lingerbw... & anyone else who cares

I don't know if I'm screwing up the names that Honda picked for these things. It's also based on my cars, so a '90 Accord might be different, but here goes...

The fan switch is just that... It's an on-off switch that turns on the fans at some particular temperature. On my Hondas it's got a plastic connector with 2 wires. It's screwed into the thermostat housing so it sees the water returning from the radiator.

The ECT (engine coolant temp.) sensor is wired into the ECM, & has a variable resistance with temperature. It's not just on & off. And it has nothing to do with running the fans. But it looks kinda like the fan switch, it has a plastic connector with 2 wires. It's located near the upper radiator hose so it sees the hot water leaving the head.

The temperature gauge sender is also near the upper radiator hose but it only has one wire. This sender is ONLY for the dashboard gauge. None of these sensors or swithces 'share' information with each other.

I've heard about some older Hondas with a second fan switch (located where??) that has a lower temperature setpoint, that is only active after you turn off the car. I've never owned a car with one of those, so I dunno...