[hteamer]

So I ran into an issue with my cooling system and I’m at a loss.

A little back story: I had the battery replaced and registered a couple of days before the problem began.

Typically I drive only freeway and never sit in traffic. After replacing the battery I got stuck in a bit of traffic and got hit with the yellow cooling issue light.

The torque app said my coolant temps had shot up to 120c during this. Once I got up to speed the problem went away.

Once I got home I let the car cool then tried to replicate the problem the next day but no dice. No overheat. Nothing.

Then a couple of days later it happens again but I’m close to home. I pull in the garage pop the hood and notice the cooling fan isn’t running.

Shut the car off then try to turn on the ac and the fan turns on…

Next I use the scan tool and it initializes the fan, run the water pump bleed, that runs for the full 12 mins. Everything seems good.

Couple drives later everything is good then about 30 mins into my drive the overheat starts (happens at a stoplight).

I notice again the cooling fan isn’t on. Pull the car over turn it off then use the scan tool and it turns back on!

I don’t know what to do.

Is it my fan?

Is it my water pump?

What the hell…

[GoRomeo]

Originally Posted by hteamer

So I ran into an issue with my cooling system and I’m at a loss.

A little back story: I had the battery replaced and registered a couple of days before the problem began.

Typically I drive only freeway and never sit in traffic. After replacing the battery I got stuck in a bit of traffic and got hit with the yellow cooling issue light.

The torque app said my coolant temps had shot up to 120c during this. Once I got up to speed the problem went away.

Once I got home I let the car cool then tried to replicate the problem the next day but no dice. No overheat. Nothing.

Then a couple of days later it happens again but I’m close to home. I pull in the garage pop the hood and notice the cooling fan isn’t running.

Shut the car off then try to turn on the ac and the fan turns on…

Next I use the scan tool and it initializes the fan, run the water pump bleed, that runs for the full 12 mins. Everything seems good.

Couple drives later everything is good then about 30 mins into my drive the overheat starts (happens at a stoplight).

I notice again the cooling fan isn’t on. Pull the car over turn it off then use the scan tool and it turns back on!

I don’t know what to do.

Is it my fan?

Is it my water pump?

What the hell…

But did you actually use the Torque app to read the fault codes? Pls post a screen shot of the fault codes.

[GoRomeo]

Originally Posted by GoRomeo

But did you actually use the Torque app to read the fault codes? Pls post a screen shot of the fault codes.

Also Need engine info miles model etc

[hteamer]

GoRomeo
Year: 2006
Model: 325i
Mileage: 266,477 miles
Manual Transmission

The torque app reported 0 fault codes.

Here’s the diagnostic report from the launch bmw scan tool: https://usait.x431.com/Home/Report/r...us/timezone/-8

I didn’t see anything regarding the cooling system.

Thanks for your help in advance!

[hteamer]

Replicated the problem today… still no fault codes.

What I did learn is that when the problem happens I can not manually activate the cooling fan or the water pump.

Let the car cool down then started it back up and cooling fan works again…

I’m wondering if this could be an issue where the wiring is getting too hot and causing the ecu is going into protect mode for the electronics? I have an electrical background but in communications repair and know that some modules have these protections. Does this apply here?

I don’t know… this is blowing my mind.

Inspected the wiring for the fan connector and the ground wire is exposed a bit. I’ll take a picture and upload.

[StradaRedlands]

Weird you aren't having any fault codes... I would maybe guess coolant temp sensor, although I think when they fail the fan goes on full blast. I'm not good at diagnosis though, hopefully you get some more feedback!

[hteamer]

Thanks StradaRedlands

I suspected this but I always thought that fan motor would spin even with a bad cts.

They’re cheaper than replacing the fan though so if I get too stumped I might go to tossing parts cheapest to most expensive.

[GoRomeo]

Originally Posted by hteamer

GoRomeo
Year: 2006
Model: 325i
Mileage: 266,477 miles
Manual Transmission

The torque app reported 0 fault codes.

Here’s the diagnostic report from the launch bmw scan tool: https://usait.x431.com/Home/Report/r...us/timezone/-8

I didn’t see anything regarding the cooling system.

Thanks for your help in advance!

Do you think you can try a different scanner one that can that actually read BMW CODES?

Wow I just realized you have more miles than me on my 06 E90 Way to go!! 😄

[hteamer]

GoRomeo
Lol yeah I’ve always said I’m driving her till the wheels fall off (almost happened, I snapped two struts hitting a dip on the way to Vegas) or there’s flying cars. Both haven’t fully happened yet so I’m keeping her.

This scan tool does read bmw codes. Only one that consistently throws is the ibs code 2e8e

[hteamer]

StradaRedlands GoRomeo

Closing the loop here! Wanted to drop thank yous to both of you and let everyone know the end experience in case they run into this issue.

Shortly after my last post the fan started having more trouble kicking on. You could hear the motor try to initialize but not catch.

Ordered a replacement, went on a vacation and just popped it in tonight.

So far so good. No codes (still, none ever came up), ran passing all actuation tests, and car has not over heated in the 30 minute test drive.

Looks like with intermittent fan failure sometimes you gotta just wait till it dies or rule out every thing else because there may not be any codes thrown.

Thank you again!

[GoRomeo]

Originally Posted by hteamer

StradaRedlands GoRomeo

Closing the loop here! Wanted to drop thank yous to both of you and let everyone know the end experience in case they run into this issue.

Shortly after my last post the fan started having more trouble kicking on. You could hear the motor try to initialize but not catch.

Ordered a replacement, went on a vacation and just popped it in tonight.

So far so good. No codes (still, none ever came up), ran passing all actuation tests, and car has not over heated in the 30 minute test drive.

Looks like with intermittent fan failure sometimes you gotta just wait till it dies or rule out every thing else because there may not be any codes thrown.

Thank you again!

Cool but do you see the fan cycling?? It should turn On and Off by itself every 5 min or when idling amd reached certain temperature.