Juryokun

Hello everyone,

First post here so hello. Posting because I was on the way home in my 2003 Audi A6 3.0 Quattro that I had recently purchased, while on the way home, the car cut off completely and I had to pull to the side of the road. All of my lights stayed on with the key in the ignition, but when I went to turn it on, I wouldn't get anything and all my lights would turn off. Then after a few tries I eventually got some kind of clicking noise. After getting this a few times, I started to get nothing again. A gentleman ended up stopping who tried switching out my battery and hooking up a jump pack to it. When we did that we got nothing when we attempted to start the car, just interior lights with the key in the ignition. Any form of help would be greatly appreciated as this is my first Audi. Thanks!

turbo510

First, try to get the fault codes read out, and post what you see.

The lights turning off during a start attempt is normal, if you mean the headlights. If everything including the dash lights go off, that isn't normal. The problem sounds obviously electrical, so some basic checks are necessary. You said that the interior lights will come on. With the ignition switched ON, the headlights should come on too when you move the light switch to ON- do they? So no starter motor clicking when you try to start the engine, correct? No sound of the starter running? How about the headlights, do they dim when trying to start, or stay bright?

How about the instrument lights, which should include all warning indicators when the ignition is switched ON. If not, the problem could be the ignition switch, but I would suggest you find which fuse if for the engine's computer (ECU) and measure between it and grounded metal. With the ignition switch turned to ON (or RUN) position, you should get the same voltage as the battery. The fuses have small openings in them, to allow the pointed probe of a Voltmeter to touch the metal fuse material. Check at both holes, in case the fuse has blown, in which case only one hole would find battery voltage. But even a good fuse doesn't mean the ECU is powered:

My A4 developed a thing where going over speed bumps would cause the engine to briefly loose power, and put the engine in a low-power limp mode. In this case I am pretty certain that it was a defective ECU relay, which I found had a very marginal connection between contacts when powered. The relay is in the black ECU box under the hood, beneath the transmission controller and the ECU aluminum enclosures, along with the fuel pump relay and a couple of others. Probably more work than you want to get into, but I suggest that in case you have no power to the ECU, which you can suspect if the code reader cannot connect with it.