AUM

I was looking to put in a water temp gauge and install the sensor in the thermostat housing. I found that there is already a sensor installed in the spot that is suggested to place the temp gauge one. After doing some searching I found that on an automatic the termoswitch is located here. Here is the post I found.

https://www.rx7club.com/showthread.p...itch+automatic

So my question is how many thermoswitches are there on an automatic?

Everything else I have read says that the themoswitch is on the back of the thermostat housing under the thermosensor. Is there one here also on an automatic?

Why is the thermosensor on the front and where can I install my temp gauge sensor?

KevinK2

the one on the front is for autos only, and changes to early 'lock-up" if coolant gets too hot, over 239F.

eng themosensor and fan thermo switch are both behind the pump hsg. gage temp sensor is by oil filter.

AUM

KevinK2 thanks for the info.

The sensor in question is the one circled. The wire for it goes back into the engine wiring harness but the end that connects to the sensor looks made up of a female spade crimp folded over. I was looking in the FSM in the parts fiche section, Body A on page 3-H 6 it looks like this automatic transmission sensor should go in the hole that is plugged by the filler neck. Is this correct?





Also if you look closely the plug for the low coolant sensor is not plugged in. When Mazda put the motor in they couldn't figure out why the coolant buzzer and light kept going off. I posted this problem back then and told Mazda of the advice I received and they said they fixed the problem. What they did was to not plug in the wiring harness side of the low coolant sensor but run their own wire to the wiring harness shown in the second picture (the circled part). They soldered this wire to a brown wire with a white strip. Is this correct?

I thought that the low coolant sensor wire connect from the wiring harness to the ignition harness. What is this Brown and white stripped wire?



Any help or ideas would be great. I want to clean up Mazda’s mess. Also any ideas on where I can place my Defi temp gauge sensor in the thermostat housing if I can't move the existing sensor in the front?

KevinK2

Verify low coolant light works.

Could delete the trans water switch, put gage sensor there. If it gets over 240F, back off and cool down.

AUM

KevinK2 thanks for the help, I had thought my question was dead and buried since it was so many pages back last time I looked.

I had planned to drain a bit of coolant below the level sensor to see if it would trigger the sensor. If it doesn't I will ground the sensor wire from the wiring harness and see if the problem is the stock wiring or the sensor. I'm thinking they just didn't connect the other end of the wire under the intake elbow, but I don't want to take this off before I look at all the other possibilities.

So if I replace the transmission water switch in the front of the thermostat housing with my defi temp sensor I won't trigger any warning sensors? If this is the case then that’s a plan.