Adaptive cruise control issue

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Paul-R
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Re: Adaptive cruise control issue

Unread post by Paul-R »

There are a few links here but I have no idea whether they're still current. Nor can I corroborate whether they work.

Note that at least one site requires you register to use its facilities and is not in English.

viewtopic.php?p=834233
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson
Mesersmith
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Joined: 29 Sep 2025, 03:23

Re: Adaptive cruise control issue

Unread post by Mesersmith »

I found it on AliExpress(I don't know if this name is permitted to be write here) and I'll buy it today too see if works.
Citroen C5 Aircross 1.8 hybrid, 2021
Citroen C5 X7, 2.0 HDI, automatic, 2010

România, Călărași
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Paul-R
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Re: Adaptive cruise control issue

Unread post by Paul-R »

Why buy something that is available for nothing if you follow the links?
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson
Mesersmith
Posts: 18
Joined: 29 Sep 2025, 03:23

Re: Adaptive cruise control issue

Unread post by Mesersmith »

For two days I tried several variants and they ask for password for some files, get id for some person, other scream for some files and so on.
I don't have time to try any more.
I already pay 4 euro and I'll try today.
Citroen C5 Aircross 1.8 hybrid, 2021
Citroen C5 X7, 2.0 HDI, automatic, 2010

România, Călărași
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Paul-R
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Re: Adaptive cruise control issue

Unread post by Paul-R »

As a matter of interest, what version of Diagbox are you buying?
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson
Richard_C
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Re: Adaptive cruise control issue

Unread post by Richard_C »

I'm slightly reluctant to contribute again after the OPs initial reaction but here we go. The forum ethos is to be helpful.

Users on a Vauxhall Mokka group, same system as Citroen and other Stellantis brands, say that even a slight voltage drop on the 12v battery can stop adaptive cruise working. The car is 4 years old so maybe check battery voltage before spending too much time and money on other things.

The lack of cruise control may be an irritation but doesn't stop you using and enjoying the car. You have time to take a step by step approach.
Richard_C

Current:C4 Max Hybrid, C3 1.2 Auto
Past Citroens: Dyane (x2), 2CV, Visa, BX (x2), Xantia, Xsara Picasso, C4 Picasso,C3 (x2) C5 X7 Tourer, Synergie 1.9TD, C1
Others: Hillman Hunter, Cortina Mk1, Maxi, VWT2, Granada, SAAB 900, SAAB 9-5, R5 Gordini
Mesersmith
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Re: Adaptive cruise control issue

Unread post by Mesersmith »

Paul-R wrote: 01 Oct 2025, 07:38 As a matter of interest, what version of Diagbox are you buying?

I bought today diagbox 9.85 with 4 euro.
It doesn't worth to spend time just trying and trying different versions. Works directly in windows 10 and 11, no virtual machine needed.

I scan the car and I found enough errors, most of them temporary.

The most significant error connected with my problem, is B1209 62 Distance alert function or adaptive cruise control function information fault
But this error doesn't tell me anything, probably it is generated by another error.
Citroen C5 Aircross 1.8 hybrid, 2021
Citroen C5 X7, 2.0 HDI, automatic, 2010

România, Călărași
Mesersmith
Posts: 18
Joined: 29 Sep 2025, 03:23

Re: Adaptive cruise control issue

Unread post by Mesersmith »

Richard_C wrote: 01 Oct 2025, 15:33 I'm slightly reluctant to contribute again after the OPs initial reaction but here we go. The forum ethos is to be helpful.

Users on a Vauxhall Mokka group, same system as Citroen and other Stellantis brands, say that even a slight voltage drop on the 12v battery can stop adaptive cruise working. The car is 4 years old so maybe check battery voltage before spending too much time and money on other things.

The lack of cruise control may be an irritation but doesn't stop you using and enjoying the car. You have time to take a step by step approach.
Thank you for your answer and please, don't be mad on me, I'm just really frustrated because I bought this car for only one week.

So, about battery, I also red about this too, but I measure the battery and it has 14.3v, which is correct value.
I was thinking that maybe the value of voltage drop while car is running, but now the acc don't work at all from the moment I start the car.
Citroen C5 Aircross 1.8 hybrid, 2021
Citroen C5 X7, 2.0 HDI, automatic, 2010

România, Călărași
Minimoto
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Joined: 11 Mar 2026, 00:02

Re: Adaptive cruise control issue

Unread post by Minimoto »

Mesersmith wrote: 01 Oct 2025, 19:13
Richard_C wrote: 01 Oct 2025, 15:33 I'm slightly reluctant to contribute again after the OPs initial reaction but here we go. The forum ethos is to be helpful.

Users on a Vauxhall Mokka group, same system as Citroen and other Stellantis brands, say that even a slight voltage drop on the 12v battery can stop adaptive cruise working. The car is 4 years old so maybe check battery voltage before spending too much time and money on other things.

The lack of cruise control may be an irritation but doesn't stop you using and enjoying the car. You have time to take a step by step approach.
Thank you for your answer and please, don't be mad on me, I'm just really frustrated because I bought this car for only one week.

So, about battery, I also red about this too, but I measure the battery and it has 14.3v, which is correct value.
I was thinking that maybe the value of voltage drop while car is running, but now the acc don't work at all from the moment I start the car.
Hi Mesersmith - did you resolve your Adaptive Cruise error on your car? I have the same problem. I'm considering maybe it's either the 12V battery, but I've also seen posts that a 'bad' software update can and has caused the issue on some peoples cars.
Mesersmith
Posts: 18
Joined: 29 Sep 2025, 03:23

Re: Adaptive cruise control issue

Unread post by Mesersmith »

Minimoto wrote: 11 Mar 2026, 00:05
Mesersmith wrote: 01 Oct 2025, 19:13
Richard_C wrote: 01 Oct 2025, 15:33 I'm slightly reluctant to contribute again after the OPs initial reaction but here we go. The forum ethos is to be helpful.

Users on a Vauxhall Mokka group, same system as Citroen and other Stellantis brands, say that even a slight voltage drop on the 12v battery can stop adaptive cruise working. The car is 4 years old so maybe check battery voltage before spending too much time and money on other things.

The lack of cruise control may be an irritation but doesn't stop you using and enjoying the car. You have time to take a step by step approach.
Thank you for your answer and please, don't be mad on me, I'm just really frustrated because I bought this car for only one week.

So, about battery, I also red about this too, but I measure the battery and it has 14.3v, which is correct value.
I was thinking that maybe the value of voltage drop while car is running, but now the acc don't work at all from the moment I start the car.
Hi Mesersmith - did you resolve your Adaptive Cruise error on your car? I have the same problem. I'm considering maybe it's either the 12V battery, but I've also seen posts that a 'bad' software update can and has caused the issue on some peoples cars.

Yes, I did.
My problem was that the radar was not fully aligned and sometime works and sometime don't.
I went to the dealer, they align my radar properly, then with a tehnician from dealer went to highway and he did the procedure called dynamic calibration.
Citroen C5 Aircross 1.8 hybrid, 2021
Citroen C5 X7, 2.0 HDI, automatic, 2010

România, Călărași