code 7b?

2003 BMW 325I
179,000 MILES • 6 CYL • 2WD • AUTOMATIC
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BHAMDOC1973
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runs rough and had several misfire codes. deleted all code now still have code 7b related to thermostat. And now started it again and scanned and got these. Don't know what is going on.
Mar 15, 2024 at 8:51 AM
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JACOBANDNICKOLAS
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Hi,

Code 7 is related to the sensor on the radiator outlet (see pic below). Start by checking the wiring and connector on the sensor. Also, confirm there is 12v present at the sensor.

Let me know what you find.

Joe
Mar 15, 2024 at 7:19 PM
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BHAMDOC1973
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The outlet sensor harness looks fine, no broken wire or corrosion. But i found a big wire that is unplugged. Car has aftermarket headlights so i thought that might be it. But it's not. The radiator fan assembly is new and i see the plug connected on top so that is not it. The wire connector comes as a bundle which includes one's going to the fan and to the radiator sensor but has nowhere to go. I replaced these fans before on these cars and the big top plug that they connect to is the right one. Van you see if your diagram shows anything? The one you see next to it is the fan plug.
Apr 13, 2024 at 4:48 AM
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JACOBANDNICKOLAS
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Hi,

Are the three wires in the picture a solid blue, black, and brown? If that is the case, I'm having no luck. I've checked for a three pin connector with those wire colors and found nothing in the powertrain, radiator fan, headlamp, and heating an AC.

Confirm the colors for me. Also, take a test light and see if any of the connector pins have power.

Let me know what you find.

Joe
Apr 13, 2024 at 7:04 PM