ĤELP! Front assist unavailable, ACC unavailable etc

[Smileysmile]

2 weeks ago the yellow triangle popped up on my dashboard.

Stop/start, front assist unavailable, ACC unavailable.

I had just driven back from a lovely bbq.

2023 T6.1 with LV bodykit, air suspension.
Fitted a year ago and I've had no problem until now.

I purchased the Carista plugged it in. Tried resetting faults. I've attached the data. Feed back would be much appreciated.

 

[Kind of Blue]

Wheel sensor?

 

[Smileysmile]

Wheel sensor?

The wheels have been off on the rear and the front passenger side. Fluid was leaking from the washer bottle area. I investigated. Last week vehicle had its first service. Leak was resolved by VW on warranty. They weren't instructed to find the errors, as that's money. They would investigate if requested on another occasion. They initially said due to body mods this could be the cause.

I told them they were working fine a year after mods. Bloody sensors.

In what way would wheel sensors be the cause? *baffled*

 

[Kind of Blue]

The wheels have been off on the rear and the front passenger side. Fluid was leaking from the washer bottle area. I investigated. Last week vehicle had its first service. Leak was resolved by VW on warranty. They weren't instructed to find the errors, as that's money. They would investigate if requested on another occasion. They initially said due to body mods this could be the cause.

I told them they were working fine a year after mods. Bloody sensors.

In what way would wheel sensors be the cause? *baffled*

I am guessing from the problems that I have encountered, I have had 4 wheel sensors replaced. Also there are loads of posts covering the issue That is why I put up the ? question mark. Not an expert, far from it but getting to spot some of the questions and statements posted on here I understand that other systems rely on wheel sensors for information. It is a common problem that throws up a host of ills. It can be intermittent also and then just fail. can still drive but ABS is affected cruise, and loads of other things. The real experts will take a view and give there advice or and diagnosis. Best to have it scanned either by your self a friend or a garage. That will give a definitive diagnosis. I understand that VCDS is the favoured tool. I do not own one so have no idea what to do with it

 

[Smileysmile]

I am guessing from the problems that I have encountered, I have had 4 wheel sensors replaced. Also there are loads of posts covering the issue That is why I put up the ? question mark. Not an expert, far from it but getting to spot some of the questions and statements posted on here I understand that other systems rely on wheel sensors for information. It is a common problem that throws up a host of ills. It can be intermittent also and then just fail. can still drive but ABS is affected cruise, and loads of other things. The real experts will take a view and give there advice or and diagnosis. Best to have it scanned either by your self a friend or a garage. That will give a definitive diagnosis.

If you mean scanned by diagnostic I used the Carista. I didn't read wheel sensors but ABS came up. Would this mean the wheel sensors have been disturbed as I've taken the wheels off? I can see me having to take it to the garage *rolls eyes*

 

[Smileysmile]

From the data, it seems communication is broken between sensors.

 

[Kind of Blue]

If you mean scanned by diagnostic I used the Carista. I didn't read wheel sensors but ABS came up. Would this mean the wheel sensors have been disturbed as I've taken the wheels off? I can see me having to take it to the garage *rolls eyes*

I would wait to see what the others on here have to say. I am old but a novice. My analogy to modern vehicle electronics is ,, remember green scree computing in the work place? A million years ago Awkward comercial programs where written for managing stuff. It could be found every where from military to public library, local government to the NHS and probably everywhere else too. Every new source taking it up would need to adapt it to run a new service. It would need loads of test runs before coming on line and the Jo Blogs would stuff it up by just asking it the wrong question or holding a key too long. The latter I know because when these dreadful things came in all staff where given instruction and encouraged that you can not hurt it, go on anything you like...OK I held a key too long and it crashed a huge server..The computer experts where a vision first of not understanding then realisation and urgent calls being made by flustered computer nerds flapping around . The system was down more than most of a day shutting every one out for miles around. Great fun. I think that car platforms originally had a system and similarly each vehicle variant has to have additions to an old system. So half the things being plugged into the system at inception in development has to be worked in and it throws faults and hissy fits until the stem is developed to work and released to the public and this goes on for years until a new platform is presented and it all starts again. Its an imperfect thing that has been stretched and adapted to work with modern requirements. Quite a few on here can do the routine and a little more but there are also a few geniuses and someone who is right at the top of the game and that is, mmi a member with profound knowledge and ability at this stuff. I am only used to third world vehicle really, old LR Ex military vehicles ect so it is all eye popping stuff to me. Ido pick up on trends though.

 

[Pauly]

Ignore the missing message faults they are erroneous, no comms to the radar is prob the root cause and seems the most logical as this would also cause the cruise error

If you are going to try and fix it yourself then I guess the radar would be the first place to go and check the connections/wiring etc but that’s bumper off to get at it properly

 

[Kind of Blue]

My guess was wrong have to go back to school.

 

[Smileysmile]

I would wait to see what the others on here have to say. I am old but a novice. My analogy to modern vehicle electronics is ,, remember green scree computing in the work place? A million years ago Awkward comercial programs where written for managing stuff. It could be found every where from military to public library, local government to the NHS and probably everywhere else too. Every new source taking it up would need to adapt it to run a new service. It would need loads of test runs before coming on line and the Jo Blogs would stuff it up by just asking it the wrong question or holding a key too long. The latter I know because when these dreadful things came in all staff where given instruction and encouraged that you can not hurt it, go on anything you like...OK I held a key too long and it crashed a huge server..The computer experts where a vision first of not understanding then realisation and urgent calls being made by flustered

Ignore the missing message faults they are erroneous, no comms to the radar is prob the root cause and seems the most logical as this would also cause the cruise error

If you are going to try and fix it yourself then I guess the radar would be the first place to go and check the connections/wiring etc but that’s bumper off to get at it properly

Oh gawd! Interesting that radar connections would be suspect as they haven't be disturbed by me.

 

[Smileysmile]

What about disconnecting the battery for an hour and checking fuses?

 

[manfrotto]

Oh gawd! Interesting that radar connections would be suspect as they haven't be disturbed by me.

Maybe the sensor is just dirty/obstructed?

 

[Smileysmile]

Maybe the sensor is just dirty/obstructed?

The one at the front, Radar, is clean. I'm always washing my van

 

[manfrotto]

As previously mentioned faulty wheel speed sensors can create spurious errors:

Thread 'Front assist & ACC unavailable'

29 Jan 2023

I am on my way back from Skye. My ACC has been working fine but has now started throwing up the above errors and the cruise control is inactive.

The roads were very bumpy. There are no errors shown on the Carista.

Is there anyway or process to get it sorted or is it a dealer job.

I did take out the £38 a month extended warranty so I’m thinking it is covered.

Edit: I just found this.

• Mick
• Replies: 20
• Forum: Vehicle Faults, Warranty Repairs Issues & Problems

• 

 

[Smileysmile]

As previously mentioned faulty wheel speed sensors can create spurious errors:

Thread 'Front assist & ACC unavailable'

29 Jan 2023

I am on my way back from Skye. My ACC has been working fine but has now started throwing up the above errors and the cruise control is inactive.

The roads were very bumpy. There are no errors shown on the Carista.

Is there anyway or process to get it sorted or is it a dealer job.

I did take out the £38 a month extended warranty so I’m thinking it is covered.

Edit: I just found this.

• Mick
• Replies: 20
• Forum: Vehicle Faults, Warranty Repairs Issues & Problems

• 

So, investigate the wheel sensors? Dirty sensors? Or disturbed sensors?

 

[Pauly]

No i wouldnt bother, if they were the issue it would show on a fault scan and tell you which one
You central issue is lack of communication with the front radar, clear the fault and see if it comes back, if it does fix that first or chasing of the tail will commence !

 

[Smileysmile]

No i wouldnt bother, if they were the issue it would show on a fault scan and tell you which one
You central issue is lack of communication with the front radar, clear the fault and see if it comes back, if it does fix that first or chasing of the tail will commence !

I agree, the scan doesn't mention wheel sensors. I read somewhere to reset the ECU. Disconnect the battery and cross a jump lead from negative to positive for 10 seconds, reconnect battery and this might reset all the connections.

 

[Smileysmile]

13 out of 13 faults