With the engine not running and ignition switched on, foot on brake, the display panel shows I can select 1st, reverse and neutral fine. When I start the engine the display panel shows, gear unavailable, the vehicle behaves as though it is in neutral and will not move. Anyone any ideas?

Bump.

Bump.

Are these a robotised single-clutch manual? - like the Alfa / Fiat Selespeed?

If so, sometimes an ECU reset will cure problems - perhaps caused by a sensor sending a dodgy signal.

Also check the hydraulic fluid level in the reservoir, as this can cause selection issues.

After that, you're down to looking at the accumulator and actuators.

Used to be really expensive and a full swap-out, but there are now specialists who can refurbish and replace individual parts.

Autotrail1 said:

With the engine not running and ignition switched on, foot on brake, the display panel shows I can select 1st, reverse and neutral fine. When I start the engine the display panel shows, gear unavailable, the vehicle behaves as though it is in neutral and will not move. Anyone any ideas?

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I dont know if you have solved your problem but I had the same thing happen to my comfortmatic gearbox.
It turned out to be the dual mass flywheel and clutch on mine.I have a 3litre engine on a tag axle 5 ton motorhome,which had only just done 40,000 miles.
John

Does the engine rev when foot put on accelerator? If not, good chance the throttle sensor has glitched. This will cause the malfunctions you refer to. Needs a scan to cancel out and see if it returns again.

Could someone please tell me how to locate the special fuse box for the comfortmatic and if possible a diagram. I have looked at the three fuse panels and I understand that the comfortmatic has an additional one for f26 and f27. Any assistance appreciated.

Hope you have sorted this problem, If not, it has two hydraulic systems, one for the power shift and the other for the clutch. When the engine is running the power shift hydraulics controls the clutch actuator which in turn moves the clutch hydraulics, it has a position sensor in the clutch actuator and senses the position of the clutch. This separates the drive and allows the gearbox to slow down or stop allowing gear selection. (in essence, imagine you were driving a manual with a clutch pedal, you can't select gears without first dipping the pedal) I think your problem will be with the clutch or the hydraulics, You could try and vacuum the DOT 4 fluid through the bleed nipple which is located on top of the gearbox. If the fluid is black the slave has probably failed. Usually bleeding the clutch hydraulics is done using the diagnostics but can ve vacuumed. Open the bleed nipple by twisting it one way or the other. Mechanically the clutch disc maybe stuck or seized on the splined shaft preventing the gearbox from slowing down during gear selection. You said that when the engine is off and Ignition on that you can select N,R & 1st This tells me that the power shift hydraulics are ok and looking for the fuses wont fix your problem. be aware that Powershift fluid is different than the clutch fluid. good luck