the full suite of sensors. However ACC is one particularly function that’s not possible without measuring the distance to the car in front of you, a MG5 uses a radar unit for that purpose but I can only assume the MG4 is does same?

Point is that the dealer’s advice to ‘clear the windscreen in front of the camera’ is therefore unlikely going to solve an ‘ACC not available’ problem…
Thanks for the reply. I never expected it would fix the problem (but I would be happy to be proved wrong).
BTW: I have had the MG long enough to identify some interesting quirks in the safety systems. It has favourite bends in the road nearby, where it becomes cautious IF there are a specific set of circumstances. If there is a whole line of cars coming the other way, it recognises them as oncoming traffic and we continue on at the cruise control speed. If there is only one car coming and we are not part of a string of traffic on our side, it will ease off the throttle and watch. The speed drops about 10Kmh before it decides to return to 80Kmh. That is clearly a combination of sensors not just radar. It is a left hand bend about 4km out of town.
I expect this ‘ACC System Unavailable’ warning to continue for sometime. It reminds me very strongly of the sort of engineering/software issues I encountered off and on during my years as an IT manager. It’s a combination of the algorithm and the hardware plus the limits of the testing and development cycle. In summary, you cannot test for every single possible circumstance and solve all of the possible issues.
It is no coincidence that my choice of camera brand is the one which issues regular firmware updates rather than the one which never does*. (It releases a new model) OR the one which reluctantly does issue updates but often suddenly has to withdraw the update because it makes things worse**(much worse).
Eventually EV companies will adapt and fall into one or other of these camps. (* Sony, **Canon)🥴😡🤬
Fortunately for me the MG glitch (ACC S U) is a minor error which just puts up a warning.
Hopefully this is all it will do.
In the meantime, I WILL CLEAN the area in front of the camera AND the area in front of the main (?) radar sensor in the center of the front below the MG logo and number plate in the grill area. (It makes no difference so far ). Maybe after a drive or two.
Hopefully this will make it MUCH easier to provide feedback to the company and dealerships.
My theory is that all systems have limitations and so I sort of enjoy the chance to chat about ways to cope.
🫣😵‍💫😳😬🤪😁😁😁😁😎
 
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