Drive in 2nd only!, no drive and slipping in P,R,N,D,1&3, AL4 Gearbox, no fault codes, no snow and sport lit?

[stevedh]

Hi, I am hopeful that someone can help me with this odd problem.

I have a 2006 Citroen C3 mk1 with an AL4 automatic gearbox (20TS19) and have a strange problem.

All was working fine, but then broke down with strange noises from the engine and no drive.

Once I got the car home, I scanned with transmission module and there are no fault codes, tests on all the electro valves seem to work just fine, I have oil pressure and the snow and sport symbols are not lit, so the TCM does not think there is anything wrong.

But the car has no drive in any gear except 2nd (when in manual selection).

In all other gearbox positions, P, N, R, D, 1 and 3, there is a scraping / rubbing noise from the gearbox, which I assume is either rubbing clutches or brake belts. But for some reason after a large clunk, gear 2 goes into drive with no scrapping / rubbing noises and wants to move the car.

A few months back I had harsh gear changes, so drained the box, replaced the two modulating valves at the top, refitted and refilled with fresh oil to the correct level (drained to a dripping when warmed up) and then the gearbox ran just fine again.

Since the break down I have now drained the oil, removed the valve block again and checked all looks good and the inner filter is not clogged and no signs of dirt etc. I have also swapped the positions of all the electro valves to see if this would change any behavior, but after reassembly and refilling the box with oil, there has been no change to the symptoms. I have also readjusted the multifunction switch as per the correct procedure and again no change.

I have also removed the pressure sensor and oil flow control valves and cleaned them to ensure there where no blockages with them.

I seem to be getting between 2.35 and 3 bar of oil pressure in any gear.

I am now at a loss as to what could be wrong, I assume it must still be something to do with the valve block, but have no idea what.

Does anyone have any ideas? Why is 2nd ok but the rest not, what could cause this?

Much appreciate any feedback.

[ozvtr]

Looks like a mechanical failure of one of the clutch packs.
From the AL4 manual, the clutch pack P1 or its actuator are the only components used in every gear except 2nd.

Edit: P1 is the planetary gear housing. The associated clutches are E1 and F1. If it's not the clutches then the planetary gear housing might be damaged.
My bet is the E1 clutch. Either way sounds like a mechanical failure.