I have a Volvo Guard alarm fitted to a 1995 940, which has entered an the active-immobilised state. Essentially it has been triggered several times without the remote control fob present to enable it to be disabled. Even with the remote available, it is still not possible to disable or reset the alarm. It is also not possible to start the vehicle.

The remote control fob has been checked and is apparently transmitting.
The remote control batteries have been replaced to ensure maximum transmission signal.
The alarm has been allowed to has been allowed to trigger, run until the timer ends and the alarm shuts off. The remote key fob has then been reprogrammed to the alarm (the 5-key turn technique).

The dealer has told me that the alarm has probably locked-out and the vehicle will need to be towed in to be reset by them.

The remote control fob is the grey single button, rectangular type with the blue frequency band indicator.
The transmitter is using a UK-allocated frequency with a UK market vehicle.
The alarm has previously worked with the remote control fob, so it is presumably the correct model/type and correctly programmed to the vehicle.
The alarm has the triangular, windscreen A-pillar mounted status panel/transceiver.

I therefore have the following questions:-

1 - Is it possible to reset the alarm control unit off the vehicle?

2 - Does resetting the alarm control unit require the remote fob to be available?

3 - Is the bonnet sensor simply a magnetically operated reed switch?

4 - What are the states of the bonnet sensor with the bonnet open/closed?

5 - How do I tell if the alarm is just an alarm or an alarm/immobiliser?

6 - What are the designations of the three connectors plugged into the alarm control unit?
The top of the unit has a green 10-pin connector
The bottom of the unit has two 9-pin connectors, one pink, one black
These connectors appear to correspond to the drawing of the cabin cable harness (Part #9124692) shown in the parts catalogue.
However, the connectors do not seem to correspond to the D2 or D3 connectors shown in the main Volvo Wiring Manual, or are D2/D3 on the other end of the cabin cable harness?

7 - Was the VolvoGuard system a factory-only install, or was it also fitted pre-delivery by dealers?

8 - Were there any permanent changes made to the vehicle wiring circuits during the installation of VolvoGuard?
I.e wires cut, circuits bridged, jumpers installed, wiring changes made, etc

9 - If the alarm control unit is replaced (due to failure), do any other ECUs have to be replaced or reprogrammed to match the replacement unit?

As far as I can tell from the main Volvo Wiring Manual, US modela are basically the same apart from the D4 joint being a 2-pin connnector for the bonnet sensor/horn rather than a 4-pin and the general layout in the passanger cabin being reversed for RHD from US LHD.