lnlycrpr

there is a rectangular (green) and a round (black) sensor on the back of the water pump housing. what is the black one and what does it do, and how important is it? i accidentally broke it while removing the pump housing.

i need to know if that is something I can live without or if it is TRULY needed. I broke the wire right at the butt of the sensor, so i'm gonna be kinda screwed until I figure a way to fix it. thanks guys

lnlycrpr

the FSM says that it is a "water thermoswitch connector (A/T)" and that the green one is a "water thermosensor connector". its just the round black one that I broke.

is it safe to say that I dont need it?? I have a manual tranny. if anyone has dealt with this before i'd like to know what your input is.

HAILERS

In the COOLING section it shows a WATER THERMOSWITCH. It is shown with NO wires on it. It shows a figure taking a multi meter to the prongs on the switch. THAT switch is for the auxillary electric fan that some cars have.

So my question is, am I understanding you right when you say this switch has wires that are potted in the back of the sensor and a wire lead with a plug on it?

Maybe it that is so, there is a seperate sensor dedicated to the automatic transmission cars?

lnlycrpr

no. the switch only has 1 wire coming out of it. the switch comes from the main harness just like thermosensor. i'm not sure what it's for since my car is not AT.

section E-8 shows the two sensors on the back of the housing #10 & #11
10-water thermosensor connector
11-water thermoswitch connector (A/T)

thats what i have on the my housing. now since my car is a manual tranny, am I ok with out this switch?

lnlycrpr

has anyone had experience with the sensors/switches on the back of the water pump housing? i need to know if that switch is crucial or not.

it seems to be an aux switch for a fan, but I only have a radiator fan. does anyone know if I really have to have that switch.

NZConvertible

Only S5's have two sensors on the back of the water pump. The green one is the ECU thermosensor and is very important; the other one is the thermoswitch for auxiliary electrical fan. It switches this fan on if coolant temp gets to 205degF. IIRC the fan was fitted to Turbos and Automatics.

If you've got the switch then your car has (or once had) this fan. It's mounted in front of the A/C condensor above the oil cooler.

lnlycrpr

thank you for that answer NZ!!
i do not have a fan in front of my condensor so that is all i needed to know.
you have saved me a HUGE headache! the green sensor i have is fine. i'll disregard the black one. YOUR THE MAN!!!