Why won't my radiator fan turn on?

tykempster · Jul 15, 2014

I got into a front end collision, made everything straight and replaced my radiator. When I do a KOEO test, my fan cycles through both settings, but with the engine running it never turns on and it will overheat.

My AC condenser is missing because it was damaged and I cut it out at the bracket so I can replace it sometime, but I don't think that should make the fan not turn on.

whiplash473 · Jul 15, 2014

Your fan is controlled by the CCRM which is the box in between the radiator and the coolant overflow tank. I'd yank it and test all the pins.

rz5.0 · Jul 15, 2014

I have thread some where on here with some procedures to check the fans

daltonduree · Jul 15, 2014

if it runs for your key on engine testing then check the wiring from the computor to the coolant temp sensor. our cars have two. one for the gauge and one for the computor. check the sensor it self also

CC'S95GT · Jul 15, 2014

Well since the fans both work during the KOEO test that means the CCRM is working.
I would look at the temp sensors. There's 2. one for the computer and one for the gauge.

tykempster · Jul 15, 2014

The gauge on my dash rises but the coolant in my radiator is cold. Does this mean my thermostat isn't opening? It was brand new almost.

toyman · Jul 16, 2014

tykempster said:
The gauge on my dash rises but the coolant in my radiator is cold. Does this mean my thermostat isn't opening? It was brand new almost.

Correct, not opening. Is it installed the right way? Spring towards the engine (intake manifold),

ttocs · Jul 16, 2014

start simple, check fuses.... Check them all both under the hood and under the dash.

tykempster · Jul 17, 2014

My thermostat is definitely the right way, it worked fine before I wrecked. Is it common for an impact to make it stop working? It seems quite simple...

CC'S95GT · Jul 17, 2014

It depends on how hard you smashed the nose. You could have broken some wires or damaged the CCRM. Or broke the fan itself.

tykempster · Jul 19, 2014

Here is the damage right after, and now with the radiator support straightened as well as I could do. Frame was straight and it seems to drive great still, but obviously the fan needs to work.

I think my CCRM is ok because everything else associated with it seems fine. It cycles through the high and low speeds during KOEO fine, and the CCRM makes the usual relay clicks.

After running, the car's temp gauge rises slowly until it will overheat if I don't shut it off. If I open the radiator cap, the coolant is cold. I'm going to replace the thermostat tomorrow and report back.

CC'S95GT · Jul 19, 2014

you might have damages he water pump too. Broken shaft, deformed fins.

toyman · Jul 20, 2014

I assume the rad fans are still not coming on, correct? The ECT sensor should be taking care of this. Seems like there are a couple of things happening here that need to be sorted out.

tykempster · Jul 21, 2014

Put in a new thermostat. 180* was in there which explains it running cold always. Shoulda checked that before I put it in the first time. Battery was dead so I couldn't check it...nothing can ever go smoothly, battery was fine the other day!

tykempster · Jul 21, 2014

Put in a new thermostat but battery was dead today.  Had been fine until now so guess I'll get some cables and report back after that

CC'S95GT · Jul 21, 2014

I've been running a 180* stat for a couple years without any issues.

RichV · Jul 22, 2014

You may have air in the system as well. How about belt routing? Is the belt routed so the water pump spins correctly? Should be spinning opposite of the crank pulley.

Cold radiator is definitely a coolant flow problem, I'd fix that before getting into the fans. Is any part of your radiator getting hot? Have you run the car in idle with the cap off?

MustangChris · Jul 22, 2014

whiplash473 said:
Your fan is controlled by the CCRM which is the box in between the radiator and the coolant overflow tank. I'd yank it and test all the pins.

beat me to it.

tykempster · Jul 22, 2014

Belt should be fine, it never came off since the accident. Jumping the car tomorrow and charging the battery, will probably take it around the block a few times. Also installing new hood I got.