Hi all so I have a 2010 sline manual Q5 which recently has started displaying some warnings. The lights are ABS and ESP along with warnings for handbrake malfunction and headlight range control. The handbrake is electric and still.worls fine.

I have opened the computer box under the right wiper and had the mother board and the fuse tray out and all dry with no perished cables I also swapped relay 643 with the one in the boot to see if this helped but nothing. I don't have Vagcom or anything but did have someone plug in a universal OBD reader but no.fault.codes were found it advised.

The car drives fine but has the dash lights on and is due it's MOT at the end of September so really need to get this sorted.

Can anyone help or advise anywhere good I can take it to locally.

Thank you 

Hello Chris from the Homeland,

How old is the battery and what make is it?

Such symptoms can very often be due to simply a a substandard battery - now beyond its sell by date. 

Kind regards,

Gareth. 

Hi Gareth,

So this morning the fault lights all went off. We used the car to go shopping to several shops and then parked it back up on the drive all was ok. Then this evening I had to pop out and as soon as I started the car all the faults came back. I'm unsure of the age of the battery or make it was on the vehicle when i purchased it 2 years ago.

I have a month until my MOT so need to try and resolve this. Will Carista be able to read the codes for this fault do you know?

Thank you

Chris

 

 

Hello Chris,

These vehicles are controlled by so many electrical associated components, all of which demand near to peak performance to ensure they don’t throw up fault codes. 

Obviously it’s your call, but with an ‘unknown make’ battery which has been on the car for over two years, then my reaction would be to simply renew it - even as a hedge against future issue due to its deteriorating condition. Of course, you can spend money on expensive diagnostics, and probably replacing  culprit components shown as fault codes. 

If it were mine, I would first treat it to a new Varta/Bosch battery with at least a 4 year warranty - available on line from specialist suppliers such as Tanya, Battery Megastore etc. - most delivering to your front door. Personally, I would not fit any alternative makes. 

Kind regards,

Gareth. 

Hi Gareth 

Thank you in will have a look at that option and get some prices. Just had a quick look and batteries for it seem to range from £150 to £580 based on the registration so need to check what it has on it in the morning I think and maybe get a load test done on the battery.

Cheers

Chris

 

 

Hello Chris,

What site were you looking on for those prices? 

What would be useful would be to get whatever information you can off your existing battery. Info. would include aH rating, CCA figure (cold cranking amps) and a fair idea of the dimensions in mm. Be very careful to avoid any contact with a battery terminal if using a steel tape! 

Load test? Yes, maybe helpful, but late models (your?) can be fitted with a battery monitoring unit which does just that, and although the battery may be deemed reasonably OK via. a load (drop) test, it might not satisfy the limits that the BCU has and certain functions like stop/start will start to shut down, and warning light circuits also become troublesome.

Obviously Chris, no one can diagnose the issue without the car, but on an economics basis, it can sometimes make sense to spend money on changing a battery rather than diagnostics. 

Worth trying EBay for prices, since the major suppliers tend to advertise there and offer free delivery via. that route.

The price range you are getting sounds high unless this is a very large battery.

Kind regards,

Gareth.