Hello,

High level question: What causes a constant buzzing noise in the car with the engine off and the ignition on?

Details: I have been doing work on my newly purchased '94 rx7, and found something of interest. My fuel temp sensor didn't have 5V, and I traced this back to a disconnected "Electrical Load Control Unit". Of course, when I plugged this connector in the car immediaely started buzzing at me! The fuel sensor now had 5V, but I couldn't make the buzzing stop.

When I turn the ignition to "ON", it takes a little while for the buzzing to start (maybe 15-30 seconds). As a guess, I monitored the batter voltage while doing this, and it seems that the buzzing starts when the battery drops to ~12.76 V (from 13 with the car off). I can't start my car (the intake is apart right now), and I want to know what this might be before I put everything back together again.

The only thing I can see that might cause this is low coolant, but I don't know if the electrical load controller makes this system work or not. The buzzer did not go off previous to me plugging in the connector, and the coolant level didn't change (though it was a little low).

David

 

Buzzer is typically low coolant

Spend some time in the 3rd gen FAQ thread. Its the first thread stickied in this forum. Look under the C section for coolant system and read the threads in those links.