Hi. We have an 09 G37S. Long, but I want to cover details.

Received car from a friend after it sat for about 4 years. We just replaced the clutch ourselves (not easy when you don’t have a lift). After driving it started to bog down. Saw that it started to over heat. Added around 2 gallons coolant. No, we didn’t check the level when we got it.

temp went back to normal.

Two days later, it started over heating when at idle. I thought it was the thermostat and put a new one in yesterday. Very easy job by the way. That didn’t take care of it.

after driving around for about 15 minutes, parked in driveway. Temp started going up after about 2 minutes of idle.

Does go down when heat turned in full blast.

popped the hood, noticed the fans not coming on. not sure if I need to check relays, fuses or fan motor. Don’t know where to start.

thank you in advance!

 

Bleed the cooling system thoroughly?

 

I think so. I did not see a bleeder valve. I left the caps off while after adding coolant and put it back after the bubbles stopped coming out. Is there a different way with these cars?

 

That's not enough to bleed it thoroughly. You likely have air pockets in the system.

Either use a vacuum fill device or one of those lisle burping funnels. Make sure the thermostat opens and fans come on. Look through the DIY section for a how too thread. Pretty sure one was posted.

 

Do any of the fans come on when the AC is turned on?

First, you should run the IPDM/er module self test. This will automatically tell you if there is a problem with the fans.



If the fans DO NOT come on at all with the self test, then you will have to check the fan motors, module, PWM (fan) relay, wiring, etc. If the fans DO come on, then you have to check the coolant temperature sensor, coolant, water pump, etc.

In my case ('08 Coupe) both of my fans motors were dying/dead (killed by beach sand). Easy replacement.

However, I do agree with what JSolo said. For whatever reason bleeding the air out of the cooling system in these cars can be a royal pain. Double check for air bubbles.

Hopefully the above will give you some starting points.

 

Excellent information. Will try this when I get home tonight. I will keep you informed of what I find out.

thank you so much!

 

Got home just now and re read the instructions. Stupid question. What is the drivers side door switch? What do they mean?

also, I did let it run and switched on the AC. Fan did not come on.

 

Open the drivers door. Look for a round, black "button" on the door jamb. This is your door switch.

 

Ran the test. Fans did not come on.

 

Both were dead? Are you able to turn them by hand? When I had this issue, as a second test, I hooked up a set of jumper wires directly from the battery to each fan motor (ensuring polarity) to test the motors. Both of mine were dying/dead.

If none of your fans show signs of life you likely have a issue with either the fan relays or the fan module. Most you can do is unplug everything, check connections for corrosion/dirt, also check wiring for cracks/damage (after sitting 4 years there's no telling what was living in that engine bay), plug everything back in and see what happens.

If you haven't already, you should download a copy of the factory manual for your car as this will help you diagnose/repair issues: G37 FSM

 

I can turn them by hand. They did not come on at all. I have been searching, but can not find a good picture of the relay location. I found the fuse box, but the menu does not make sense as to where the relay is supposed to be. I have a meter and i was going to test it. I downloaded an owner’s manual, but that didn’t help. Just frustrated because o don’t know this car. I can work on things, but I need to know where they are located.

 

I downloaded your link. Found the control module. Thank you!!! Still not sure if the relay. I want to test both. The diagnosing is the hardest part.

 

It is all good- we all had a learning curve at one point...

Directly in front of the battery is a long, rectangular box. This is one of the main fuse boxes. Inside there should be a 30amp fusibile link for the fans. Check this first.

Facing the battery, there is another thin, black, rectangular box along the left edge of the battery box area. This is the relay box (PWM is for the fans).

Directly to the left of the battery is a large, rectangular box. This is the Intelligent Power Distribution Module/Engine Room (IPDM/er) which is a really fancy integrated fuse/relay array.

 

Wonderful!! I’ll start checking things out tomorrow. Thank you! Will post what I find...or I may have to ask another question.

 

Well, tested everything and all works well. I believe the thermostat was the original issue. I do believe there still air in the system. Drive it hard for a couple hours today...interstate and town. Needle didn’t nose from the half way mark.

Thank you for all your help!! .