Howdy folks. Hoping somebody can help me out with this, my first problem on our new-to-us 2006 Accord. The car has 30k miles, it's an EX-L with the 4 cylinder and stick shift.

The CEL is on and the scanner reveals code P2183 "engine coolant temp sensor 2CKT range/perf", as well as a pending code P0128 "coolant temp below thermostat regulating temp". The freeze data showed the coolant temp being the same as the intake air temp, FWIW.

The car behaves quite normally, warms up quickly, blows plenty of heat, etc. This leads me to think perhaps it's the sensor rather than the thermostat?

Anyway, it looks like there's a coolant temperature sensor on the lower, passenger side of the radiator. But I've read references to this car having two sensors, and I don't want to throw parts at it if I don't know that I'm even looking at the right one. Also don't want to throw a sensor at it if it may in fact be the thermostat just on the edge of proper operation.

Any thoughts? Thanks,

jeff

 

Geez, I missed this one. I just saw it on TSN.
I concur with what Gene N told you, except I'd look around to rule out a wiring problem to that sensor. If the sensor goes to open-circuit, the ECU might default to the air temperature. Watch the freeze data & unplug that sensor.

I'll try to remember to look it up in my Helm book tonight. There's probably a table of resistance vs. temperature.

 

Sensor 2 IS in the bottom of the radiator. Starting in 2005 it's an actual sensor, not a fan switch. Fan control is done by the ECU.

The Helm book talks about watching scan data (as temperature) & comparing with the actual temperature of that sensor.