Audi Repair: Audi Security System, doubt in my mind, turning the key

Question
QUESTION: Hey there. I have a 98 audi a4 i just bought the other day. I drove somewhere yesterday, parked it, tried to get something out of the trunk and i heard a little alarm sound. When i came back to start it, it will not start. I believe it is a security issue. There is a brand new battery in there. all the lights come on. I have been told to get out of the car, lock the car and unlock it to enable it. I have tried with no luck. Can you give me any suggestions?
Thanks in advance.

ANSWER: It sounds like perhaps the alarm has malfunctioned...  Although, does the engine turn over, or does turning the key just not do anything?  If you get something out of the trunk when the car is locked (using the remote) then once you close the trunk the alarm will re-set (short chirp from the horn); that is normal.  If you then unlock the car, the alarm is switched off. That is also normal.  There may be another reason for your no-start.  Let me know,  Jan

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QUESTION: Thanks Jan. But my car does not have a remote. When you turn the key, no noise come out of the engine at all. All the lights come on and you here the sound that comes on whenever you put your key in the ignition. It was kinda hard for me to open the trunk, so i guess the system assumed that someone was breaking into the car. I have read somewhere that there is a relay that goes to the starte that can solve that. I don't know anything about those electricals unfortunately. I already disconnected the battery and let it sit out and connected. But still, nothing. It is very
frustrating. I have no doubt in my mind that it is the cars security system. I mean the key turns all the way like you will normally start a car. But no crank, fire, or whatsover. no sound out from the engine. but all the lights come on. Any other suggestion? Thanks in advance.

Answer
This could be a fault with the park/neutral switch.  It could also be the starter.  Check that you are getting 12V at the starter when the key is turned.  If you're getting 12V there, then the starter is bad. If not, we can start going back to the various modules.
Let me know what you find,  Jan