A friend who is a courier and uses his TR elite for work has lost 2nd and 4th in his auto. Just wondering if anyone knows of a cheap fix, or does it look like a full auto refit?

It's gone into limp mode which means that the TCU has detected a problem with the transmission system.
Tell him to unplug the battery for 10 minutes, and then reconnect it. If it happens again he will need to take the car to mitsubishi or a mechanic that can read diagnostic codes to determine what error the TCU has found. That will then tell you what's wrong.
It could be as simple as a corroded capacitor shorting out the TCU, a sensor that has gone, worst case scenario it's new gearbox time.

He is a tightrsss everything on the Magna is second hand. He has lined up a second hand trans already or at least his "mechanic mate" has. I'll tell him about disconneecting the battery, thanks.

He is a tightrsss everything on the Magna is second hand. He has lined up a second hand trans already or at least his "mechanic mate" has. I'll tell him about disconneecting the battery, thanks.
Tell him to hold his horses, it might not neccessiraly be the transmission, the TCU/ECU's can short out and it is a pretty common occurence. Could be as simple as swapping them over. Just keep in mind though that if he replaces the transmission and it's the TCU, the problem won't go away.

Isn't the ecu and tcu in the same unit...(ecu) in 2nd gens?

Isn't the ecu and tcu in the same unit...(ecu) in 2nd gens?
Hmmm possibly, but even so the same thing can happen.

A friend who is a courier and uses his TR elite for work has lost 2nd and 4th in his auto. Just wondering if anyone knows of a cheap fix, or does it look like a full auto refit?

i'm assuming the auto is bolted to a 4cyl, if so they essentially the same transmission (just revised) as a gen1. i'm very well familiar with the gen1 autos and how they operate - guessing the same for the gen2 4cyl autos.

having said that, this is what i think is going on:
my money is on the problem lying somewhere with the kickdown drum/band. The kickdown band operates (this band holds the kickdown drum from rotating to achieve different gear ratios) only in 2nd and overdrive. It's either gonna be the band out of adjustment, the band is worn, the kickdown switch is not working, low/contaminated fluid (eg. lack of hydralic pressure). if the band is worn, needs a replacement box, or take the box apart and replace the band.

TCUs in gen2 4cyl are not learning, disconnecting the battery will more than likely do nothing. the TCU controls shift solenoids A & B... both these solenoids operate at different times, so they are working (along with the TCU) if the transmission still selects L and 3rd

limp mode is third gear only. if you select drive, and it's taking off from 3rd (ie no 1st), then the TCU either has a fault logged, the TCU is not working properly, or there is an electrical fault (blown fuse?). the reason being the way the valve bodies are designed is if the TCU is not working (eg. the shift solenoids are not working) then the fluid defaults going through the '3rd gear' circuit.

4cyl autos will have a seperate ECU and TCU.

hope this helps, sorry for the technical mumbo jumbo... just trying to explain what i think it is, and my reasoning why.