Rover 200 & 400 Owners Club

Welcome back to the driving seat.

Great to hear that you're sorted - many would have given up...

A fault finding chart resulting from this detailed investigation would be invaluable to the club members

indeed John, however with all due respect, sometimes we tend to drift away into complex situations for not thinking straight, sometimes faults can be very simple and we end up like stripping half a car. Not knowing where things are in a car for example is what made me search for the 5as Alarm module right the way into the boot, having to strip out boot linings, passenger and drivers inside sills covers, trying to trace a Black/red wire which ended up going into boot lid, and still could not trace any sign of the 5as module, eventually with everyone's help and particularly BB's help who pointed it was sited under the dashboard drivers side well above the area where the fuses are, but indeed stuck to the underside of the dashboard, almost in a horizontal plane.

In short, always better to check door looms, but they are not easy to check, not at all, the rubber housing on the loom is so tight, it cannot be drawn back enough even to repair the broken wire, and let us face it if the wire was broken, you may not actually see it split in half, it may still look intact from the outside and yet its inner copper conductors are snapped underneath the insulation covering, I have come across such like broken wires many a times.

Yes it can be summed up in a little flow chart like method, logically what needs to be checked before ending up stripping half your car for nothing, when all that is preventing your alarm operation and keyfob sync problem is a broken wire in a door loom.In very rare circumstances it can be a fault with your 5as Module itself, and not ruling out micro switches, as these cam all be tested from the drivers door .

However, problem comes, how do you find the broken wire, and which one is the culprit as there are several wires from the 5as unit to the drivers door, 6 to 7 wires that one of them can break and cause all sorts of misleading conclusions.
1 wire carries common Ground
1 wire carries barrel switch status (For determining if doors are being opened manually by your ignition key, and not by your remote fob)
2 wires carries door lock position determination (Up or down) (unlock or locked position)
2 carries central locking motor current ( current flows momentarily in one direction to lock and reverses to unlock, current only flows for a limited time not lasting more than about 2 seconds, enough to allow motors to run to lift door locks, then both wires are grounded to car earth)

and of course there are other wires for other things like for windows opening or closing, side mirror control, etc. though not related to Alarm setting.

Such a pain that the door and tailgate hinge looms did not have a connector at each end, so they could be worked on at the bench. They are actually an extension of the main body harness, which makes repair such a pain. Even if the plug had been placed on the body instead, you'd have the option of withdrawing the flex part back into the door (with trim card removed) to gain more free length to play with.