Missing wire for coolant temperature sensor

2000 BMW 323

170,000 MILES • 2.5L • 6 CYL • 2WD • MANUAL

BLESSED.WITH.A.CURSE

MEMBER
1 POST

My E46 323i is overheating. I am pretty sure we narrowed it down to a coolant temperature sensor. I have one on the way but unfortunately then realized the wire that connects to the sensor is completely missing. I am not much of a mechanic and new to BMWs. I cannot even find a partial wire to find where it leads from. Is this something that can be fixed reasonably?

Sep 3, 2018 at 5:47 AM

PATENTED_REPAIR_PRO

✓ASE Certified Mechanic
1,853 POSTS

I can tell you it is two wires, a gray/brown and a brown/red wire. Both wires come from the Digital Motor Electronics (DME) Control Unit, located left rear of engine compartment. Here is what the connector to the ECT looks like, too.

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Sep 3, 2018 at 9:33 AM

10KEVOO

MEMBER
4 POSTS

Hey, did you every figure out the problem with it my cars been Over heating I recently bought this about a month ago and I realized I’m missing my connector to the coolant temperature sensor I don’t know where it is my mechanic couldn’t find it and so my cars been overheating,

Dec 18, 2022 at 4:04 PM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

here is what the sensor wiring connector looks like:

https://www.google.com/search?q=2000+BMW+323+cooalnt+sensor+pig+tail&rlz=1C1CHBF_enUS1035US1035&oq=2000+BMW+323+cooalnt+sensor+pig+tail&aqs=chrome..69i57j33i10i160l2j33i10i299l2.6448j0j7&sourceid=chrome&ie=UTF-8

It will have a green/brown and Brown/red wires. Let me know what you find.

Dec 19, 2022 at 3:47 PM

10KEVOO

MEMBER
4 POSTS

Do you think I can just wire it with the other wires?

Dec 19, 2022 at 4:47 PM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

Do you have wires near the sensor that match the color? if so you can wire in the new connector.

Dec 20, 2022 at 10:54 AM

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