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Please help me out. Can you tell me what sensors are these on the back side of the water pump?
Im trying to build a digital gauge display with a bunch of sensor, but first Ii need to figure out what all the sensors that I can tap into. Im guessing one is a temp sensor but, my radiator I believe already has a temp sensor. Any assistance would be helpful. Thank You
As stated, there are no temp sensors in the water pump housing, unless you have a GSL-SE. There are also no temp sensors in the radiator.
The coolant temperature sender is on the left side of the engine between the heater hose and the oil filter. Your display would have to be able to work with a single-wire sender to use it.
GSL-SE had a sender in the water pump housing where the themoswitch is in 12A cars. Its resistance is very cloae to standard GM units, about 10F different.
It's amazing to see the difference in temperature between the two. The factory location is at the hottest part of the engine, the water pump housing location is more of an average and not really relevant if you care about engine health.
The coolant temperature sender is on the left side of the engine between the heater hose and the oil filter. Your display would have to be able to work with a single-wire sender to use it.
And 12 years ago my coolant temperature sender had failed and was reading low, but I had a leak in the radiator which meant it was overheating. The result was very drastic engine failure Fall 2013. I joined this forum Dec. 2013. With the help and guidance of the membership I successfully rebuilt the engine.
I'm not even proficient with the different Rx7 first generation models.
There is another forum, "Old School and Other Rotary" below the 1st Generation Specific on the main list. I did peak and there are year 2025 posts mentioning cosmos.
As to the sensor on the top of the radiator in you image, most likely that is the coolant level sensor. If your coolant goes low a warning light shows on the dash and I believe a buzzer goes off. I have no idea what the one on the right side is for.
The two pin device in the water pump housing is indeed a coolant temperature sender. It will have the same resistance values as GSL-SE or FC. Very close to GM sensors but not quite.
in the radiator, the device in the middle is the coolant level switch. Very simple device, it's a plastic housing and the wire gets sent power by a control module. It grounds through the coolant. When the coolant is low, it loses ground and the control module turns the light on (sometimes with a very loud/annoying beeper)
I don't know what the thing on the left is, I've never seen one before. Possibly a switch to cut A/C off if the engine is overheating? It doesn't go to the gauge.
