I've recently changed my relay switches because the radiator fans weren't coming on (which was causing the engine to overheat on idle) and now my coolant light goes on when the key is in the on position (also makes a constant beep) and when I start the car it goes away after about 20 seconds. I don't know if this is relevant but I just installed a rx7fashion downpipe, hi-flow cat, and n1 catback. The car has 134,000 miles with 7k on new motor and turbos.

 

maybe it needs coolant!!

 

hahahah...............I wish, but there's plenty of coolant in there. Life sucks sometimes.

 

You may have kinked the water level sensor wire somewhere while you were changing the switches. The sensor is on the filler neck. There are two harnesses for the sensor under the hood. The first is obvious, but the other is hidden within a bundle of wires near the leading spark plug, front rotor. My car wouldn't stop buzzing at one time. I found that there was a leak of coolant from the bottom coolant hose clamp for the lower throttle body hose. It sprayed the harness and caused it to lose continuity. I sanded the brass spade, and female harness and it works fine now.

 

thanks for your reply, I'll check that wire first thing in the morning.