cars broke please help

[CMF_jordan donohoe]

Heya I drive a 1999 micra tlthe last few weeks its been guveing me trouble when I am driveing the lights go dull and the radio turns off the car slows down and so does the ac system turn off I changed the battery less than 1 year ago and I also changed the alternator but it has not sorted the problem any 1 know why please help thanks

 

[CMF_jesh]

The problem is not with the battery nor the alternator. When the engine is running, it recharged the battery even if the battery is flat.
Its a wiring problem, loose or poor connection? You have to check the output voltage of the alternator. It should around 13v with engine running.

 

[CMF_BigJohn]

Also, upgrade your grounds with nice thick cabling and ensure contacts points are all clean & secure.