I have posted before about on-going alarm problems, but thought it might be helpful if I posted separately about my findings, after I finally got around to extracting the SCU and sending it to Paul at Technozen.
The unit had clearly been removed/replaced before because a) the securing strap had been cut through and the unit was secured instead by some cable ties and b) Paul found that two of the relays were not original.
Paul replaced the other relays, extracted the EKA code, installed a new receiver to correct the poor fob range and ran diagnostics. No errors, but he found that the SCU was programmed to sound the horns rather than the BBUS siren. This, presumably, was the cause of the false alarms from the BBUS siren, which wasn't always aware of the status of the car (locked or unlocked). And he also found that the fog-lights were not enabled, which accounted for the crude after-market switch attached to the fuse-box cover. So, either the original SCU was never programmed correctly for my car, or a replacement was installed at some time without proper re-programming.
