Freelander 1 Jatco auto gearbox problem

[bukko]

Personally my gut feeling - not based on anything real though - is that there must be a design reason for the exaggerated jerk from 2-3 and 3-2 if there is a gearbox problem.
I guess for some reason those transitions are more vulnerable to problems.

My gearbox is great now, but even now when cold there is still a slight delay when changing from 2-3.
When it was bad, 3-2 was always the worst change by far, 2-3 almost as bad.

Interesting about the air-con though. Does having the air-con running introduce more inertia to the engine side of the gearbox? Maybe that's why, I dunno.

 

[ianda12]

Hi Hippo
Update on my gearbox that has intermittent harsh gear changes, especially 2-3 and 3-2.
Changed the 2/4 brake duty solenoid and the Line pressure solenoid.
Gear changes now even worse than before.
After reading some threads on the M.G. forum, I removed fuse F4 for 10 mins. to reset the T.C.M. (with ignition turned on), then tried it. Is now changing O.K.. As the fault is intermittent I think it is coincidence and will play up again in the next few days.

 

[Hippo]

Hi Hippo
Update on my gearbox that has intermittent harsh gear changes, especially 2-3 and 3-2.
Changed the 2/4 brake duty solenoid and the Line pressure solenoid.
Gear changes now even worse than before.
After reading some threads on the M.G. forum, I removed fuse F4 for 10 mins. to reset the T.C.M. (with ignition turned on), then tried it. Is now changing O.K.. As the fault is intermittent I think it is coincidence and will play up again in the next few days.

Monitor it for a bit and see how it goes. My problem is still there but less common now. I still think it's electrical. Thing is I have to wait longer to see if on average the fault happens less often. Hence taking a while to solve. A number of times recently it's had some good spells to the extent I thought it felt like new. Gear change perfect and betterer than when I thought it was good. Then occasionally the fault comes back. Keep at it and hopefully you'll find the fix. Sad news on the solenoids.

 

[Nodge68]

When mine is cold, I get the odd thump both up and down. The computer can't compensate for all driving conditions in the same way that you can with a manual box/ clutch.
I find the auto box rather dim witted unless it's in sport mode, then it's just about acceptable.

 

[ianda12]

Hi Hippo
What was wrong with your spare box ? Is it the same symptoms as we are having now ?
Thanks

 

[Hippo]

When mine is cold, I get the odd thump both up and down. The computer can't compensate for all driving conditions in the same way that you can with a manual box/ clutch.
I find the auto box rather dim witted unless it's in sport mode, then it's just about acceptable.

I've driven many auto's as hire cars. The best for smoothness and usability was an N plate Nissan primera. The FL1 comes close but the FL2 is much betterer. The D4 auto is the way forward in terms of number of gears and the ability to stay in gear when both turbo's are running, on kick down in 4th at 30mph. Ours would drop to 2nd. If you think about the FL1 sport thing... the revs are likely to be higher in sport mode. Compare this to a manual in 3rd changing up to 4th at 3500 revs. If you change from 3rd to 5th you feel an odd change of speed due to incorrect gearing/speed but no where near as odd as you would 2 to 4 instead of 2 to 3, all at lower revs of say 1500. Hence I don't think the odd timing mistake will show up so much when at higher revs. Hence your feeling over sport mode being smoother. The auto is very clever. Probably more so than the engine. Not as clever as the newer ones out today, but for it's age the FL1 auto had some clear tricks. Bit like the FL1 in general.

Hi Hippo
What was wrong with your spare box ? Is it the same symptoms as we are having now ?
Thanks

The spare came from ebay and I was told the only thing wrong was 1 sensor reading incorrect resistance. It was never fitted to ma hippo. The torque converter is missing but who needs one of them. I knew it was missing but bought it anyway as I wanted to take it apart to see what's inside and have a practice at taking it apart just in case mine needs repaired again. I have some more video to upload of it when it's edited. Also more to film. The v6 it came from was being sold in bits. Torque converter was weighed in with the engine. I was going to chuck it after taking it apart but now I want to keep all of it just in case.

 

[LanderFree]

I Replaced my fluid aprox 10k miles ago and it was good. Started doin that good stuff 5k miles later. Sometimes ill drive at a constant speed or accelerating and ill get a kick like the trans locks then releases. Rare but it happens. Ill just keep changing fluid and lookin for particles in old fluid. Anyone use less expensive oil in the Jatco (ex: mercon dextron).

Did you notice any differences

 

[Hippo]

Changing the fluid on mine does make a difference. I only use LRN402 from main dealers which can be controversial on ere as other makes quote they're fluid is suitable. I don't care as I have a bill for the recon replacement on mine and an oil change is less than 3% of the recon bill.

There's a set way of changing the fluid which I've posted up on ere. A fluid change works wonders on the Jatco. Often miracles happen and solve strange faults. If you do it wrong you may fek yer auto.

As for my problems... my auto is working betterer than it has done for many miles. That may have feked things up as I'm certain ma hippo reads the forum looking for his next fault. This weekend will involve some time trying to work out why it's betterer and if it's linked to what I did to it recently..

This is the method to change the auto oil in the Freelander 1:

https://www.landyzone.co.uk/land-rover/jatco-automatic-gearbox.69336/page-3#post-1055940

Bank holiday weekend this weekend.

 

[Hippo]

Quick recap:

2001 v6 Freelander 1 has a bump on down change from 3 to 2 when slowing down. Fault is intermittent. If I put the air con on the fault is far more likely to happen. Mad I know.

Update:

Since last posting on ere me down change from 3 ro 2 (I think) has got betterer. The fault rarely happens now. Even when putting the air con on it doesn't bump as often as before on down change from 3 to 2. The fault is still intermittent and will happen with the air con oft, but is far more likely to happen with the air con on. So somehow I've managed to reduce the frequency of the fault or it's happening less often by luck.

I've been monitoring the voltage on fuse F4 in the engine bay fuse box which powers loads of things like the air con, electric fans, engine sensors, auto's computer/solenoids/sensors etc. Meter isn't really fast enough to catch a blip but I still kept the meter on constant when driving to see what it said the voltage was when the fault occurred. I also swopped the main relay in the engine bay fuse box (relay R4) for the sunroof relay under the steering wheel in the driver fuse box (relay R4 too) as my sun roof fuse has been taken out so the sunroof relay int done much work during it's life. For those that don't know, removing the sunroof fuse is the bestist sunroof fix available. Contacts should be betterer on the sunroof relay compared to the main relay as it's less used so hopefully less worn. Sadley this didn't provide any noticeable improvement in the down change fault. I did drive for a while before the next stage.

For a while I've been looking for what I think is an intermittent electrical fault. Loose connection or worn relay contact. Might even be a connector which int gripping terminals tight enough. I've sort of convinced myself it int the auto mechanically as putting the air con on dramatically increases the chance the fault will happen on the next down change. All the effected parts are supplied from the same relay/fuses. Hence the power supply is sort of common to all.

I then took the engine bay fuse box apart. Loads of pic's on the fred below about this. When it was apart I squeezed all the little metal clips together in the hope they would connect betterer to the pins on the engine bay fuse box, the push in fuses and relays. Made sure everything was clean and there's no rust in there. Fuse box has been put back a while now and auto down change from 3 to 2 seems to be betterer now. It didn't suddenly become betterer as soon as the fuse box was put back together. So I can't link it directly to the fuse box opening/squeezing/re-fitting but can't see anything else I may have altered which reduced the frequency of the problem. I did remove the connectors from the rear of the engine bay fuse box but they seemed ok at the time. No rust. So it could be down to luck or the fault has decided to hide for a bit.

http://www.landyzone.co.uk/lz/f9/engine-bay-fuse-box-254159.html

P8171568 yn4O1o4

DSCN4051 CrS1de9

This is one of the clips I squeezed together:

DSCN4077 QgVfaiB

It's good news that the fault happens less often, even with the air con on, but a little annoying it hasn't cleared completely. As it's imtermittent it's difficult to capture.

My next plan is to look at more items powered by relay R4 in the engine bay fuse box. This includes the VIS motors. See this fred:

http://www.landyzone.co.uk/lz/f9/disconnecting-vis-v6-258189.html

I get an error P1475 "variable intake balance value short to ground" occasionally. If I delete the error code with me hawkeye it comes back after a bit.

Since the fault has reduced the engine feels more smoother and so does all the gear changes, and not just the fault down change being smoother. It's as if I can now communicate with ma hippo and sense his feelings, to know if he's feeling unwell or not. On trips when he's feeling betterer I put the air con on and the fault doesn't happen. On bad days I sense it's a bad day and it is - occasional bad down change even with the air con oft. Sometimes a few in a row.

The other gear changes were acceptable before. It was just the 3 to 2 down change I didn't like. It seems to give a feeling of more power or smoother power delivery on good trips. It may not be, but it got me thinking. I wonder if there's an intermittent short to ground on the VIS causing my intermittent auto problem. VIS is powered by the same relay as the auto's computers and sensors, the air con and fans and engine sensors. So I'm going to look into that next. Also I may have a play with me hawkeye to see if I can manually put the air con fans on without the air con, to try to create a poor down change when slowing down, but without the air con itself running. I'm hoping this is possible and it won't get blow'd up.

 

[Nodge68]

Is it not possible that the AC compressor clutch is engaging randomly at the exact moment the box does its down change. This would slow the engine slightly due to the increased load. The engine ECU won't know the AC compressor has engaged for a few milliseconds so can't compensate immediately, hence the rough change.
Just another angle for you

 

[Hippo]

Is it not possible that the AC compressor clutch is engaging randomly at the exact moment the box does its down change. This would slow the engine slightly due to the increased load. The engine ECU won't know the AC compressor has engaged for a few milliseconds so can't compensate immediately, hence the rough change.
Just another angle for you

Good idea. I was wondering if the fans were causing the problem. Previously I tried to get the plastic lid oft the controller mounted on the fans to see what's inside (problem connections etc) but struggled and gave up. I will have another go at this. I think I will also put a wire to the output of the air con relay to see when it's supplying power to the air con clutch. If the LED on the wire goes out when it should be on, then this will give me a further clue. will also check the electrical connections on the air con compressor. I've just looked again at the air con in rave and it says it can switch oft if the pressure is high or one of it's sensors screams. Thanks.

 

[Nodge68]

To test the AC compressor theory. You simply need to connect an LED (faster acting than a bulb) to the compressor feed wire. This would give you an instant signal that the AC compressor had kicked in. The compressor switchs on and off because the tri mode switch tells it to. The mid pressure causes the compressor to run. This increases the pressure of the gas until the high pressure switch shuts it off again. The low pressure switch cuts the AC compressor out completely to prevent it running with low gas pressure.
Don't bother with the fan control unit. It's a solid state unit that is pretty boring to look at. I have changed a couple of power transistors in mine as a precaution.

 

[Hippo]

I've just been looking at rave again regarding the air con. Lots of sensors to go wrong so I think this will be next on the list to check. With the fault being intermittent I'll stick a led on it and see what happens. It would be strange if the air compressor was creating a dip or spike. Well worth a try.

 

[GrumpyGel]

You say the problem is when the box is gong down from 3 to 2 - is this because the car is slowing or is it kick-down to increase speed?

If its when slowing down, do the problems occur when you still have some throttle on or when your foot's off the accelerator completely? If it its when your foot is off the accelerator could the problem be related to engine idle speed? This is affected by having the air con on, so if your idle isn't too flash when the aircon is on, maybe its confusing the box's ecu? Might be something completely unrelated to the box - eg air flow sensor.

I should qualify these thoughts by adding that I haven't got a clue what I'm talking about!

 

[Nodge68]

You say the problem is when the box is gong down from 3 to 2 - is this because the car is slowing or is it kick-down to increase speed?

If its when slowing down, do the problems occur when you still have some throttle on or when your foot's off the accelerator completely? If it its when your foot is off the accelerator could the problem be related to engine idle speed? This is affected by having the air con on, so if your idle isn't too flash when the aircon is on, maybe its confusing the box's ecu? Might be something completely unrelated to the box - eg air flow sensor.

I should qualify these thoughts by adding that I haven't got a clue what I'm talking about!

I suspect it's something to do with light throttle and varied loads on the engine. Mine has a slightly thumpy change when cold while going down hill.
The UK spec V6 doesn't have an air flow sensor, it uses a map sensor instead

 

[Epicuser]

I have a jerk on my auto going from 4th to 3rd. It only happens when I use engine braking to slow down, so have foot slightly on the gas. It gets down to about 1100rpm then jerk changes down to 3rd. Happens every time under these circumstances, and seeing as I drive in 30mph limits too much of the time, it happens lots.

It doesn't do it when I take foot off gas and brake. Certainly nowhere near as noticeable.

 

[Tempus Fugit]

Hi Hippo
Update on my gearbox that has intermittent harsh gear changes, especially 2-3 and 3-2.
Changed the 2/4 brake duty solenoid and the Line pressure solenoid.
Gear changes now even worse than before.
After reading some threads on the M.G. forum, I removed fuse F4 for 10 mins. to reset the T.C.M. (with ignition turned on), then tried it. Is now changing O.K.. As the fault is intermittent I think it is coincidence and will play up again in the next few days.

Had similar on mine, have had fluid changed as well as solenoids, made some difference but still suffered with a harsh change. Pulled F4 and reset and now the changes are seamless, probably only covered around 200 miles but still good.

Thanks for this excellent piece of advice, just imagine going to a garage and being advised that the only solution was a recon box.

Now on to cure the slight coolant leak.

Thanks again.

 

[Hippo]

Is that fuse F4 under the bonnet?

 

[Tempus Fugit]

Is that fuse F4 under the bonnet?

It is.

TF

 

[Hippo]

Removing fuse 4 would remove power from the auto's computer but I don't see how this would make a difference?

The Main relay RL4 in the engine bay feeds power to the auto's computer via fuse 4 when RL4 is on. RL4 is only on when the engine computer requests, when the ignition is on. When the ignition is switched oft RL4 stays on for something like 3 minutes (I was playing with it recently on mine but can't remember exact time) then switches oft, and the engine computer remains powered. Rave confirms this and says it allows time for error codes to be stored in the eeprom. but that's sort of thing is done within a blink.

As the engine computer is permanently powered by a different fuse, I don't see what removing fuse 4 would do that's different, other than the engine being in "ignition on" mode as opposed to "ignition oft" or "sleep" or "alarm on" mode, if these conditions exist. Removing fuse 4 and therefore killing power to the auto's computer is what the engine computer does anyway, when shutting things down after the ignition is oft.