The official way to start diagnosing the Jatco (and most auto's) is to measure all sensors and solenoids when cold. Also check the level of the auto fluid. Changing the auto fluid has worked wonders for some on the Jatco but I don't think it will fix your problem on this occasion. I would hope the garage carried out a gearbox oil change when they changed the solenoids as it doesn't cost much and is quick to do if they're working on it anyway. Reading the error codes is always good but on Freelanders yer need to read the engine, auto and abs computers as they all play a part in the process of the auto functioning correctly. Engine computer requests gear change. Auto computer carries out the gear change. ABS provides feedback signals.

As said above there's a few parts which can crack causing loss of pressure of auto fluid, which causes loss of drive. In this situation the auto's computer see's the electrical signals it's monitoring, read incorrectly. It won't know if it's the sensor faulty or the signal the sensor is reading is faulty due to a physical fault. Hence why it defaults to F4 flashing and enters limp home mode because it sees an electrical problem. It's feasible to have cracks open up or seal when temperature rises. Others have had similar but few return with feedback after repair.

In a way you're lucky the auto can drive, be it only when warm. This proves it can work when it wants too which aids diagnostics. It's possible to measure the oil pressure via the points on the outside of the case using a pressure gauge. I would hope your garage either knows about auto's and typical faults on the Jatco. If not then it's a bit of a risk especially if the work done so far didn't solve the problem. It may be you have more than one fault which is why you still have issues after the solenoids where changed. This would be very unlucky. In the past peeps have paid around £600 for repair for replacing cracked pistons.

If you have lost faith in the garage you're using (I share the concerns of others raised above) then you would be betterer to look for an auto gearbox specialist in your area as opposed to a normal service/repair garage. The Jatco in the Freelander has been around since 2001 in Freelander's and is also used in many other cars in a slightly different format with different gear ratio's etc.
 
Thank you for all your comments. I have a new theory, They did not use the correct gearbox oil, as I have asked them if they used the correct oil, as I was sent this message.
Hi Julie,

Can you ask the garage exactly which gearbox oil they used. These gearboxes are very sensitive to the type of oil, they need a Texaco N402, there is no substitute. How did they check the oil level when they filled it? It must be checked by a diagnostic machine at 40 - 45 degrees celsius.


All the best,
Sue

They said that they used an alternative oil, which is just the same thickness. I traveled around several land rover garages yesterday and asked questions, one said it could be the oil as it is too thick when the car is cold, once the car warms up it thins the oil hence my car changes gear when the car is up to temperature. Can anyone comment on this please. I have tried to get it into one of these garages to have the oil changed again but no one can get me in till mid June make a comment about this please. I have lost faith in the garage that did the other work and do not want them to touch it again
 
I find it difficult to believe someone would know what the thickness of auto gear box oil is, and be able to compare it between brands. Especially when the manufacturers don't list the spec. A garage won't be able to compare this themselves by just looking at it.

How “runny “ oil is is normally measured by allowing it to flow through a small hole with gravity pulling on it only. The longer it takes the less runny the fluid. Auto oil is thinner than engine oil.

Changing the auto oil is something you can do at home as long as you follow the specific steps correctly. A standard fluid change doesn’t change all of the oil. It's only a partial change of about 42%. But you can then do it again after running the car for a bit.

The auto oil change needs to be done on level ground. Do you have a safe, level area where someone could change the auto oil at your house? Do you have someone who could do this for you if they follow the instructions on ere?
 
I find it difficult to believe someone would know what the thickness of auto gear box oil is, and be able to compare it between brands. Especially when the manufacturers don't list the spec. A garage won't be able to compare this themselves by just looking at it.

How “runny “ oil is is normally measured by allowing it to flow through a small hole with gravity pulling on it only. The longer it takes the less runny the fluid. Auto oil is thinner than engine oil.

Changing the auto oil is something you can do at home as long as you follow the specific steps correctly. A standard fluid change doesn’t change all of the oil. It's only a partial change of about 42%. But you can then do it again after running the car for a bit.

The auto oil change needs to be done on level ground. Do you have a safe, level area where someone could change the auto oil at your house? Do you have someone who could do this for you if they follow the instructions on ere?
I will check this out, thank you
 
Could it be the temp sensor? You could try putting what ever value resistor for full running temp is across the 2 pins on the jacto ecu when engine cold. Should fool jacto ecu into thinking box is up to temp...and see of ya gears work then from cold?

Temp sensor could be going oc when cold and then closed when warm/expanded.
 
Could it be the temp sensor? You could try putting what ever value resistor for full running temp is across the 2 pins on the jacto ecu when engine cold. Should fool jacto ecu into thinking box is up to temp...and see of ya gears work then from cold?

Temp sensor could be going oc when cold and then closed when warm/expanded.
The resistance test should display a faulty sensor. Can be done when cold or warm, with the engine oft. Temp sensor resistance varies with temp.
 
Found out that the wrong oil does cause the problem that I have, so flushing it out and then using the correct oil texaco N402 should work, I hope
 

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Can't see the pic on my phone but looks interesting. .I wonder if the different fluids affect the wiring/connections etc..as they seem to be swimming in the stuff..conductive fluid etc. Just a thought...build up of metal particles around connectors etc.
 
Unsuitable auto oil can cause all sorts of problems and sometimes a change works wonders but it seems strange the fault would only happen when changing from 3rd to 4th. Unless there's something specific about 4th like it being the first time solenoid B changes state, after first pulling away in first and changing up through all of the gears in sequence.
 

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