1998 xantia 1.9 TD auto gear box no forward gears?

[Rotary-Motion]

hello all

this is my first post and i was hioping that you may help me on an issue with a xantia automatic gearbox, i can only select reverse gear, i have no forward gears?

anyone come across this problem before?

thank you in advance...

[CitroJim]

Hi and welcome to the forum

A 1998 1.9TD I would think will be fitted with the Siemens AL4 autobox.

Strange it'll only select reverse as the same clutch is used for both first and reverse although different brakes are used.

Is there no drive at all going forward or is the engine straining against the torque convertor in forward gears suggesting the 'box might be locked up?

What (if any) symptoms did it show before failure? Any strange noises or behaviour such as jerky changes?

My first thoughts are the selector cable and the gear position switch. Check the cable is properly operating the selector lever on the gearbox.

Any problem with the selector switch should cause the 'box to fall into hydraulic emergency mode whereby reverse will be available and third only availabe in D. The emergency mode will be signified by the sport and snow lamps flashing.

Really, to fully determine what is wrong requires a diagnostic session from a Lexia Diagnostic System.

If you disconnect the gearbox ECU (under the battery) the 'box should revert to hydraulic emergency mode by default. It'll be a good test to see if forward motion is possible then, albeit in third gear only. If so, the problem is electronic. Be sure to disconnect the battery before disconnecting/reconnecting the ECU.

[CitroJim]

Looking further into this, the symptoms could be caused by a problem in the valve block (either a failed electrovalve or mechanical) or a failed brake.

It'll be well worth checking the oil level and condition as this is critical in these boxes. The oil should be golden (maybe quite dark, tending to black) and have a distinctive smell not unlike strong cats pee. If it smells really burned then a clutch or brake has failed.

Also beware if a well intentioned oil change has been carried out in the past using the standard red Dexron fluid. You can tell this if the oil is tinged with pink or red. If so then the box will have suffered serious damage as a result as the only oil to use in these is the Esso LT71141 and Dexron is far from suitable.

Oil level is critical and needs to be checked according to this instruction, noting the requirement for the 'box to be at a certain temperature.

[Rotary-Motion]

thank you very much for all the infomation you posted...

no it just happended all of a sudden, does not even try to move in forward gears, was originally pulling up hill at about 50mph and suddenly stopped driving, no snow lamp on?

perhaps its a dead box?

paul

[CitroJim]

perhaps its a dead box?

Hi Paul,

It's looking likely but before making that conclusion, force the 'box into emergency mode by disconnecting the ECU. If you still have no forwad motion then, suspect something has let go inside.

Then do the oil level/quality checks outlined above.

Loss of first gear whilst still having reverse points to the brake band F3 not engaging. This brake is used only in first and second gears. Dropping the 'box into emergency mode will make it go directly to third where only clutches E1 and E2 are used. By the fact it goes in reverse you know at least E1 is working.

If it is proved that F3 is not engaging, this could be electronic or a mechanical problem with the valve block. It's not unknown in the similar ZF gearboxes for the slide valve loading springs and retainers to break after a high mileage. If this happened to the slide valve(s) that control brake F3, then that will give the symptom. The F3 brake band could just be worn out or more likely burned out, especially if there was a developing valve block problem that reduced operating pressure to its servo.

At high mileages, it's not unknown for the oil filter to block and reduce oil pressure considerably. That may be a contributary factor. As these 'boxes are so-called "sealed for life" the oil filter can only be replaced after a full disassembly of the 'box.

I've not had an AL4 in bits bit they're similar to the 4HP20 used in the V6 and they are quite amenable to repair although spares are a touch on the pricey side. I would imagine the AL4 is similarly amenable to repair.

As I say, check the oil and drop it into emergency mode by disconnecting the ECU (after disconnecting the battery!) and report back with findings...

[Sid_the_Squid]

As the PDF linked by Jim suggests you will need some oil in order to effectively check the oil level.
As already mentioned the only oil suitable is Esso LT71141. You can obtain this from any Citroen Parts dept, the item number is; 9736.22, give this to the parts guy he will relive you of about £17 for a 2 liter bottle.

Check for any duff fuses both inside the car and under the bonnet. I don't know if a duff fuse could cause this issue but its always worth checking.

I am surprised to hear that you do not see the sport & snow lights flashing simultaneously. Do you clearly see the appropriate led light up by 'D' on the dashboard gear indicator. it should light up solidly, not flashing. Flashing lights on the gearbox dashboard indicator are always bad.

Please check this thread out for more information on how to check the oil in an AL4 box. http://www.frenchcarforum.co.uk/forum/v ... hp?t=27378 Its a long thread but I do suggest you read it all.

[jag555]

hi!
old tread but i have the same issue, xantia 2.0 automatic, -98. only revers, nothing forward, no fault lights, correct oil level, 13000km, cant find ECU under battery, can it be located somewhere else? just bring the car home and know no historic!
so i wanna ask what was faulty in auto? and where i can find ECU for my automatic, nothing under battery is seeable to put the automatic to hydraulic mode? maybe pull off a fuse?
thanks