2016 Legacy cooling/radiator fans always on

Joined
Jan 10, 2023
Messages
9
Reaction score
0
Rebuilding this car after a front end crash, replaced the radiator, active shutter, thermostat, etc.. Now even if the engine is cold, once I start it, the fans come on.. Even without starting the engine, if I put the car on the on position, the fans come on..

The active shutter works fine, I can't figure out why the fans would come on on a cold engine.. From what I can see, all the connections are back in place, so I don't know if it's a relay or fuse, or maybe a bad thermostat (even though it's brand new)..

And the A/C system is off, so that can't be it..

Any ideas?
 
Look at the image, choose the correct model.
 

Attachments

  • BzkNZEcWmW.png
    BzkNZEcWmW.png
    2.7 KB · Views: 10
Look at the image, choose the correct model.

2.5 Limited with eyesight..

I checked the 3 relays in the engine fuse box, when I took them out, the fans stopped, and when I put them in, the fans started.. This is with the engine off, but the car in on position..
 
Read the schematic:
Main Fan Relay 1 and Sub Fan Relay are powered by two fuses.
Main Fan Relay 2 is controlled when Main Fan Relay 1 is closed.

The ECM controls the relays when the temperature is correct or AC is engaged.

Relay contacts can be internally shorted / fused together or control circuit shorted to ground.
Relay control (wiring) to the ECM can be shorted to ground.

The ECM can also have a defect.

Test each relay first.

https://www.grainews.ca/machinery-shop/how-to-check-for-a-faulty-relay/
 

Attachments

  • 2016 Legacy 2.5L Limited Fan Control.pdf
    50 KB · Views: 6
Read the schematic:
Main Fan Relay 1 and Sub Fan Relay are powered by two fuses.
Main Fan Relay 2 is controlled when Main Fan Relay 1 is closed.

The ECM controls the relays when the temperature is correct or AC is engaged.

Relay contacts can be internally shorted / fused together or control circuit shorted to ground.
Relay control (wiring) to the ECM can be shorted to ground.

The ECM can also have a defect.

Test each relay first.

https://www.grainews.ca/machinery-shop/how-to-check-for-a-faulty-relay/

excellent, thank you so much.. I have some diagnostics to do today.... I'll also test the relays themselves.. I think what happened in the accident is that the upper radiator hose got sliced by the serpentine and spewed coolant all over the fuse box, and the fuse box itself was crushed.. I'll examine all those wires and connections too..

your help and diagram is much appreciated..
 
Replace the entire fuse box if it was crushed to prevent future issues and prevent a fire.

The fuse box internal circuitry can not be repaired.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Members online

No members online now.

Forum statistics

Threads
13,888
Messages
67,364
Members
7,363
Latest member
Mustangman35

Latest Threads

Back
Top