bigTom

which one is used for what... i was looking at my head and those 2 are there... which one does the water temp guage read off of?

b18bturbo

it reads off the one from the head next to VTEC solonoid is what i thought. But i know there another one in there to but i never paid much attention to it. I think thats for the fan temp control

LsTurbo91

the one with a single connector is for the water temp gauge in the gauge cluster. The other with the 2 wire green connector is the sensor that the ECU gets the input from.

VaporTrail

^correct^ The ECU also determines from this sensor when to turn on the cooling fans.

Xerxes

On my car and i thought on most b-series hondas, the cooling fans are controlled by the thermoswitch, which is just a mechanical device that shorts its terminals together when the temperature goes above a certain point.
I thought the ECU only used the temperature sensor for stuff like cold idle control, cold enrichment, and cold start vtec control?


-Xerxes

LsTurbo91

Actually there's 3, 2 in the head and one in the block near the oil pressure switch is the fan switch you are talking about. As for the idle control thats a different one and that is controlled by the IACV on the intake manifold.

dustin

I think that's the oil temp sender.... I don't think newer B series blocks have them(94+).

LsTurbo91

I think your right, I remember it was blocked off when I swapped the 94 LS in, I needed like a 27mm or close to that to get it out and screw in the sensor.

dustin

We just didn't hook it up on my friend's 97 LS -> 91 chassis swap....

But his radiator fans come on randomly when the car is turned off now

bigTom

good job

note to self; dustin is a wiring king! jk

LsTurbo91

hehe, that sounds about right, because I know the oil temp switch works when the car is off and if per the manual if the oil temp is a certan degree it will turn the condenser fan on, or the main fan.