A/C Compressor and main radiator fan both quit at the same time. What are the odds?

[Jeep_Riot]

2015 Subaru Crosstrek. The main radiator fan does not work. If I idle the car the temp goes up, but the fan does not turn on. It normally turns on around 203 degrees. I let it run up to 215 to see if it turned on and it didn't.

The A/C light is lit on the control knob but the compressor is not running. The sub fan does not work, either. The High and Low side are both hot to the touch when the A/C is on. Only hot air comes out of the vents. Everything worked fine yesterday.

A OBD scan shows no activity from both the main fan relay and the sub fan relay. The both show OFF. Could the main fan relay be the problem? And if so, is that why the compressor is not turning on. In other words, is there something that tells the compressor not to turn on if the main fan does not turn on?

Thanks.

 

[Chris142]

See if you have power and ground at the fans

 

[SC Maintenance]

Not sure if this helps, but my Nissan had a electric fan go out - and the A/C wouldn't get cold at idle even though the engine never got hot. AC worked fine going down the road though? After reading the manual I realized the electric fan was kicked in by the A/C to move air across the coil when the vehicle was not moving.

Does your AC work at all when driving?

I agree - ohm out your fan wires and go from there.

 

[KrisZ]

You need to diagnose and fix the radiator fan issue first. After that if the compressor is still not kicking on, look into the AC system.

 

[Jeep_Riot]

Thank you for the replies. I’m at the shop as I type. It looks like the evaporator gave up the ghost and expelled all the refrigerant.

Two questions:
1. How can having no refrigerant in the system cause the coolant fan to not kick on? I can understand the sub-fan not kicking on, but I have trouble wrapping my head on why the main radiator fan didn’t work.

2. Are GPD evaporators any good? That’s what they use.

One more thing: I miss the days of sitting in a waiting room chatting with people. **** cellphones.

Thanks.

 

[Astro14]

A thought - on my 18 year old car, the modules are all networked. 34 modules on a networked bus.

A fault in one module causes other modules to respond. E.g. radiator fan failure detected the ECU can cause the climate control module to keep the AC system compressor off until the fan fault is connected.

A climate control module fault can cause the radiator fan to go to full high, continuously, since the ECU doesn’t know what demands are being placed on the cooling system. That actually happened on my car. The fault was actually a power interruption to the front right SAM (signal acquisition module) which controls lighting and other functions. The climate control is separate, but that SAM dropping off the bus caused other modules to respond.

I wouldn’t be surprised if similar logic exists in your much newer car.

 

[mk378]

In many newer designs, the fan does not start because of A/C unless the A/C high side pressure reaches a certain amount. This avoids the fan running unnecessarily when the car is moving fast enough to push sufficient air through the condenser.

 

[Marcozi]

Typically, the radiator electric fan is controlled by the engine computer. As noted above, all of the modules i the car networked. If the engine computer get a "low/no refrigerant" signal from the refrigerant pressure switch, nothing will work. Also, if the engine computer notes that the electric radiator fa isn't work it won't enable the AC system to operate.