Demonix

If you have a laptop, lead and a copy of vcds or a diagnostic fault code reader or a mate with one - plug it in and scan for any errors - c6 has plenty of sensors and gadgets to go wrong so as said previously ensure all the electric toys work! - suspension at front can be vulnerable so check that and discs for signs of wear ! my 2006 c6 2.7tdi sline avant has done 106k miles and apart from a recent rear break glass sensor error is going strong - no MOT advisories at 13 years old so they are solid cars. Given age I would check that the glow plugs are all working as this can be an expensive job. I am 2nd owner as car was an ex audi dealer demonstrator and will run it until it dies as the later models feel smaller but at some point when it expires will probably get another a6 avant - have had merc e class and other german metal but really like the A6!

Hi BMW_Mania, Nope issue still present - vcds error code 01403 - Break glass sensor rear / 011 Open circuit - need to track it down to whether that's the sensor / filaments in the hatch or rear quarterlights - I stripped off the trim and had a cursory inspection of the wiring for both but couldn't see any obvious breaks or corrosion, need to get a multimeter and test the connections properly. It's an irritating problem !

Re-ran a VAG.com scan and error 01403 - open circuit on the rear break glass sensor just need to find it now....

Bump... can't be only my car that has this issue?

Afternoon fellow A6'ers My A6 alarm has gone on the fritz and now randomly goes off whenever it feels like it! I have a laptop with VAG.com and a lead, scans don't indicate any faulty sensors, battery is 100% and healthy , have checked all the catches/switches and wiring / sensors for bonnet, doors, boot lid and the windows. Had a butchers around various Audi formums and the problem may well be the alarm backup battery: - a] Not charging or able to hold charge as it's getting on for 13+ years old or b) as other A6 / A4 owners have reported the NiMH battery may have corroded and dumped corrosive shizzle all over itself and the alarm circuitry. My question is - where the feck is the alarm backup battery located? - is it in the little black bosch box in the spare wheel well next to the main battery? - just need to find it and have a look at the state of it rather than bend over assume the position and have local Audi dealer charge an inordinate sum for the same - am happy taking the thing out and fitting the circa £110.00 replacement unit myself if that is the case, saving numerous beer tokens in the process. Has any one on here had the same issue? Have used the disable sensor and tilt buttons in the mean time to prevent spurious alarm activation but wan to get this sorted asap! Thanks in advance D

Had the same issue on mine - would read 0 fuel even though just brimmed it! - quick temp fix was to pull the fuel pump fuse and the instrument cluster fuse then turn on the ignition to reset , turn off and then replace fuses then start car again - this worked for a while as a hack and got the fuel gauge registering level again but after a while issue returned ! - A6 avant has a saddle tank for weight distribution and is in the middle of the rear of the car under rear seat and boot - the fuel gauge fault is down to the 2x float sensors / sender units on left and right side under the seats - had both replaced as VAG .com wasn't 100% accurate on specifying which one - I fitted a pair at circa £78 each, now all sorted. Hope that helps