Coolant fans appears to not be turning on
 

As best I can tell the coolant fans aren't turning on, and I can't figure out why.

Warmed up the car until Torque said engine temp was 217F, and the fan still didn't turn on.

No AC or any environmental controls installed.

I have the beastronix nanny v2 with the dedicated fan switch and that will also not turn on the fans.

Mishimoto radiator and Mishimoto fan shroud.

Any ideas?

Well, the first thing I would check is the fuse(s) that control the fans.

Does your beast thing still rely upon the OEM fuse to run the fans .. ??

The next thing I would do is to run a hot lead directly to the fan motor(s) and see if they will run.


humfrz

Both 25 amp fuses appear to be intact. The number 3 and number 11. I will hook up direct power to the fans, but I'm really doubting both are bad.

How's your a/c? It will always use a fan. If the fuses and wiring are all good...

You could also read voltage when the fan should be running to see if its getting there. Just keep fingers away from fan blades that could move...

No AC, no AC controls. Lets just say this vehicle is not for comfort.

Is the fan switch at 212F or is something else. I've only found some information alluding to the switch temperature.

Fan operation is controlled by the ECU. It's supposed to kick in just above 95C (203F) See test procedures in the service manual. Link's in my sig line.

FA20 COOLING: COOLING FAN SYSTEM: ON-VEHICLE INSPECTION; 2013 MY FR-S



https://i.imgur.com/rWusCfZ.png

I've been out of town and only was able to start working on this.

All relays work.
All fuses are good.
The fans spin with direct power.

Pulling the coolant temp sensor fan does nothing except peg the temp sensor in the car.

Using a volt meter the trigger signal is never sent, it always shows 12v on both sides of the relay connection, hence it never triggering.

What would prevent the ecu from sending the signal?

Have you tried disconnecting the 86Nanny?

If disconnecting the nanny doesn't help, try the ECU reset. Disconnect the battery and step on the brake for a few seconds to drain any residual charge. Reconnect battery. Leave the nanny disconnected.

If that doesn't work, find someone with techstream to help you test the ECU or take it to the dealer.

As kodename47 said disconnect any additional wiring

Are you running stock tune, ??, Have the fan activation tables in tune been changed or disabled ??

If ecu outputs never change ecu may have been damaged by additional circuitry

Ground?????

Shit never mind you stated runs with direct power.

The 86nanny wasn't connected for any testing.

As far as I know, no tune has been applied to this ecu yet. I did throw in another ecu to see if that would help, though of course the car won't start with another ecu.

ECU is clear of codes. I have techstream but not the 2.x cable so it won't let me do the diagnostics

Post in the norcal sub-forum. Some cool people there that I bet would be glad to hook a comrade up.

Hate to raise this from the dead, but I'm wondering If my fans are working now. Im in the same spot - no ac compressor or ac controlls in the car, and using an 86 nanny. The fuses and relays all seem to be good. Sfruski - did you ever sort out what was happening ?