[LegalM340i]

This post saved me $3k. Thank you all! Having the tune didn’t mess with anything!

However now I’m trying to figure out how to deal with the 2020 B58 oil pump issue.

[Rafzan]

Originally Posted by LegalM340i

This post saved me $3k. Thank you all! Having the tune didn’t mess with anything!

However now I’m trying to figure out how to deal with the 2020 B58 oil pump issue.

I’m getting this same issue fixed now and the dealership keeps giving me different dates it’ll be ready. How long did the repair take for yours?

[x3Prancer]

Do all X3 30i's have a HMM? Or were these on the later model years, replacing the original thermostat design? How do I know if my 2019 has the HMM or thermostat?

[Wgosma]

Originally Posted by x3Prancer

Do all X3 30i's have a HMM? Or were these on the later model years, replacing the original thermostat design? How do I know if my 2019 has the HMM or thermostat?

I’m pretty sure the module is used in all G01 cars- you can but your cars VIN into the Real OEM website and verify specific componentry.

[x3Prancer]

According to Real OEM, my 2019 X (6/2019) has this part number:
https://www.fcpeuro.com/products/bmw...er-11537644811

The 2020 BMW X3 30i has this part number:
https://www.fcpeuro.com/products/bmw...er-11538642560

Whats the difference?

[Mondomensch]

Didn’t they make a set of improvements to the B48/58 engine in the 2019-20 time frame? The TU engine versions are post update so I would think you are seeing HMM versions appropriate for the pre and post update engine versions.

[x3Prancer]

4811 is in the front of the engine:
https://www.realoem.com/bmw/enUS/sho...89#11537644811

2560 is on the side near the oil filter housing:
https://www.realoem.com/bmw/enUS/sho...53#11538642560

Which one is having the issues?

[x3Prancer]

I just called BMW, 11537644811 is an electronic thermostat as they called it,
11538642560 is a heat management module. Which one is giving the issue?

[Mondomensch]

Originally Posted by x3Prancer

Which one is giving the issue?

Who are you asking? Isn’t the problem on your car?

[x3Prancer]

Its not leaking yet....Im asking which part is having these issues

[Mondomensch]

There’s a good YouTube video by FCPEuro from last year that talks about the various common issues on recent B48/58 engines, including HMM, oil filter housing, etc.
FCPEuro B58/48 engine issues

[LegalM340i]

Originally Posted by Rafzan

I’m getting this same issue fixed now and the dealership keeps giving me different dates it’ll be ready. How long did the repair take for yours?

It was fairly quick! One week or less!

[Bill_G]

I am battling BMW NA now on this issue. Of course, the dealer immediately said it was not covered. I found this email string and did some research. My dealer estimated ~$5200. There is no publicly published “official failure rate percentage” from BMW for the heat management module (HMM). However, from service data, owner reports, and repair guidance, we can estimate how often they tend to fail and at what mileage.

Typical Failure Frequency

Many BMW technicians and owner reports indicate the heat management module often fails between ~80,000 and 120,000 miles.

Some failures occur much earlier (50k–70k miles), especially on engines such as B46, B48, and B58 used in modern BMWs.


From independent repair shops and forums, the approximate failure incidence is often estimated around 10–20% by 100k miles for affected engines.
(This is inferred from service experience and warranty claims, not an official BMW statistic.)

Why They Fail
Common failure modes include:
Internal rotary valve sticking
The valve can get stuck in a warm-up position, restricting coolant flow and causing overheating.
Coolant leaks
Plastic housings and seals degrade from heat cycles.
Electrical actuator failure

The module contains electronics that control coolant flow and can fail due to heat and vibration.

Mechanical wear inside the module
Internal valve components and plastic interfaces wear over time.

Typical signs include:
Engine overheating or fluctuating temperature
Check-engine light with faults like 20F206, 20F220, or 20A704
Coolant leaks around the module
Reduced fuel efficiency due to incorrect engine temperature regulation

Labor: often 5–11 hours depending on engine layout

Typical total: $1,200 – $4,000 at dealerships.

The heat management module is not designed as a maintenance item, but in practice it behaves like a wear component in the cooling system, similar to BMW electric water pumps and thermostats.

I also found this- https://www.ncconsumer.org/news-arti...verlooked.html

And this Emission Related Warranty from the Code of Federal Regulation- https://www.ecfr.gov/current/title-4...ction-1037.120

In summary, from the CFR-The emission-related warranty also covers other added emission-related components to the extent they are included in your application for certification, and any other components whose failure would increase a vehicle's CO2 emissions.


I will follow up and let you know what BMW's decision is.

[Mondomensch]

I suspect any federal co 2 related limits are now gone, but if your car is sold/registered in a state where the CARB Calif emissions requirements applied, the HMM is considered part of the emissions system and warranted under the much longer emissions warranty.

Always good to get a copy of the various warranties for your specific car to find out the details and to have the written warranty section to show BMW.