One problem related to battery has been reported for the 2003 Audi A4. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Audi A4 based on all problems reported for the 2003 A4.
1. The events leading up to the failure: Audi A4s have an intake plenum drain grommet located near the battery; this funnel is known to become clog due to debris and grime. The drain grommet on my vehicle became clogged some time ago and I did not become aware of this problem until the funnel stopped working and allowed water to drain inside my car. This caused my comfort module to fail - my power windows, power locks, interior lights, keyless remote entry, alarm, trunk, battery and gas tank lid ceased to function. 2. The failure, how often it occurs, its consequences; and, Audi of America knows about this problem. This problem is pretty common in the 2003 Audi A4s. If you do a search about it online, many consumers are affected by this clogged drain grommet. Upon doing more research, I was shocked to learn that the 2002 Audi A4 models had exactly the same problem, but had its vehicles recalled. 3. What was done to correct the failure; I. E, parts repaired or replaced (and if old part is available) I brought my 2003 Audi A4 to the dealership (Audi of hawaii) to correct the problem, which cost me $1400. The technicians replaced the plenum grommet drain, comfort module, battery, and had to clean the bottom interior of my car which was saturated with water, mold, and mildew. I also wrote a letter to Audi of America and Audi of hawaii to address this problem to other 2003 Audi A4 owners since it was addressed for the 2002 Audi A4 vehicles. Their reply was that since it had not been federally mandated they will not have a recall for the 2003 Audi A4.