Clutch not disengaging / releasing on C3 petrol 2002

My son was driving his car when without any warning he couldn't engage a gear while moving.
I took a look and notice that the pedal feel hasn't changed in any noticeable way. With the engine switched off its possible to engage a gear but with the clutch pedal depressed the clutch is still engaged.
My immediate thought was that the slave cylinder had failed so I replaced this as a quick and inexpensive item. All bleed with fresh fluid OK but still no joy with the clutch operating.
What is next on the list for me to try ?

Hello Splash-Man

Have your son depress the brake pedal and observe the clutch fork actually moves a good distance each time the pedal is pressed and released.

If the clutch fork moves the it's the clutch pressure plate next to look at/change the whole clutch.

If the clutch fork doesn't move / move enough then you should be looking at the clutch Master cylinder (because it's not the slave as you have already changed that)

Cheers for that. I'm pretty sure that I remember a reasonable amount of movement on the slave cylinder / fork arrangement.
I'll take a closer look to see what is actually moving.

The slave cylinder acting on the clutch fork as the clutch pedal is operated.

Splash-Man wrote: ↑Wed Dec 12, 2018 2:21 pm I'm pretty sure that I remember a reasonable amount of movement on the slave cylinder / fork arrangement.

If this is the case, then the clutch pressure plate or release bearing/release bearing guide has failed, but whichever it is, a complete clutch kit (check here at ECU) would be prudent while the bell housing is off.

It is not a cheap job.