NiceS4

I checked the battery and it's perfectly fine (12.5V). When I turn the ignition, nothing happens at all (no lights, etc). This all happened after I started my car this morning and then it died one second later. Is it possible some kind of relay or fuse died?

Basically I would like someone to tell me a method for finding the problem? Normally I'm pretty reliant on my VagCOM, but no power = no output.

complacentsee

You could check the fuse box for 12.5 volt to ground. I think if the central locking unit doesn't have power then the whole 12v system would be down. Same for the ECU.

There must be a Vbatt bus some where in the car, although I don't know where that would be... probably located by all the relays and close to the fuse box. I suspect it would be behind the knee bolster and behind all of the relays ect.

I really don't know much more than that. And I guessed on the location. But there must be a 12V bus bus that every thing ties to, maybe the cable has been broken loose from that.

rktskicar

Might be your ignition switch. Check it if you can, after you have checked all your fuses.

Bruce

NiceS4

What would I check for on the ignition switch? I presume it's not as simple as taking it apart and ::whoa:: I will see what's wrong with it?

rktskicar

If no fuses are blown is likely ignition switch. I do not know how to check the ignition switch. Might need to take it into a shop.

Bruce

complacentsee

You say "No power to the car" does this include keyless entry, trunk lights, lights as you open the door, clock and odometer??

If nothing works you should be able to rule out the switch.

If every thing works besides what is related to the switch, ie you can turn on the lights but the dash doesnt kick in beyond the odometer and clock when you open the door. Then the switch is the most probably culprit.

NiceS4

Nope, nothing works... keyless entry, all lights, etc... so what now?

complacentsee

Well its obviously not the ignition switch in that case. Interior lights are on an independent circuit vs the instument cluster and the locking unit. Power is not getting to the main 12V bus, or the main ground cable is not making contact with the chassis.


These bolts usually have 4 brown wires running away from them, I think there are some conventient ones located on the fire wall.

You shouild test for continuity from the battery terminal clamps. (ohm metering)

If you have continuity between the negative (-) battery terminal the chassis ground and continuity between positive (+) and the fuse box bus. Your problem could be a power cable that has failed...

I think this far uses 4 gauge wire, so it would be difficult for this to fail.. but maybe if your starter wouldn't dissengage or something I suppose it is possible...

Some where there is a master 12V bus, this is what feeds the fuse box and relays. It should have a direct connection to the batter, and some relayed connections to the alternator and starter. I think this is located behind the knee bolster as I stated earlier.

SFPinoyS4

^^^^^yup, what he said^^^

guyindfw07

What was the resolution to your issue?
My 2001 Audio TT is Dead. The right hand display says FUSE. I also checked all the fuses and the user manual nothing there.

Please help me out.

Thanks
Kirk
Dallas Texas USA
You can email me at guyindfw07@yahoo.com