woodsr1

On my 1999 Audi A4 1.8t (manual) it no longer starters or even cranks. Already replaced the starter so know it is not that. There is power to starter in the run position, but the second you turn the key to start it loses all power to the starter. No idea where to go from here, please help.

Pariah819

I think I would start by trying to turn the main pulley by hand (probably use a wrench not your actual hands). See if you can manually turn the engine to make sure its not seized up. If you can turn it then I would start checking the wiring and connections back to the battery.

twentysevenlitres

Also, there should not be power to the starter in the 'Run' position.
There should only be power to the starter in the 'Start' position.

The 'Start' position of the ignition switch does cut off most accessories available in the 'Run' position too.

woodsr1

There is power to the starting interlock relay (clutch safety relay), as well as in the ignition switch. Some how there is no power getting to the starter in the start position between the relay and the starter. Any ideas? Thanks for the help in advance

Prospeeder

Ok you say the ignition switch is getting power, but is the power leaving the switch to head to the starter solenoid?

twentysevenlitres

Does it go directly from the switch to the solenoid, or is there a relay inbetween?

Also, don't most switches on Audi's actually earth the circuits?
So the power will already be there and the switch is used to provide the earth - less arcing that way and longer switch life...

Does the ignition switch work this way?

Kovics

Woodsr1, did you ever solve this no-start; no-crank problem? Thanks.

marcus defey

If the plug ins to your main lock control vacuum module are unplugged or corroded (they can catch a lot of water in the trunk box it sits in) you will not get power to the start solenoid. I know, it happened to me and drove me crazy for a time.

Kovics

SOLUTION TO NO-START PROBLEM - IGNITION SWITCH: I had the same no-start problem as described above. To make a long story short, the root cause was the IGNITION SWITCH. After replacing the starter, PNP relay, and central locking control module, the car still did not start...even when I jumped the PNP relay. So with the ignition in the START position, I giggled the key and the car started right up. The problem was the ignition switch which wears out after 15 years.