Reboot Computer Services 106 Walcot Street Bath BA1 5BG 01225 447227 firstname.lastname@example.org
Hincot Ltd. registered in England and Wales Co. reg. no. 483 8381 VAT reg. no. 811 3624 64
In the last episode of the saga the cruise control actuator was reconnected to the throttle so, imagination fired, attention was focussed on the controlling end. Mindful of the brake switch fault previously reported the relevant bits of wiring diagram were downloaded from Alldata and studied. The V8 has the normal brake light switch that operates the brake lights but also an extra switch that connects the cruise control and one of the gearbox controller connections to earth via the bulb filaments until the brake is depressed. This was adjusted to give a more reliable contact. Attention was then turned to the column switch wiring after an hour long attempt to find the cruise control module -
The said volts come from a particular fuse via a distinctively coloured wire which had 12 volts at the fuse and nought volts at the column switch. I did try to trace the wire but gave up after another fruitless hour. On closer inspection the same volts were also supposed to be on another gearbox controller input but weren't there either. Same coloured wire. Sod it I thought -
The bad news was that the graunching and ratchetting now happened all the time. At this point SJM (thanks again Scott!) suggested that applying the brakes would disable the diff lock and, indeed, if the brake was lightly depressed in a tight turn the ratchetting stopped. Obviously one of the switch functions .. I subsequently found the same information in the owners handbook. Should have R'd the FM!
It is at this point in the story that an explanation of the UFO brakes is required. Audi refers to these as "internal caliper" brakes and explains that having the disk mounted at its circumference on a steel basket thing with the caliper working from the inside of the disk increases both swept area and working radius thus increasing the possible braking effect by a considerable amount. The V8 and the S6 were fitted with these devices. Subsequent models were fitted with 16" wheels which made the UFO design unnecessary. Unfortunately it is not possible to pop round to your local motor factors for cheaper brake rotors. Happily, Audi will supply new rotors for the sum of £125 or so each plus VAT (actually not a bad price considering their design) and you do see part worn ones on Ebay.
Why UFO? a look at the rotor will provide the answer.
One of the things that the Audi owner has to do from time to time is to replace the panel lights. This is generally acheived after removing the intrument panel with varying degrees of difficulty depending on the model. Being only familiar with the larger models I can say that the A6 was easiest because the wheel tilt was adjustable and the 100/200 harder because the steering wheel has to be removed. The V8 is not bad except that all the bayonet fittings on the left hand warning lights are broken and so have to be re taped into position on reassembly. At least GSF and Euro Car Parts keep cheap lamps these days -
These days the bulbs can be fitted for a much more reasonable £7.00 or so. Whilst doing the bulb bit to the V8 I thought that the calibrated dials on the fuel and temp gauges from the spare instrument panel would look better than the plain ones fitted. Fine, I'll just switch the gauges, I thought but finding that the readings on the gauges were completely different and having no wish to find out why I ended up just switching the dial faces. I still had the fuel gauge reading slightly wrong due to the gauge not quite meshing with its adjuster properly on reassembly.