Gq not selecting 3rd or 4th gear

[Brandon.W2004]

Hi all, just wondering if anyone has got any suggestions or knows the likely problem to what I have.
So currently I've got a 1992 gq tb42efi patrol auto, and It goes into 1st and 2nd perfect, I have just had an auto electrician check the ecu and tcm which they have conducted a full continuity test and have not found anything wrong with any of the wires, it been looked at by auto mechanic which have checked the mechanical side of the auto even putting it into lymph mode and thats when the transmission went into all the gears. They found nothing mechanical that is causing the issue.
What does anyone suggest I should do next?
Thanks for your help in advance

[mudnut]

How old is the transmission fluid? What colour is it? Does it smell burnt? Maybe it needs a service. Never a flush. Just drop the oil pan and change out the filter then put it together and fill it with new fluid. Or get a mechanic to do it if you are not confident to.

[mihit]

I must misunderstand...
"Limp mode" is normally what RESTRICTS you to lower gears... So if it went into all gears IN limp mode, sounds like a couple of wires crossed. Blocking solenoid stuck on... or selector solenoid not letting go.

Someone will surely know, but the whole box is controlled by 3 or 4 solenoids, and gears are selected by engaging various combinations of those solenoids. There was a crowd somewhere in straya that somehow "manualised" auto boxes.
If I was any use I'd remember, but it might rattle a brain cell in someone else...

(I don't deal with autos so this is just brain fart)

[mudski]

There was a crowd somewhere in straya that somehow "manualised" auto boxes.
If I was any use I'd remember, but it might rattle a brain cell in someone else...

Wholesale Automatics I would assume is the crowd you are thinking of....