Another fan relay question....

[jimdigs]

..so I did a search and found helpful info. I went out to the car and pulled the wire to the relay in the thermostat housing with the key in the on position and the fan started like its supposed to. Earlier today I ran the car for about 20min. and the fan never came on, which is why I did the searching on here. The upper hose was nice and hot, the bottom hose took longer to warm up. So now that I know the fan is fine how do I know for sure its the relay gone bad or just that the temperature in the engine never made it to where its supposed to. My coolant is nasty and I do need a flush. I just bought a multimeter can I test the relay with it? I'm just learning with the multimeter and don't want to short anything out. I bought the multimeter to check my tps (throttle position sensor) but am waiting on a wire piercing probe. Anywho, anyway to check to be sure the relay is fine? thanks, Jim

[muleskinner]

From my understanding in the search if you unplug the senser at the thermostat housing and the fan comes on and your still overheating, then you have a bad senser.
Of course having nasty radiator fluid doesn't help either. I'd try flushing the system first & putting fresh rad fluid in.

[jimdigs]

From my understanding in the search if you unplug the senser at the thermostat housing and the fan comes on and your still overheating, then you have a bad senser.
Of course having nasty radiator fluid doesn't help either. I'd try flushing the system first & putting fresh rad fluid in.

I'll try flushing first. Gotta wait for the temp outside to get a little warmer. Still cold up here in southern Michigan.