Hal_TT::CBP

trying to determine if my going battery is due to leaving the rear reading lights on for 3 days(thanks to my 2yr old daughter for that one) or possibly from some electrical short that I may have in the ABS/ESP system.

Went to start the car this morning(sitting since Sunday morning) and it will not turn over more than a few times - drained battery, ok. Check all the lights and the two rears are on, source of drain I guess. I check for DTCs after the joke post today and find a few:

- Driver Door Sensor, alarm triggered something. This one may have been there for a bit.

- IC intermittent communications errors with radio(normal for my car)

- and this one which I haven't seen before:

Tuesday, 12 July 2005, 10:01:44
VAG-COM Version: Release 504.1-UD
Control Module Part Number: 8D0 907 389 E
Component and/or Version: ABS/ESP allrad D56
Software Coding: 04395
Work Shop Code: WSC 06435

1 Fault Found:

01435 - Brake Pressure Sensor 1 (G201)
35-00 - -

I clear it and let the car sit all morning(lights off). By 1-2PM it has enough charge to turn over and start. I let it run for 30min and shut it down. Come back and check it again at 4:30PM and it barely turns again, sets the 01435 DTC again and finally starts. I go get a battery for it but haven't installed it yet.

My question is: is this DTC the cause of a dead/dying battery or is the battery dying because of the DTC? Have run through the Bentley testing on the ABS/ESP modules and all display group blocks(on 08 basic settings) clear except Test Table 04 which has "invalid" in block one(for brake temp standing time)...

"invalid" says "there is an open circuit between IC and ABS module" - OR -

"battery disconnected or completely discharged" - which makes me think it has a high amperage link to the elecrical system and is either draining it or b!thing because of it. I searched and found an A8/S8 with intermittent 01435s but nothing else.

Just want to chase other possibilities before installing the battery and having something dischare it with a short or other failure occurring(had ths happen on a 340 Mopar where the volts gauge would show 13-14v charging but the altenator was not, ignition system chewed through 2 new batteries before I caught the altenator).

TIA...

Rory

the cheapest repairs you can do. I'd start with that and see if the codes go away. If not, you have your next lead to follow up.

Rory

Hal_TT::CBP

Crawled through everything again last night with more charge on the batt and determined its going. New battery is in and all seems well so far today. Had to modify my bracket but luckilly there are 3 additional nut/bosses under the batt on my car to screw into. That and some roto-zip action on the bracket halped make it universal. Sears "International" batt saved me 10lbs and cranked the CCAs to 770A. Nice mod I guess.

Funny thing too is my fading FIS display is normal now(mostly). still has a few lines of fade at initial startup but normalizes quickly.