Volvo Repair: 94 940, light probe, belly pan

Question
Phil,  I have a 94 940 that the horn doesn't work on. I checked the fuse. Also my mechanic didn't put back the plastic cover under engine because it was torn. Is it impotant to have that on car? Is that the skid plate? THanks for your help.

Answer
The "belly pan" is there to help with aerodynamics and keeping floor clean but not absolutely essential. Definitely not a skid plate. I've thrown them away before without any problems.

Need to check power and ground circuit for horn. Locate horn and using test light, probe for pwer and ground while someone inside pressing horn. If circuit is good, horn may be bad.