Part # Help: fan/blower that cools ECM box

carboncow · Post by **carboncow** » 18 Apr 2018, 17:37

I think half the reason our ECM got nuked was I just determined that little fan is not working. Anyone got a part number?

Post by **oragex** » 18 Apr 2018, 19:07

Do you know why it isn't working? I would not expect this to fail but they do get a little stuck. Try kicking a bit the wheel see if it turns relatively easily. I also think it has a small resistor on it. Finally the wires and electrical connector are easy to check.

Can't tell the part no but it's around $150 at Volvo. Easier to source a used one that spins easily.

This fan should kick in in hot weather after driving for a while. Another way to test is to remove the ECM cover and feel how hot the modules got: if it burns the skin then it's a problem, but they actually do get pretty hot and can withstand some high temps.

I believe there is also a temperature sensor integrated to the ECM that will activate the fan past a certain temperature inside the ECM

As for the ECM, the main reason they go bad on these 2001 and up, it's water ingress at the lower connectors. It's quite easy to remove them from there without the special tool, and inspect the connectors on both sides.

Free2drive! · Post by **Free2drive!** » 19 Apr 2018, 07:25

That's helpful Orangex.
Apologies for jumping posts. I have a question. My ECU fan runs permanently while the car is in use all year round.
Is this operating correctly?
Thanks
Matt

Post by **oragex** » 19 Apr 2018, 07:31

Hi Matt, I suspect the weather in your area is not always very warm? My guess is a previous owner may have shorted the wires to the fan so it stays on at all times. Maybe he thought there was an issue with the ECM cooling. On my 2003 non turbo (petrol) the fan only kicks in when the outside temperature is above 15C and I drive the car for more than 30 min. In hot summer days (25C+) it would kick in faster, and also stay on for 1-2 minutes after shutting the engine off

The fan connector is located right near the ECM box on the engine bay wall.

Post by **jonesg** » 20 Apr 2018, 02:11

carboncow wrote: ↑18 Apr 2018, 17:37 I think half the reason our ECM got nuked was I just determined that little fan is not working. Anyone got a part number?

Check the fuse in the engine bay.

Free2drive! · Post by **Free2drive!** » 20 Apr 2018, 02:25

Thanks, got it out looks untouched but might be internal fault.
Here's my other possibly related issue.
If I run around with ECU box unclipped then the car runs fine. When I button down the box by the headlight I get canbus issues: Brake stop safely, transmission service, no speedo, no rev or temp gauge. Eventually no start.

I'm thinking the box is pinching wires or a connector is broken and to be honest I'm fearful of opening it up.
Matt

Post by **jonesg** » 20 Apr 2018, 03:37

Free2drive! wrote: ↑20 Apr 2018, 02:25 Thanks, got it out looks untouched but might be internal fault.
Here's my other possibly related issue.
If I run around with ECU box unclipped then the car runs fine. When I button down the box by the headlight I get canbus issues: Brake stop safely, transmission service, no speedo, no rev or temp gauge. Eventually no start.

I'm thinking the box is pinching wires or a connector is broken and to be honest I'm fearful of opening it up.
Matt

Power it up, its probably fine.
Sounds like corrosion on the ecm terminal.