Ute is gettin old

Took the ute for a service
D & M Mechanical in Spine St.  $313.50

It had developed a problem where as one drove it would change gear somewhat randomly.  There is a LCD display on the dash that would flick back and forward between Drive, Neutral and Reverse.
On occasion it would simply indicate Drive irrespective of the position if the gear shift leaver.
In that scenario, switching OFF and on would clear the fault.

I thought that perhaps the transmission was out of oil.
There is no filler cap for the transmission oil.  You have to put the vehicle up on a hoist and undo bolts 
Dave (The D in D & M) was somewhat skeptical (rightly so) that that the oil had ever been changed.  So he took the bottom off the transmission and cleaned it out and replaced a filter and of course put in new oil.  Problem was still there.

He recomended taking the vehicle to a automatic transmission specialist.  So I made an apointment and called in on
Highway Auto Transmission in Murial Ave Moorooka.
They took it for a test drive.  Observed the problem and figured it was the selector switch.  Quoted $220 to replace it.  Ouch oh ugh I though but accepted the quote. 
This was a while you wait thing.
Vehicle put up on the hoist and the switch was dutifully removed and replaced.
While it was up on the hoist, They showed me the connection to the gear box.  There is a cable that comes from the gear shift leaver and mechanically tells the gear box what gear to go into.  This is detected by the switch that was being replaced.  There are also another 8 wires that come in / out of the gear box.

I do not quite understand this because it seems that irrespective of what position the selector is in, the computer can still tell the gera box to go to another gear.  Why not simply send the selctor into the computer and the have the computer set the gears.  It would be just as unreliable.

Back down off the hoist and off for a test drive. 
Problem still there.
"Sir you had better go see an auto electrician"
"Are you sure I asked"  Still thinking that actually the problem was a lack of oil pressure inside the unit.  And somehow wishing to get some tangible benefit from these guys for my $220. 
"Definitely an electrical issue"  Was their response. 
"Well could we just put the old switch back on and drop that $220 by the cost of the switch" I ask.
"No charge sir we did not fix the problem"
Whats that I.  Did I feint or something.
No charge.  You have gotta be kidd'n me ....
The fellow reiterated.  No charge because they did not fix the problem.
I insisted on at least giving the $50 for the time spent.

Then off to the auot electrician
Coopers Plains Auoto Electrical 3275 2166 Rory
They quoted $105 scann fee to plug their OBDC scanner on and read an dclear some codes.
 Then I would come back in a week or so and they can have it for a day. 
Took it over.
As I was driving over it was doing teh problem a lot.
Got there and when Rory took it for a drive with me in the passenger seat it hardly missed a beat but luckilly it did get the display stuck in park at the end. 
Rory wiggled some wires and the problem seems to have gone away.