Thermostat Soft-Failed at 85k - Do I need to replace other parts?

[RocketyMan]

Originally Posted by oldskewel

I'd be more concerned about the hoses (good point about the plastic hose ends being a concern as well as the rubber - on my 3.0i's upper radiator hose, it was the plastic end near the radiator that failed first, at around 180k miles) than the thermostat. And it sounds like if anything, the thermostat failure mode is that it sticks open, which is not going to blow anything up.

But on the thermostat, does anyone have a good number on what the resistance of the heating element should be? My 2001 3.0i has a 50k-mile old, dealer-installed Genuine BMW thermostat, and I don't have an OBD code or engine light, but ...

Recently I've been getting the following code on my Foxwell:
1-DME, 7B DME: Activation, map cooling
Looking that up gives reports of it being the thermostat heating element. I measured the resistance of my heating element as 3.7 Ohms, which seems in the right ballpark, but am wondering if it is in spec.

OP, related to this, have you measured your thermostat heater resistance? Scanner info (note that I have no issues I can see other than that code which only appears in the Foxwell BMW diagnostics)? Have you tried leaving the connector unplugged to see if your engine runs hotter? Suggested for debugging, not as the solution.

I have the same fault code in mine! This is rom the STANT branded thermostat housing that was made in germany.

A new heater element should be around 15 to 16 ohms. So 3.7 ohms would def be considered "shorted."

[oldskewel]

Originally Posted by RocketyMan

I have the same fault code in mine! This is rom the STANT branded thermostat housing that was made in germany.

A new heater element should be around 15 to 16 ohms. So 3.7 ohms would def be considered "shorted."

The new one just arrived. I could not get a Wahler in time (the one I just took out is a Genuine BMW, made by Wahler), so got a Mahle. Resistance measures at 15.8 Ohms.

I now fully expect this will solve my DME error code but, as listed in the other thread, I seem to have other problems right now.

[X5only]

Don't forget to replace the dual temperature switch 13621703993 and its cheap. I replaced both the thermostat and dual coolant temp sensor. I kept getting DME error 2EF4/82 - Engine characteristic map thermostat, Mechanics. Dual temp sensor was dark on one side and sparkling clean on the other - looked strange and I don't think it was delivering the correct data.

[puddinboo]

When my thermostat was going ,I replaced it along with the water pump while I was in there. Easy job.

Sent from my SM-G781W using Xoutpost.com mobile app

[oldskewel]

Originally Posted by X5only

Don't forget to replace the dual temperature switch 13621703993 and its cheap. I replaced both the thermostat and dual coolant temp sensor. I kept getting DME error 2EF4/82 - Engine characteristic map thermostat, Mechanics. Dual temp sensor was dark on one side and sparkling clean on the other - looked strange and I don't think it was delivering the correct data.

https://www.realoem.com/bmw/enUS/sho...69#13621703993



I don't have any known errors for that part, and plan to currently focus on the known faults. Also, that part (am familiar with it, but thought it was the sensor [not switch, let alone double switch, as it is called] used by the instrument panel temp gauge) seems to be at the back end of the head, under the intake manifold, so it's not like I'm "in there" ... yet

Any info on accuracy of it being called a switch vs. double switch (and if so, the temperatures) vs. sensor. I see real OEM calls it a double switch, and somewhere referred to it having a four wire connector, but then it seems to also be common knowledge that it is the CH temp sensor. ???

[X5only]

My bad, I was assuming it's the V8 engine, which has the sensor on the water pump.

[RocketyMan]

Originally Posted by oldskewel

The new one just arrived. I could not get a Wahler in time (the one I just took out is a Genuine BMW, made by Wahler), so got a Mahle. Resistance measures at 15.8 Ohms.

I now fully expect this will solve my DME error code but, as listed in the other thread, I seem to have other problems right now.

I think it's interesting how your thermostat heater failed the same way as mine. I still haven't replaced mine yet even tho I have a replacement part. ERgh!

[Len]

Finally ordered a tstat and coolant from FCP and just got the package. It’s a BorgWarner which was listed as OE. Will update once I’ve installed it. Hopefully that’s all it is. I’ve had the connector unplugged for a while and originally thought it might’ve made a difference but now it seems to be the same.