I changed reverse light switch and it now works ok.but next day engine warning light came on and amber flashing info on ..in manual book it says transmission fault but rac scanned it and it said clutch control switch fault and brake pedal switch fault and glow plug fault.....I changed clutch pedal switch seems to have cleared that warning but engine warning still on saying glow plugs is it worth changing these or am I just waisting money as book says transmission fault......helpppppppp....any ideas or has anyone had similer problems any info much appreciated all the best.....rob

It cant hurt to change them fella, but before you do try erasing the error code and seeing if the engine light comes back on.

Sometimes the codes come up for a different reason to what you may necessarily think, it may not be the plugs themselves, it could be a loose connection or even a faulty sensor.

I dont know enough about diesels to give you a run-through but if the car's running mint I'd start by deleting the code and checking the connection's sound.