2003 Honda civic wiht door lock problems that only happens on the drivers side door not locking or unlocking with the key. Is this problem caused by the lock assembly or the key lock itself?

Answer 1

This problem is caused by the design of the key and the lock. The key is not open like most keys so any dirt in the opening or on the key is forced into the cylinder. If you take it to a dealer he will charge you $150+ to replace the lock cylinder. This will solve the problem but it won't be long, maybe a year or two, before it happens again. I had the driver side cylinder replaced twice and the passenger cylinder replaced once (in four years) and a year later they were both in need of repair. Then I found out that the cylinders can be cleaned for about 1/3 the cost. Of course, this savings could be partly explained by the fact that this work was done by an independent repair shop.