2001 Range Rover 4.6 Vogue Gearbox Fault please help

[eliot]

Really think the a/c drains are a red herring, but to prove - you can always disable the A/C by pressing the button (so the light comes on) - therefore no condensate draining.
You need someone with LR compatible diagnostics to pull the codes of the trans controller to see what its moaning about.

[djo2267]

Thanks for your input, yes probably take it for land rover specific diagnostics this weekend. I did notice that the clamps on the battery terminals was not really tight,i could move the clamp if pushed quite hard, so have tightened them. Need to take it for a drive and check it wasn't that. Could this cause the problem, or would they have to be really loose?

[djo2267]

update, took it to lr specific diagnostics and no gearbox fault codes logged. Drove home and when i turned the wipers on the gearbox fault come up again, the exact time i turned them on. Is it possible that my alternator has an intermittent fault when hot. The car is ok for first 15mins, so im thinking that when the alternator gets hot is when it fails? The only thing is, sometimes when i start from cold, the gearbox fault comes u[p straight away, when alternator is cold. Please can someone advise me on intermittent alternator fault and any tests i can do. thanks

[Impasse]

Your gearbox is goosed. Buy a new one. Everything else is a red herring.

[eliot]

Impasse said:

Your gearbox is goosed. Buy a new one. Everything else is a red herring.

Not sure if serious?

[Blaster72]

I'd be looking to have the battery tested or replaced to eliminate it. Weird electrical problems like this often stem from a failing battery and although a basic voltage test suggests it's ok it still could be the cause.

[djo2267]

Had battery and alternator tested 14.0v with all elecs on at 2000rpm, so ok. Battery is new. How do i test to see if the Gearbox ECU is working?

[Blaster72]

I think you really need to get it to a LR dealer and pay up for a proper diagnostic check.

As you have a fresh battery we can rule that out, have you checked the fluid levels?

As for the ECU check, the diagnostic will point you in the right direction. You could try a 2nd hand one but if a fault in the box has blown the ECU it could easily blow the new one.

[djo2267]

can low fluid levels bring up gearbox fault intermittently? When not in limp mode, it drives and changes through gears nice and smooth. Can a gearbox ecu be intermittent fault?

[Blaster72]

djo2267 said:

can low fluid levels bring up gearbox fault intermittently? When not in limp mode, it drives and changes through gears nice and smooth. Can a gearbox ecu be intermittent fault?

Low fluid levels - unlikely but its a basic check that should be done. It is possible the fluid is overheating if its really low.

ECU intermittent - can be definitely , could also be gearbox solenoids or wiring failing intermittently hence the need for the diagnostic check to narrow things down.

Edited by Blaster72 on Thursday 9th October 21:21

[With these feet]

Im certainly not LR expert, but if you are getting all sorts of electrical issues switching load on and off, I'd be checking all the earth terminals ie, battery, engine to body, gearbox, ecu etc. Some components will be earthed, possibly the ecu, directly to the body. If this has a bad connection it may give spurious faults. Just my 2p!

[djo2267]

took it to a land rover specialist with land rover specific tool t4 and no communication. I think there is power from the plug but no comms and they dont want to get involved with a p38, the same as 2 other specialists i have phoned. The fluid levels are ok. does anyone know how many sensors there are for the gearbox, what they are and whereabouts? Im driving around short journeys in and out of limp mode and its been over a month now. thanks