1995 525i alarm/horn relay question (help!)

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I did some searching, but couldn't come up with anything similar.

I have a 1995 525i with the factory alarm/Keyless entry system. The system is currently configured to use the car's horn rather than a separate alarm siren. Everything has been working flawlessly until a day or two ago when the horn just stopped sounding upon lock/unlock/double lock actions. The system still works just fine otherwise and the horn still works when I push the horn button on the steering wheel. Further, I popped up the back seat and located a relay that happily clicks away when I arm/disarm, as if it's trying to signal the horn but it just never gets there.

Anyone ever have this issue before?

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I'm also getting sporadic issues with the interior lights not coming on when I disarm. Somethimes they do, sometimes not. grrrr.

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Well, I located the problem, figured I'd post it here for future searches.

I determined that the horn trigger wire under the back seat (black w/blue stripe) was getting a signal from the alarm/relay, so I decided to try to locate the factory alarm horn. I had no idea where it was, but with the help of the e34 electrical diagram I found it - it's in the cowling at the base of the windshield on the passenger side. I had to remove the screws holding the insulating panel behind the engine to the firewall and carefully pull back the passenger side corner of it to access the horn. This is the panel with the large electrical harness attached to it running horizontally behind the engine. With the number of wires/hoses in the way, it would have been pretty damned tough to remove it completely, but pulling back the passenger side corner of it gave plenty of access. I then undid the connector at the horn and hooked up my voltmeter to it and saw that it was indeed getting voltage when I armed/disarmed the system. On a whim, I reconnected it and suddenly the horn started working again.

Maybe it was simply a dirty connection or perhaps a sign of the horn itself dying, but for now it works and I know exactly where to look next time. I hope this helps someone in the future. (I'm still having sporadic issues with the interior lights, but I'll live with it.)