Cooling Fan Fault

[bobschultz]

I took a reading at the connector and have 12 volts. So does this mean it's the motor or where does the resistor fit into this. I looked for the resistor based on the location shown in some other posts but it's not up front behind the grill. Also, what does this part do? The number is 64116917001 and it says it's a sensor for the temp and fan that's sits near the connector and mounted on the shroud. My pic was too large to attach.

Appreciate any advice.

[admranger]

There is a difference between a fusible link and a fuse. I'm quite aware of this.

Also, I know more about this circuit than I care to admit after a reverse polarity incident w/a new battery.

If the 50 amp fuse is still good (easy to tell, use your volt/ohm meter to ensure there is 12v to ground across both legs). Then unscrew the fuse panel from the fuse box (after disconnecting the battery). Behind the fuse panel there are little fusible links. They have a metal tab sticking out of each end and are flat and about 1/8 inch thick. See this thread and scroll down to post #14: Here's what I'm talking about...

OBTW: my red 50A fuse was fine. My fusible link. Not so much. Replaced it and all was well with the X5's fan again.

YMMV.

[bobschultz]

Amazing, a hidden fusible link. But if I have 12 volts to my connector to the aux fan, wouldn't this imply the fusible link is fine? I'll read over that thread you referenced now. Appreciate your help.

[admranger]

Originally Posted by bobschultz

Amazing, a hidden fusible link. But if I have 12 volts to my connector to the aux fan, wouldn't this imply the fusible link is fine? I'll read over that thread you referenced now. Appreciate your help.

Yes. If you have 12v at the fan connector, all this is interesting but irrelevant.

[bobschultz]

Read your missing link thread, what a hoot. Interesting they decided to put two fuses in line. Must be a hell of a motor. So r we concluding my issue is the fan? Would the resister have any impact? I'll put power to the fan and try this next when I return from a wine drinking tour in north Georgia. Driving the Porsche instead.

[upallnight]

The fan needs a pulse width modulated signal (skinny wire on the connector) to command the fan to turn on. You can turn on the fan through software such as BMW Scanner 1.4 or INPA. Since you measured the connector and have 12 volts, that means you already have power and ground (two thick wires).

[upallnight]

Originally Posted by admranger

There is a difference between a fusible link and a fuse. I'm quite aware of this.

Also, I know more about this circuit than I care to admit after a reverse polarity incident w/a new battery.

If the 50 amp fuse is still good (easy to tell, use your volt/ohm meter to ensure there is 12v to ground across both legs). Then unscrew the fuse panel from the fuse box (after disconnecting the battery). Behind the fuse panel there are little fusible links. They have a metal tab sticking out of each end and are flat and about 1/8 inch thick. See this thread and scroll down to post #14: Here's what I'm talking about...

OBTW: my red 50A fuse was fine. My fusible link. Not so much. Replaced it and all was well with the X5's fan again.

YMMV.

Sounds more like a shunt circuit that blew when you installed or connected the battery in reverse polarity. Same thing happen to my neighbor when he went to install a new battery in his Rolls Royce. Replace the shunt device and the Rolls was running again.

[admranger]

Originally Posted by upallnight

Sounds more like a shunt circuit that blew when you installed or connected the battery in reverse polarity. Same thing happen to my neighbor when he went to install a new battery in his Rolls Royce. Replace the shunt device and the Rolls was running again.

I don't advise lifting the heavy X5 battery into position when you are tired. Those dang cables are right in the way and if one is not paying attention one can make contact with those cables. Not such a bad thing if you are putting the battery in with the terminals in their correct position. If one puts it in with the terminals reversed, well then things get exciting and expensive (both door controllers went poof too...).

Lots of learning of which circuit goes where and my Fluke got a heavy duty workout chasing voltage...

[bobschultz]

Originally Posted by upallnight

The fan needs a pulse width modulated signal (skinny wire on the connector) to command the fan to turn on. You can turn on the fan through software such as BMW Scanner 1.4 or INPA. Since you measured the connector and have 12 volts, that means you already have power and ground (two thick wires).

Did not think of it that way since I already have 12 volts at the connector. So I assume it's the fan motor or could there be an issue with not receiving the modulated pulse? Where is this generated from?

[upallnight]

Originally Posted by bobschultz

Did not think of it that way since I already have 12 volts at the connector. So I assume it's the fan motor or could there be an issue with not receiving the modulated pulse? Where is this generated from?

DME