Hi XXXXXXXXX.
Thank you for your question.
EP stands for "emergency program". When the engine management system detects a fault it places the car into this mode to prevent damage to the engine or gearbox. You will have to take your car to a garage for a diagnostic check to be carried out. This check will interrogate the ECU and give a fault code which will point you to the cause of the problem. Most good garages are able to carry out this check these days, so phone around a few for quotes. Locally, (to me) they charge between £40 and £60. Once the fault has been repaired, the fault code can be cleared.
As for the temp gauge, check the water level, if it's low, then check for a leak. If not, it's most likely the temperature sensor which is screwed into the cylinder head. I would get this tested at the same time as the diagnostic check is done, before attempting to remove it.
I hope this answers your question.
Regards, XXXX.
UK Car Mechanic
Mechanic and MOT tester for 18 years. Excellent knowledge of cars and the MOT testing scheme.