When I first got my 122 about 4 years ago, I used the ignition key to open the door, and I thought that the second key was for the trunk. But when I went to the locksmith to get copies made he told me that the trunk key is also for the doors and that the only reason why my ignition key opened my doors was that the locks were so worn out. I found that the he was right and the trunk/door key works much better at opening the doors than my ignition key. If your door locks are worn out enough your ignition key might be working fine. Have you tried your trunk key on the doors??