Newly registered member here (although I have been lurking for a long time). Vehicle is a 2002 Discovery with ~107k miles on it.

I recently replaced my water pump and thermostat (as well as some hoses and clamps). When I went to start up the car, it would not start. I figured it was a dead battery and I was able to jump it to get it going. I immediately was hit with the flashing M & S lights and was put into limp mode. I figured that was caused by low battery voltage and I needed to replace the battery.

Put in a new battery today and still have the exact same issue (and my old battery even tested good). The battery is fully charged but I cannot start the car (the relay doesn't even click) unless I jump it.

Any thoughts? I was thinking I may have some sort of ground fault somewhere. Or maybe the voltage regulator on the alternator is blown (though I assume that wouldnt impact the vehicle starting).

 

Check your ground cables. Get the alternator tested.

 

i would put my money on bad alternator.