I have an 89 Si. My cooling fan doesn't turn on at all. The temp switch (attached to the engine block) works fine, the temp guage is accurate, I checked the fuse under the dash, tested the relay for continuity (it made a clicking noise when the C and D terminals were connected via speaker wire to the battery), and I connected the fan directly to the battery to make sure the fan motor wasn't bad.

Why else would the cooling fan not turn on when the temp guage is already 3/4 the way to 'H'? Is this something I could do myself while following the shop manual?
Thanks!

 

i would get a mechanical water temp gauge and see if your getting the same results as the stock gauge. opperating temp should be around 180-200 depending on your thermostat. did you check all the grounds? clean off the bolts and sand down the paint that it grounds to. hopefully that will work

 

also check the connection that goes to your fan. and check the wiring also

 

 

great info ^

On the back of the block, the coolant temp switch works by allowing continuity between the terminals A and B, once it has reached a high enough temp (about 190 F).

There are 2 wires going to the coolant temp switch:
Black = Ground (verify a good ground)
Yellow/green = 12 Volts+ (when key is in ignition)

When the switch reaches temp, it allows the Yellow/green wire to contact ground.
You can simulate the switch being activated, by directly grounding out the Yellow/green wire (with the key in the ignition). If you ground out the yellow/green wire and the fan comes on, then it is probably a bad coolant temp switch.

 

great info

 

It's the relay...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wm07 &raquo;</TD></TR><TR><TD CLASS="quote">It's the relay...</TD></TR></TABLE>

Thats what I was going to say as well. They can be intermittent

 

That's great info. Man...I miss driving it. Have great weekends all of you!

 

nice work dudes