OK

I have a schematic for a '89 2.6 in the 124 chassis,so it might be close
According to this , it can not be fuses cuz both relays use common feed fuse for both fan load and relay primary coil.
So, do this
key ON
jumper pressure sw .. [ be careful here that you are jumper correct sw , there are 2. The one you want has brn. pigtail wires .. don't jumper sw, but rather the wires leading back to firewall] you can just lift sleeve for wire connectors and jumper while leaving sw in circuit. That should get low fan .
If fan does not come on, but you can hear the relay clicking, than we have relay circuit.
Now , try this
No key needed for this test
run jumper wire from bat + to the dropping resistor .Touch the side with 2 wires on it .. this will give high fan.. then go to side with one wire on it .. same deal, but you should have low fan .. if not , you have bad resistor or connection there
I will see where the relay is located for the 124 2.6 and get back to you
try the above