Hyundai Repair: engine light, transmission control module, engine control module ecm

Question
i am having a problem with the engine management light. i took it to a garage who charged me a bomb and said the fault was due to fuel pump or its relay. after diagnostics he found it was due to the relay and replaced it but after 4 days it came back again.the garage says he will charge again. the belt is also making a squeaking noice when i turn the demister on/please advice

Answer
Hi, Manoj.  Without additional information, it's impossible for me to tell you why the check engine lamp is on.  All this lamp means is that something monitored by the engine control module (ECM) is incorrect.  To assist you in the nature of the problem, I'll need the diagnostic trouble codes from the ECM and, if the vehicle has an automatic transmission, transmission control module (TCM).  These codes will need to be obtained using a code reader or scan tool capable of communicating with these modules on your vehicle.  In addition to this information, the year and model of the car will be of assistance.

As to the squeaking noise, I'd expect that the alternator belt is loose and needs to be retensioned.  Since I don't know what vehicle you have, I'm guessing that this belt is manually tensioned on your car.