Hello! New here and relatively new to rotary cars. I have a '93 RX-7 which recently developed the common add coolant buzzer problem. I did a bunch of searching on here and found some good info, however, my problem seems to be a bit unique. It doesn't need coolant, it doesn't have air in the lines, and I already replaced the sensor. It also has a freshly rebuilt engine; runs great. So, I believe there's a break somewhere in the wire for the coolant level sensor. Here's what I'd like to know:

- Where does the coolant level sensor wire route into? I.E. how far back in the harness, and where in the engine bay will I have to trace it to find a break? I can see it meets the harness by the intake, but then it splits and I can't see where it goes.

- Is there more than one coolant level sensor, or just the one in the water pump housing? Maybe more than one wire? I read some stuff about there being another connector by the power steering pump.

- Where on the ECU does the coolant level sensor connect? If I can't find the break, I plan on just running a new wire. Note, I have a Power FC, if that affects anything.

- Is there anything else that can cause this buzzer to go off erroneously?

I have looked at the wiring diagram in the FSM, but couldn't quite make sense of it all---not as though you can just search for the circuit you're looking for Pictures would be extremely helpful as I'm more of a visual learner. Thanks in advance! This car has several small issues I'll need to correct, but this one is most important

 

im in the same boat as you man. i hope you find the answer. i will be following with you.

 

Just got a rebuilt done and have the same issue. All air out with new sensor, still buzzing

7k rpm and Oil level connector/sensor also make the buzzer go on.

 

Find a brown and white wire, aether ground it or connect it to the t stat housing. The wire should be in the alternator harness. hope this helps.

 

This should help:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fd-annotated-harnesses-front-instrument-dash-rear-floor-%2Aindex%2A-971065/

 

the wire for the coolant level sensor runs thru the engine harness but it doesnt endup at the ecu, instead it makes a loop and ends at the altenator harness, there are two disconect points for this sensor.

1. at the coolant level sensor, front of water pump housing.
2. at the altenator harness, this is a single wire plug located behind power sterring pump area, above ac compressor.

 

Thanks everybody for all the great help. FC3S1991 hit the target.. the harness coming accross the front of the motor from waterpump to the powersteering unit has a single wire that connects to a single wire from the driverside harness that also has the powersteering and AC connectors.

Connector was completly hidden.

 

hi all
i have the same problem with buzzer and the red light at water,I bleed the system and it still the same and when i check the pan sensor i see the wire is broken and the connector is missing. where i need to connect it and i have another 2 wire from the wire loom broken 1 it is blue whit orange or red spot and 2 is blue whit a yellow line wires are above Starter motor.
thanks in advance

 

can someone take a picture of the connector on the alternator side!

 

Pics would be great! I'm having the same issue here, these stupid harnesses are like eggshells and I'm afraid to go poling around in the wrong place

 

Is this for the coolant level sensor wire? Just finishing my install, just cant find the male to plug into the single wire female connector behind the power steering pump (see picture).

 

No, but it might be for the power steering wire!