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Rover 75 CDT Auto - Gearbox problem

29K views 20 replies 7 participants last post by  neil waring 
#1 ·
Urgent help and advice needed! My gearbox selector seems to have given up the ghost. On start up there is no display of P, R, N or D. I managed to drive the car home by selecting 3 but needed to be pushed backwards into my drive. I have a feeling this could be a bit costly.
Any ideas as to cause of this problem or of how to sort it.
 
#2 ·
Dont't despair. It may not be that bad. Unless there has been some advanced warning that things were going wrong, it is unlikely it is a purely mechanical problem.
There are several possibilities

Oil level

There is a cable link from the gear selector to the gearbox- may be disturbed.

The inhibitor switch on top of the gearbox, which tells the ECU what gear has been selcted. This is a muliti position switch, with contacts which may be dirty or broken. This is also fed from a fuse which may have gone.

The ECU in the front passenger footwell, maye be dead. Easy to replace, but possibly expensive.

There are numerous sensors, both outside and inside the gearbox itself, any of which can cause the ECU to malfunction.

As I understand it, the ECU will default to a "get you home gear" of 4th.

All faults are logged in the ECU, so a proper garage can download the fault codes and find what has gone wrong.

May not be as bad as you think

Good luck
 
#4 ·
Bob,
Just another thought, which may just work.

Try dissconnecting the battery for about 30 mins. Sometimes this works to cure engine ECU problems, so may "re-boot" the gearbox ECU as well.

Make sure you have your radio code before you do it.

It's certainly worth a try. After all, you have nothing to lose & everything to gain.

Let us know if it works.

Good luck & a Happy New Year

Colin
 
#5 ·
Hi Colin,

I decided to put your battery theory to the test this morning but found, to my amazement, that all functions had returned to normal and I was able to drive the car as normal. I suspect however that the extremely wet conditions I had been driving in had, in some way, affected one (or some) of the gearbox sensors and/or connections.
I have today put the car in to the local (ex) Rover dealer for a service (due in a couple of weeks) and to have the gearbox checked out just to be on the safe side.
Your suspicions that it was'nt mechanical appear to be absolutely correct. I'll let you know what the garages verdict is when I pick the car up - hopefully tomorrow.
Many thanks for your help.
Regards,
Bob Sharpe
 
#6 ·
Hi Colin,

I decided to put your battery theory to the test this morning but found, to my amazement, that all functions had returned to normal and I was able to drive the car as normal. I suspect however that the extremely wet conditions I had been driving in had, in some way, affected one (or some) of the gearbox sensors and/or connections.
I have today put the car in to the local (ex) Rover dealer for a service (due in a couple of weeks) and to have the gearbox checked out just to be on the safe side.
Your suspicions that it was'nt mechanical appear to be absolutely correct. I'll let you know what the garages verdict is when I pick the car up - hopefully tomorrow.
Many thanks for your help.
Regards,
Bob Sharpe
Bob,
Great news. At least 2007, seems to have started a little better.
Just one thing though. I think it is worth you checking for water ingress in the region of the fuses in the passenger footwell area, Just in case that water has got at the gearbox ECU. Also there is an oft quoted problem on here about the engine ECU, which is housed underneath the bonnet in the infamous 'plenum', which can have blocked drains and thus a drowned ECU. Do a search & you'll find lots of entries.

Cheers

Colin
 
#7 ·
I had the same fault a couple of days ago, put it to the local ex-Rover agent this morning, and the dignostic check revealed a blown fuse. They changed it (Didn't say which one) and cleaned some plug terminals, and it is OK. £57. I would like to know, however, how do you access the gearbox computer in the pax footwell, and do any of the advertised diagnostic gizmos work? Mine is a 2001 diesel auto, so I would like a gizmo that can interogate the box.
 
#8 ·
Jim,
As far as I know, access to the gearbox ECU is via the main diagostic bus, which looks at all the ECU's. For this, the special T4 software is required, which only ex-Rover dealers have and one or two individuals.
There is a thread higher up about re-mapping the gearbox, which may be of interest to you.

Colin
 
#9 ·
Hi there! First-time poster so be gentle ;)

I have Rover 75 Tourer CDT; 2002 with the BMW Autobox. Only done 52k miles. When changing up from 3rd to 4th it does go into gear but then drops out of gear, increases RPM then goes back into 4th gear. Weird huh! :err: It happens every time. ie it's not an intermittent thing.

It has just had a service and CPU check and reset but this has not helped. The service agent did confirm that the CPU was okay.

If anyone has any ideas, or needs more info, please let me know.

All (helpful) comments appreciated :D
 
#10 ·
Hello Neil.

In fact it's a Jatco autobox, not BMW (who don't make their own but tend to use ZF).

I've some working knowledge of older autoboxes but not modern ones. However I have come across the sort of fault you describe under two situations:
1. Low fluid level (needs checking when hot and with engine running).
2. Car has been standing unused for a while, such as on a dealer's forecourt, and the valves get a bit sticky. Likely to be cured by some hard driving, up and down the box with good use of kickdown.

I doubt if these will answer your problem but may be worth bearing in mind as possibilities.

David.
 
#11 ·
Hi David,

Thank a lot for your quick reply and I am very impressed :) I think you may have got it right on either of your answers.
1. ( Fluid Level ) The fault when cold does not seem quite as bad i.e first few miles. Only done 8000 miles in it myself and do not know the history ( if it has been checked ) though I bought it at a reputable garage and was serviced at the time.
2. ( Valves ) The car has been used intermitently and I have only used it locally plus I am a steady driver which may or may not help. I know nothing about valve either, is there one for each gear ?

I will try your sugestions and post results when I have them, thanks again.

Neil
 
#12 ·
Neil,

It's not unknown for even experienced dealers to check the fluid level without the engine running. My local Mercedes main dealer did that in the 1990s on an E-series, and the main Ford dealer likewise 10/15 years earlier on a Capri. In both cases this led to slippage and the car owners were told that a new gearbox was needed. Checking the level with warm transmission and engine running showed that all that was needed was a bit more fluid!

I don't know what valves are in the Jatco box but autoboxes contain various valves, solenoids, clutches and brake bands, a fault in any of which may lead to slippage. However the fluid level is always the first thing to check (at least this was the case before ECU controlled boxes came along).

Earlier autoboxes were less stressed and tended to contain more fluid, so changing the fluid wasn't normally a service requirement. I believe the Jatco box does require periodic fluid changes so perhaps it would be worth getting this done and hoping that the new fluid, and the correct amount of it, will cure the fault. Now you've explained the recent history of the car, I think there's a very good chance it will.

David.
 
#13 ·
Hello David,

Interesting anecdotes which usually cost money, especially on cars.

I am lucky in that I have a guy locally who has a fair amount of experience on Mercs and Rovers along with the necessary computer equipment to do all the normal checks and resets, though admits that he has not done much work on automatic boxes and will have to ask questions of other people who have,which is fair enough in that he is not trying to con me, and this being the reason for this contact with people like yourself, you can't beat actual experience !

Just another thought regarding the Rover, is the engine a BMW product as I thought, because I have not heard of the jatco gearbox before now, though I have been abroad for some years.

Regards,
Neil
 
#14 ·
Yes, the engine in our cars is the BMW, similar to the one used in the 320 for example, but with less power and a few other differences. The one in the 320 is type M47 whereas ours is the M47R (R for Rover).

I think Jatco has been in business for quite a while but probably not commonly used in Europe. I'm more familiar with Borg Warner and GM from several decades ago, having worked on them as an amateur. The box I mentioned as having drive slippage through standing unused was an ECU-controlled 5-speed ZF with lock-up and I wouldn't want to try rebuilding one of those!

David.
 
#15 ·
I am pleased to know that the engine is in fact a BMW and happy with the rest of the car and it performs reasonably well for a car with a lot of weight. Like yourself although I have stripped down and rebuilt both bodies and engins for quite a number of years but those day's are gone for me now especially with electronics involved.

Have taken the car in today to have the gearbox oil changed and the drain hole checked where the CPU is housed under the windscreen, so hopefully it will solve the gear change problem and save any future water ingress problems, will let you know.

Neil
 
#16 ·
V.I.P. In this case this means VERY IMPORTANT POSTING.
Read posting 18/03/2007 for fault on gearbox.

well I'm not a happy bunny today , guess who needs a new gearbox ?
anybody got one lying aroung in a plastic wrapper and wondering what to do with it !

Cause of the problem is a cracked "Talk Converter" this does not allow the pressure to build and change gear initially between third and fouth. Unfortunately there is no indication either electronicaly or otherwise that this is going on or about to give problems but when it does, it is already too late the damage has been done to the friction material etc. There are other people on this site I am sure who will better able to explain it than me as this is just the basis of what the news I have just been given today.
Apparently it is a known problem by Jatco and the box has been modified to cure it after which it gives no more problems.

If it wern't so cold out I might try selling my body on the streets to raise a bit of cash, trouble is I might have difficulty raising anythig else :shh:

Now the price, somewhere in excess of £2000.00. Please look out for my charity web site which will be set up shortly. :)

Neil.
 
#17 ·
That's very bad news, Neil. A search has brought up other postings on the problem - see http://forums.mg-rover.org/showthread.php?t=157976

My 1972 Triumph 2500 went 207,000 miles with the original Borg Warner 35 auto gearbox, including the original torque converter, with never a change of fluid. It was getting a bit sloppy by then (1998) and I changed it to manual + overdrive. Even when they did go wrong, they were fairly straightforward to work on.

Seems we have gone backwards in some respects. Some not-so-old Ford autoboxes are terrible in refinement and reliability terms and now it seems that Jatco (owned I think by Nissan) is also a bit 'iffy'.

I hope you find a less costly answer - it may be useful to speak to some auto box specialists.
 
#19 ·
Neil,
Sorry to hear that, but I am very suspicious of that diagnosis. If the torque converter was cracked then you would be getting higher engine revs most of the time ( ie it is slipping more than normal), but it would change gear. Gear changes are effected by a separate hydraulic pump, which is controlled by solenoid valves, which in turn are controlled by the ECU. If the hydraulic pump was knackered then yes that would cause major problems. Also a misbehaving ECU could cause similar problems. There is clearly a pressure problem, which the ECU is trying to overcome, or a pressure sensor is wrong, which affects how the ECU behaves.

By they way, you have not said how many miles the car has done? If it has done a lot, with no oil change, then yes, things could go wrong.

I personally would get a second opinion, preferably from an EX Rover service centre, and put it on the "T4" diagnostic set.

Colin
 
#20 ·
Jatco Box

Hi Neil. Sorry about your problem and can't help much with repair info. I'm afraid.
As for Jatco boxes I had no knowledge at all of these when I bought my auto CDTi. I do understand however that Jatco are, in fact, one of the largest manuf. of auto boxes. Land Rover also use them (think Jaguar have also) and a number of Japanese vehicles, which on the whole, have a good reputation for reliability. There have not been many out and out failures in our cars and in most cases it appears to be linkage or incorrect or ovedue fluid changes that seem to be most common. Recommended interval is 60,000 miles or 4 years and MANY of our cars have reached 4 years even if not 60,000 miles.
Many of us have decided to change fluid at 30,000 and members having improved changes etc. and preserving the box could indicate this is worthwhile.
However WARNING ! many members having had the fluid changed do not know if the correct fluid has been used. Garages are frequently telling members "we use Castrol, they are all the same". Our one member on hearing this phoned 10 'Rover w/shops, not one of which could tell him which was the correct fluid for the Jatco box.
The one and ONLY fluid for the Jatco box is Texaco N402/ATF402. Part No. VYK00040 from Xpart or LNR402 from Land Rover. Xpart price is £20.70 / 5 Litre (+VAT) and the change will require about 4.5 litres. It is impossible to drain all 6-6.5 litres.

Ashcroft transmissions do an exchange box (supply only) for £850 exchange. (Tel.No. 01582 496040. Luton Beds.)

TES Transmission Ltd. also sound knowledgeable on Jatco. (Tel No. 01373 822041 - Westbury, Wiltshire)
Please let us know how you get on. Good luck
 
#21 ·
Hi Dizzy, David, Colin, & Crofts,

Advise and coments much appreciated.

I have decided not to rush into the repair to give me time to check out the the garage report.

I am also hopefull I can find a less expensive repair option with the combined knowledge help of you guys out there.

I will follow up all the leads you have given me and be in touch.

Thanks again,
Neil
 
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