Hello all! I hope everybody had a great holiday season. It's been a cold winter, but now the weather will soon start to warm up again. For others out there whom are still affected by the HCU temperature sensor problem that we've all faced, the problem will simply repeat itself, unless we take further action soon. I now come to you asking for your assistance in the "next step". As you remember, we all spent about six months this past summer figuring out why our E46 M3 SMG's were randomly throwing on the Transmission Check light and randomly cycling into neutral for aruond 6-15 seconds, displaying a constant "0" during an up or downshift in hot and/or humid weather. We determined after plenty of research and physically removing the SMG's Hydraulic Control Unit(HCU), and comparing hard-to-find blueprints of the unit what the malfunction was. The problem was the HCU's Hydraulic Fluid Temperature sensor, which would go bad due to a thin-layered resistor inside the sensor that would microscopically bend and contract over time in avid heat/humidity situations, and send false data to the car's Transmission Control Unit, giving it the illusion that the HCU was overheating and needed to be shut down. To this day, I am still puzzled as to why BMW would program the control module to do such a thing, knowing it would temporarily mame the car's ability to accelerate and/or maintain speed, and thus endanger it's occupants and the safety of other motorists around it. We have enough evidence, diagnostic data, and knowledge to move forward with permanantly resolving our issue through BMW, themselves. As you already know, many people have been forced to purchase and install new HCUs, totalling close to $3,000 after installation. I don't think BMW will have a problem recalling a $20-sensor in the favor of keeping their product's occupants alive and well. After thurough research, the recalling processing period proves to be in the viscinity of three to nine months, on normal circumstances. As a very very loyal and active BMW enthusiast, BMW racing team owner, and private BMW Club Chapter President, it is only a shame in my opinion that this kind of action had to be taken directly by the company's very own customers, rather than the company, itself. I am asking in advance for your signature of approval in a letter I will write to BMW of North America, asking for a product recall of the Bosch Temperature Sensor in the E46 M3's Hydraulic Control Unit. We can fall back on the fact that this problem is potentially dangerous and remotely deadly, depending on a vast number of circumstances. Please let me know if you agree and accept all of the above. Thank you for your time, and good luck cruising in your SMG's this summer!
Sign Me Up After getting the shaft and the run around regarding the eventual bearing recall on my 2003 M3 that resulted in total engine replacement. We need to start now before this becomes an equally frustrating problem. Sandy
Many of you have sent me PMs stating that you agree. Because I will soon be receiving numerous signatures of consent, please PM me and state your signature of consent in the following format: EXAMPLE: Darren Andre Reston, Virginia 2002 E46 M3 Coupe I consent. Meagen Shaufrill Potomac, Maryland 2005 E46 M3 Convertible I consent. Mitch Caulfield Los Angeles, California 2003 E46 M3 Coupe I consent. etc, etc. Thank you to all affected by this problem for your agreement to this issue. Hopefully, it'll be completely taken care of by early 2010.
Issue Resolved. Good news! As of a phone call I made to the Executive Division of BMW N.A. this morning, this thread is now actively being monitored by BMW, themselves. They are submitting the problem to the appropriate department(s) as I am typing this. I also notified them of the PM's also stating signatures of consent. Please continue to give me your consent and thank you again to everyone for your voice as the permanant fix for this issue is finally, officially under way!
I personally have not had any issues to date, but if there is a known problem it would certainly be preferable to have BMW acknowledge it and give us a clear path for repair should it be needed. Thanks for heading that.
Can't consent to a letter that doesn't exist Darren, I appreciate what you're trying to do, but I can't consent to a letter I haven't seen. It could potentially relieve me of the ability to go after other fixes, especially if there was a problem that seemed like a temp sensor but was not. There's no way to know without seeing what you intend to send. Please post that which you're asking us to consent. I think collecting SMG problems could be a powerful thing; I'm not convinced there are that many temperature sensor problems. I'd have to see pics of the sensor you cut apart compared to a new sensor cut apart to even be convinced that your description of the failure is correct. A more scientific method would be to test a suspected sensor by controlled heating and taking resistive measurements across a temperature range, and getting the same information for that sensor from Bosch. Regards, ADS
E46 M3 SMG malfunction I consent. I have found that my SMG transmission fails to engage properly at times. Eventually it will, but it feels odd when attempting to do so.
I Consent. Hello all, I am having this exact same problem and have exhausted my research so I finally took my car to the dealer and let them have it knowing that they're gonna start replacing everything until they think the problem has been fixed. My car has been at the dealer for over 4 days now and they "think" that it's the entire SMG hydraulic unit. I hestitated to let them proceed with a $3,200 job and not knowing for sure what the root cause is. My last research on this let me to this posting, which gave a an abundant of confident that you guys may have found the root cause to this famouse problem. I have sent an email to the dealer service advisor with all the research information I had including this thread and will hope that they will try looking at the SMG hydraulic fluid temperature sensor. The symptom I am having is that during hot weather, the SMG yellow gear warning light would come on almost every day, but only on a rare occasion that it would pop out of gear and into neutral by itself for around 10 seconds and will then re-engaged. I had sent this email to the dealer earlier today and would much appreciate it if anyone can share any more information on this issue. Thanks! Duc Tran Portland, OR.
SMG Problems I Consent All, I too am having the same problem where the indicator light would pop on randomly then after turning the car off, it would disappear. I took the car down to the local independent BMW repair shop and they noted BMW Service Campaing Bulletin SI B23 01 04 (Nov 2004) which was never done on my car. I called the local BMW dealer and they said BMW would not cover this fix so I had the independent shop do this just in case that was the problem. Unfortunately not so now they are diagnosing the problem. My only gripe is that this car only has 49K on it...you'd think the tranmission wouldn't have problems this early on (car is always garaged and only used on weekends). Chris Danville, CA 2003 M3
