dodgy 97 mistral auto

[lurcher]

So after getting my diesel pump replaced the fun continued. The auto started acting weird. First when I start the truck and pull away in D it seemed to take ages and heaps of revs to get "up on the plane" it felt like it was starting in 2nd not 1st. Then I was off fishing and stopped for a pie today jumped back in and it won't go any higher than 2nd so was having to cruise at about 90kph 3000rpm. Strangely I stopped again for about an hour jumped back in and it was normal again. Then same again stopped for an hour or so jumped back in and problem was back. After crawling along holding up the easter traffic I reached a downhill area and suddenly it started working again. I experimented by turning the O/D button on and off and it reverted to its bad behavior. Anyone struck this before?

[Crash bandicoot]

It is in limp home mode. park reverse neutral and 2nd are your only choices.

check the fuse box by your right knee when driving there is a 10 amp fuse related to the trans (it's all in Japanese so check them all)

check the harness that runs from the right hand side of the engine bay down to the auto trans. (all those plugs in the steel panel by the fusebox/power steering resivour.

check all the plugs(unplug them and check for bent pins)...
was the engine removed to do the pump or was it done in place.

From the description you have given it sounds like the auto ecu has no power or dropper resistor has been knocked damaged or the line pressure solenoid is opening at random.

[lurcher]

If it were in limp home mode surely it wouldn't spontaneously recover for a short while and then return to the way it was again? (at least if it was a blown fuse). The engine was not removed to do the pump, but I will check the pins. cheers

[Crash bandicoot]

If it were in limp home mode surely it wouldn't spontaneously recover for a short while and then return to the way it was again? (at least if it was a blown fuse). The engine was not removed to do the pump, but I will check the pins. cheers

yeah it does .lol mine did it. never knew what really caused it apart from having a blown fuse and the hold button on the dash used to flash a couple of times on start up.

[gadgetman]

Another thing to look for is the trans temperature sensor. A lot of these boxes have a loose connector, like my Safari, and it locks you out if the higher gears until it has warmed up enough. Without the sensor being read correctly it just figures you haven't got there yet. Going over a bump or slamming the door shut can be enough to make it connect/disconnect.

[Craig_D]

Having a similar issue with my R50 terrano. Drives good then gets stuck in 3rd gear. Doesn't reset until it is left to cool for a few hours. Doesn't appear to be in failsafe as lockup and overrun solenoids still work when flicking O/D on and off.

Sometimes happens after a couple of kms, other times will do 100km before faulting.

Has had a damaged planetary gear and bushes replaced, resistor put on temp sensor line, dodgy/intermittent speedo repaired and lights put on shift solenoid wires which show computer working correctly even when stuck in gear.

Likely next step is replacing shift solenoids but will look into the fuses mentioned above. Sorry to jump into thread but interesting to see similar issues.

[lurcher]

So I took the truck to an auto place he had a quick play and sent me to an auto sparky. The sparky hooked a tester up to the computer, jacked the rear up ran it, took it for a drive, scanned it twice and found that it has an electrical fault. Two fault codes are coming up it looks like both speed sensors 1 an 2 are faulty (Revolution sensor and vehicle speed sensor). There is no mechanical fault with the auto. The tester is still hooked up to the truck and I am driving it for a couple of days and reporting my findings back to the auto electrician, as what it does is it goes into a limp home mode periodically where the computer shuts down and it goes into third gear and stays there and he wants some more info on when/how often it is happening.

As I understand it at least one of these sensors is located on the top of the gear box which means they have to lower the rear gearbox mounts to access it to replace it. New revolution sensors are $400 but he told me they usually replace this one with a 2nd had one, the other sensor is relatively inexpensive (whatever that means). There is about 4 hours of work to replace the sensors. Uggh anyone struck this before and can anyone suggest a place where I could buy the sensors cheap?

[lurcher]

http://bebrs.pie-dabas.net/Webs/Terrano/R20/at.pdf

here is a handy document for the mistral auto

the fault chart in here tells me that the auto sparky is likely on the money with the speed sensor given the symptoms

and here is one for the R50 terrano

http://bebrs.pie-dabas.net/Webs/Terrano/R50/at.pdf