My friend emailed me with a problem and maybe it's a common one someone here would know what it is. This is what he asked me

I have been trying to figure out a problem with my honda. I bought it a few months back as a daily beater. Its a 90 Honda accord. I an having a problem with the cooling fans. The condenser fan works fine when the A/C is turned on and when the engine temp gets to 210 it turns on like it should. The radiator fans does nothing at all. It is supposed to turn on at 189 degrees. I have replaced all the relays and checked all the fuses. I have ran the fan off the battery and it runs. however when running the car it will not turn on. All the relays are clicking when they should however the fan does not. It seems as though I am not getting power to this fan. Does anyone know where the fan timer control unit it or anywhere else I need to look. The fan temp switches also work. I am at my wits end and this car is not worth taking into the shop and spending hundreds of dollars on.

I have a manual for it, but it only helps for the general stuff.

I pulled all the fuses and checked them, replaced them, metered the fuse block itself.. all good. All relays click.. I am think it is the fan timer control box, have NO idea where it is...

 

Here's a couple links that should be of help for you
Fan schematic
And then you might need this one
Fan timer unit
If you need more help repost.

 

Thx..I'll pass it along

 

by the way both fans should come on at the same time with the a/c on and when coolant reaches the set temp of the fan switch ,, one does not come on at 189 and the other at 210


so,....... fuses and relays are ok.. have you tested the fan switch located in the thermostat housing ??.. there is a green plug with 2 wires going to it,, unplug it and jump those 2 wires together ,, engine running or key on ,,,,,