PRND works but the manual + and - doesn't?

Hi There

Just picked up a nice little low mileage 87K C3 year 2003 automatic 1.4 petrol for commuting in and out of London as driving my 3.7L Merc was getting expensive !

The car drives well in D, although I noticed that when sliding the gear lever over to the left to try out the manual up and down mode, nothing seems to happen and the letter 'D' remains on the dash, which I was expecting to show what gear I was in? Do I need to press the M or anything?

Also when I press the 'S' mode, the gears hold in the gear I am in and do not change up? is this normal? Similarly if I select the snowflake, id does not seem to change anything?

I plugged in my diagnostic and found no gearbox codes, apart from one old code - 'temporary Clutch Slip' however I cleared this and it stayed away.


All help and advise is appreciated.

UPDATE:

I have the PRND gearbox which works okay, but when I slide the gearshift over to the bottom left to go into the manual up and down selection nothing changes with the letter 'D' remaining on the dash, I was expecting this to show the gear number I was in? Reading this forum I suspect that the gear shift selector may be faulty so have a couple of questions:
1. Is the gearshift selector on the gear shift module and accessible to check and fix?
2. Should I just buy a new gear shift and is it plug and play or does it have to be coded to the car?
3. Is there a gearbox reset procedure and how?
P.S. One other point is about the 'S' button and 'Snow' button. When I press the 'S' button I can tell that the gears hold longer making it more nippy, but sometimes the revs need to go quite high before it changes up and sometimes with a thud, reading the forum this is probably a solenoid valve needing changing?
Lastly the woman I bought the car from only drove very short distances and did not even realise that you could use the manual gear shifts so could this be lack of use?
Thanks in advance.

If it is possible I would highly recommend changing the gearbox fluid. The specification is ESSO LT 71141. Apparently Mobil now make it. This may be responsible for some of the hard shifts. If overall, the gearbox shifts OK...change the fluid. Don't worry about the electro valves...just yet.

Citroen specify the gearbox is "sealed for life". THAT'S RUBBISH!!!!!! ANY fluid only has a finite lifespan. Engine oil and gearbox fluid are critical to the operation of the engine and gearbox and not changing them is a recipe for disaster! According to the engineers, theoretically, the gearbox fluid specified should last a very long time...IT DOESN'T!!! Most of the horror stories you might have read about the AL4 gearbox are mostly because the fluid is not changed on a regular basis. Clutch packs wear out and electrovalves get clogged because the fluid is not changed and get old.

If you can not find the specified fluid, a known brand, FULLY SYNTHETIC fluid will do. If you need more info for DIY just let us know.

The "snow mode" effectively locks the gearbox in 2nd gear and limits engine torque. It's for situations where the wheels might slip... like muddy or icey conditions.

'S' is for sports mode...to make the response a bit smarter. But you are right, it forces the engine to rev out too high. In 'standard' mode I find the gearbox is too conservative and in trying to save petrol makes the response "boggy" and lacks torque. I would have preferred if the 'S' mode was simply just less conservative and you didn't have to rev the t!ts off the engine to get it to change gear!

There is a circuit board and a magnet in the gear selector box that detect if you have selected 'manual' mode. I haven't seen this fault before but there are a couple of potential failure modes.
1) damaged or faulty circuit board.
2) missing magnet on the selector shaft.
3) an object stuck to the magnet, causing a failure.
4) the connector on the side if the selector box, connecting the circuit board to the gearbox ECU is loose or disconnected.

I will try in the next day or so to get some photos of the innards of the selector box to show you.

Meanwhile if you look in the "tips and tricks" area under automatic transmission, you might find some interesting reading.

I see the little elves have been to spruce up my post.

Ok, to get to the magnet and Printed Circuit Board(PCB) you will need to remove some panels.

If you look at this post it shows how to remove the panel in the center console.

Inspect the black electrical connector on the near side of the selector housing. Ensure the connectors are plugged in correctly.

Unclip and remove the blind guide and lighting/selector PCB. Next remove the 4 screws and the selector shaft guide. You can now see the back of the PCB and the magnet. Check the PCB for damage and see if the magnet is secure and there is nothing stuck to it.