20 reg VW TRoc numerous faults showing
Discussion
DILs TRoc gave up on her at work last week, numerous faults (7) showing. RAC changed the battery.
1.5 petrol DSG.
She got home but is still showing several faults but when his code reader is plugged in there are no fault codes showing.
Faults showing on the central display (ignoring the bonnet open because it was) are:
- tyre pressure loss indicator
- cornering light
- start stop system
- ABS/stabilisation control (ESC)
- hill hold assist
- Front assist unavailable.
Those are not hearsay as I am with the car now. They don’t appear immediately but shortly after ignition is turned on.
There is another that shows occasionally but I haven’t see it - yet
Have an appointment at VW next week but she doesn’t want to drive the car, any suggestions?
1.5 petrol DSG.
She got home but is still showing several faults but when his code reader is plugged in there are no fault codes showing.
Faults showing on the central display (ignoring the bonnet open because it was) are:
- tyre pressure loss indicator
- cornering light
- start stop system
- ABS/stabilisation control (ESC)
- hill hold assist
- Front assist unavailable.
Those are not hearsay as I am with the car now. They don’t appear immediately but shortly after ignition is turned on.
There is another that shows occasionally but I haven’t see it - yet
Have an appointment at VW next week but she doesn’t want to drive the car, any suggestions?
DIY OBD hand held.
Just spent 10 minutes looking around the car for fuses/connections and noticed a Spedal plugged in. It gives a wireless Apple CarPlay connection, the standard car is wired CarPlay.
Unplugged it and turned the ignition on - no faults. Several cycles - no faults. Plugged it back in and started car - no faults.
The car was showing faults before the battery was changed so could the failing battery have caused the spedal to upset the system and unplugging it has reset it? Will get them to drive the car over the weekend and see how it goes.
Just spent 10 minutes looking around the car for fuses/connections and noticed a Spedal plugged in. It gives a wireless Apple CarPlay connection, the standard car is wired CarPlay.
Unplugged it and turned the ignition on - no faults. Several cycles - no faults. Plugged it back in and started car - no faults.
The car was showing faults before the battery was changed so could the failing battery have caused the spedal to upset the system and unplugging it has reset it? Will get them to drive the car over the weekend and see how it goes.
Stepdaughters Nissan had a similar catalogue of warnings a few months ago.
The wire from the alternator was breaking at the connector. Not the main one that charges the battery but a small wire that goes to the ECU and is clearly used by the car to enable / disable systems depending on 'battery' voltage.
Fixed the wire - all errors disappeared.
The wire from the alternator was breaking at the connector. Not the main one that charges the battery but a small wire that goes to the ECU and is clearly used by the car to enable / disable systems depending on 'battery' voltage.
Fixed the wire - all errors disappeared.
Not been driven (well a few inches - blocked in) but just turned the ignition on and faults showed, tried again with CarPlay adapter plugged in and no faults, three more times with and without adapter no faults. Looks like it is going in to VW.
Will have to get a video of the faults showing as you can bet that they won’t occur while VW have it.
How do you tell if an ABS sensor is failing?
Will have to get a video of the faults showing as you can bet that they won’t occur while VW have it.
How do you tell if an ABS sensor is failing?
Your cheap OBD tool probably only has the ability to talk to the engine ECU. There are many ECUs on a modern car. If you don't have the required equipment you won't be able to read the fault codes stored on them.
You need a better code reader. Once you have that you will be able to determine what the car 'thinks' is wrong and why it is generating a fault code.
As mentioned above, a common cause of the symptoms you describe is often lack of signal from an ABS sensor. There's no way to know for sure without further investigation.
Your options are effectively:-
1. Buy a better code reader, learn to use it and investigate the fault yourself (remembering that the ABS ECU recording an ABS sensor fault does not mean you have an ABS sensor fault).
2. Give car to garage to sort.
3. Replace parts based on hope that you will fix the fault without causing more (unless you go to the OE for parts this almost always leaves the car more broken than when you started).
With the type of questions you are asking I would suggest option '2' is the way you should go.
You need a better code reader. Once you have that you will be able to determine what the car 'thinks' is wrong and why it is generating a fault code.
As mentioned above, a common cause of the symptoms you describe is often lack of signal from an ABS sensor. There's no way to know for sure without further investigation.
Your options are effectively:-
1. Buy a better code reader, learn to use it and investigate the fault yourself (remembering that the ABS ECU recording an ABS sensor fault does not mean you have an ABS sensor fault).
2. Give car to garage to sort.
3. Replace parts based on hope that you will fix the fault without causing more (unless you go to the OE for parts this almost always leaves the car more broken than when you started).
With the type of questions you are asking I would suggest option '2' is the way you should go.
IJWS15 said:
How do you tell if an ABS sensor is failing?
Because you'll that exact set of warning lights on the dash. 
A decent OBD scanner shouold be able to tell you which wheel sensor has the problem.
They're not expensive, and difficult to change. Any garage can do it for you.
Edited by silentbrown on Friday 28th August 13:56
New battery doesn't mean a good battery, fitted byRAC doesn't inspire confidence lol.
Did they try to jump start it?
Whenever multiple faults show like this it is normally a voltage issue, can happen even if the battery starts the car.
Jump starting can cause issues too.
All sounds electric related.
Did they try to jump start it?
Whenever multiple faults show like this it is normally a voltage issue, can happen even if the battery starts the car.
Jump starting can cause issues too.
All sounds electric related.
Richard-D said:
Your cheap OBD tool probably only has the ability to talk to the engine ECU. There are many ECUs on a modern car. If you don't have the required equipment you won't be able to read the fault codes stored on them.
You need a better code reader. Once you have that you will be able to determine what the car 'thinks' is wrong and why it is generating a fault code.
As mentioned above, a common cause of the symptoms you describe is often lack of signal from an ABS sensor. There's no way to know for sure without further investigation.
Your options are effectively:-
1. Buy a better code reader, learn to use it and investigate the fault yourself (remembering that the ABS ECU recording an ABS sensor fault does not mean you have an ABS sensor fault).
2. Give car to garage to sort.
3. Replace parts based on hope that you will fix the fault without causing more (unless you go to the OE for parts this almost always leaves the car more broken than when you started).
With the type of questions you are asking I would suggest option '2' is the way you should go.
I used to do all my own car maintenance/fixes ( short of welding) when the cars were out of warranty but have had three leases and our current car is still in warranty so not done anything for a while.You need a better code reader. Once you have that you will be able to determine what the car 'thinks' is wrong and why it is generating a fault code.
As mentioned above, a common cause of the symptoms you describe is often lack of signal from an ABS sensor. There's no way to know for sure without further investigation.
Your options are effectively:-
1. Buy a better code reader, learn to use it and investigate the fault yourself (remembering that the ABS ECU recording an ABS sensor fault does not mean you have an ABS sensor fault).
2. Give car to garage to sort.
3. Replace parts based on hope that you will fix the fault without causing more (unless you go to the OE for parts this almost always leaves the car more broken than when you started).
With the type of questions you are asking I would suggest option '2' is the way you should go.
1 - it is my son’s reader, I still need to look at the suppliers website to check what it will do.
2. - Expensive and slow, the quote they have is just to diagnose!
3. - VAG don’t make many parts themselves so those from a reputable supplier are likely to be from an OEM supplier and if they don’t fix it he can put the originals back.
stevieturbo said:
And did the RAC man not check and clear codes after fitting the battery ?
Does it have a battery monitoring system that needs the battery coded to the vehicle ?
I would make sure the battery is coded before chasing anything else, modern charging systems will think it still has the old battery which was toast, then it won't charge the new one correctly.Does it have a battery monitoring system that needs the battery coded to the vehicle ?
ARH said:
stevieturbo said:
And did the RAC man not check and clear codes after fitting the battery ?
Does it have a battery monitoring system that needs the battery coded to the vehicle ?
I would make sure the battery is coded before chasing anything else, modern charging systems will think it still has the old battery which was toast, then it won't charge the new one correctly.Does it have a battery monitoring system that needs the battery coded to the vehicle ?
I cleared the error codes
Changed the battery
Coded it in using serial number 111111111
Then when I started the car I was still getting error messages so turned the steering wheel full lock each way (as per some advice I found on the internet) and then had no issues whatsoever.
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