Thanks for the reply Joy,
I have put a code reader onto the system which comes up with nothing. I used a D-CAN GT1.INPA reader with compatible BMW software which comes up blank. I have also bought & plugged on a different ECU & TCU with no changes to the readings or light illuminations.
There doesn't seem to be power at Terminal 15 of which I am not sure what this refers to. I have found that the Relay for Terminal 15 is under the Electrical Component ECU & TCU Box in the Engine Compartment. I have swapped out this relay which made no difference.
I will get hold of the relevant schematics in order to find out where the feed comes from to the Transmission Position Switch. The schematic for the 95 model says that the power for the Transmission system comes from Fuse 22. I do have four cables with power going into the TCU.
I will go to ALLDATA.com & see what I can get there to have another go at tracing the wiring today. I will let you know how I get on,