I have a Wagon R VXI June 2008 model and had completed 30000 kms. I live in Delhi. Car is in a very good condition, but since two summers I was having a problem. In night when AC, head lights, front and rear fog lamps are on, the sound of the horn goes bleak or very bleak. When the lights or AC is put off, it comes to normal. I showed it to MASS last week. They checked it and said that the Alternator is having a problem. I got it changed. The old one was of LUCAS TVS make and the new one is of Denso. However the very night I noticed that the problem still persists. I told the MASS personal they said it may be a horn problem. Battery in my car is about 1.5 year old. I take out my car occasionally, about 10-15 kms in a week. If the battery is fine, according to you where could be the problem? Kindly reply.
Hope you are doing great.
Trying to relate to your problem, i too have faced the same kind of problem whilst driving my father's Honda City..
But the real catch here is, it used to get normal after a couple of honks..was surprised for couple of instances..post investigating, found out that this happens when the exterior of the horn gets a little moist..Aslo check for the battery life..
So what i urge you to check is:
Trust me this is definately not a problem, is a small check that has to be done. Nothing related to the alternator i guess..
I agree to ur point if the battery is fine, things should be in place..
Get the electricals checked by an auto-electrician (yes, there are auto-eletrician specialists too)They readily troubleshoot rather than just replace random partsI had the same issue in my Esteem, MASS was never able to fix it.