I finally bit the bullet the other day and bought myself VCDS to tinker with the cars. I was out checking my Superb for a few things and then decided to try something simple to break my VCDS virginity. I decided to enable footwell lighting in my Superb. 

 

I get the guide from here and go through it all and methodically check every step. I enable the function; switch the car off, lock and back on to add the adaption. All fine, turn the ignition on and after 30 seconds I am bombarded with several error messages on the dash AFS not available, EML light etc. I poop my pants at this point thinking what had I done!

 

I tried to start the car and it just made a furious clicking noise and no engine start.....ohh no!

 

I admit my heart was in my mouth thinking I'd seriously cocked something up. I reconnected VCDS and did a scan; 13 errors inc controllers that couldn't be found and errors on others! 

 

I open one that is showing an error and look for the error message - battery level low 8.6v. Odd I think; I'd only been out in the car an hour earlier and it started first time on the nose. 

 

I get out my DMM and measure the voltage and sure enough it's 8.6v. I disconnect it from the car and it rises to 11.4v with no load. Clearly not happy.

 

I go and check ECP and Halfords for battery prices as I need the car that afternoon. £60 odd quid for a Duracell 5yr battery will do nicely. I go back to the battery and measure again and it's risen to 12.2v! Bouyed by this I try one last time (with the DMM attached to monitor during cranking). It drops to 4.05v when cranking   Definitely a dead battery then!

 

I get the new battery; fit, clear error codes and she's been happy ever since!

 

Certainly an interesting introduction to VCDS 

I've had a similar experience.

 

A Brisky member came round to my house for me to do some VCDS tweaks. He was fitting a new CAN gateway so we swapped it over then coded it in and did a couple of other tweaks.

 

All fine and we shook hands and he got back in the car and I went inside.

 

A minute later a knock on the door "the car won't start!"

 

An "oh dear... what's gone wrong moment" occurred... but the first thing we thought we'd try was a jump start so I pulled my car round and hooked it up and it fired straight up! Phew!

 

I genuinely was worried for a minute thinking I'd broken his car! lol

When one is going to do long diagnostic sessions with the electrics on, first turn off everything in the car that is not needed.  Second if it is going to be more than 10 -15 minutes, connect a good battery charger. 

 

The draw on today's cars is quite high.  You can't run the electrics long without a charger!

Edited 4 February, 201610 yr by bearthebruce

Battery was 8yo so I should cut it some slack. There was no evidence of it dying up till that point, which is why it caught me by surprise!

Well, you know what they say: you always remember the first one .