DCT Transmission Temperature Warning???

[eocrm3]

I was driving home from work today, about 5 miles into the drive I stop at a red light....all of a sudden a warning message pops up on iDrive screen that stated to "avoid stop and go driving" .......the message also stated something about maintaining “continuous driving”.

During the warning the RPM bumped up to 1K RPM…the warning lasted about 10 seconds and as soon as the message disappeared off the screen the RPMs dropped to normal again.

I immediately did a systems check through iDrive and All Systems Check came back “Ok”.

A little background on my car:
2010 DCT
58K miles

All stock, no track use. Daily driver, daily usage is about 25 miles.
No prior engine or transmission issues.

I live in South Texas so we’re currently averaging around 97 degrees during the day. When this happened I had just exited freeway, non-aggressive driving right before message…..basically normal driving.

I called my SA at BMW Dealership and he said he would check with the shop foreman in the morning as he had never heard of this type of warning on m3s before. He told me just to monitor if the message reappears.

Any idea what the issue could be? I’m now paranoid that there might be an impending catastrophic DCT issue awaiting my car!

[FormulaMMM]

How was your oil temp reading? Could just be an electronic gremlin if it's not recurring and you're not sensing anything is off.

[eocrm3]

Oil temperature reading was right at 210.

[lve2xlr8]

You weren't holding the car with the clutches on a hill, right? Instead of the brake

[eocrm3]

No, car was on level road/street.....I had been stopped at a light for about 10 seconds before warning came on.

Also, I always drive on auto mode......with 3 m bars set for normal, daily driving.

[tinman831]

You may want to check for tranny leaks in case you're low on fluid.

[eocrm3]

I tried to get a good look at the car's undercarriage as best as I could without a lift, but don't see any signs of a leak, nor are there any oil stains underneath the car in my garage.

If the car would happen to be leaking or lacking DCT fluid, would there be a low fluid level indicator message? The same type of message that appears when the m3 prompts to add engine oil due to low level?

[SenorFunkyPants]

The underneath of the DCT is covered by a panel which has drain holes...if you were losing enough fluid to cause an overheat its likely you would see signs on your garage floor.
Could be a faulty temp sensor in the DCT.
There is also a preheat system that directs the DCT fluid through an (engine coolant) heat exchanger to reduce the time it takes to reach normal operating temp - a fault here (some sort of sticking thermostat perhaps) might cause an overheat.
You know of course only the dealer can figure it out but it should be some reassurance that the DCT has proven to be incredibly reliable.

[Edward]

This happened to me yesterday in murderous rage inducing bh -> downtown la traffic. I had spent about 40 mins in complete stop and go traffic in 79 degree weather. Car was running AC at two clicks above off position and DCT was set at D3 auto shifting mode, no power button on. I hit every single light possible and my car was getting virtually zero air flow across any heat exchanger panels.

Msg popped up and then disappeared. Car worked perfectly fine anyway.

I hate everyone that was on the road yesterday afternoon. Also, fuck this car for having insufficient transmission cooling. You should be able to idle for an hour in Dubai heat without the transmission freaking out.

I think that I'll avoid using bs driving modes like auto shifting below D4. I feel as if the overly eager to upshift weak driving modes perform too many unnecessary shifts. aka, shifting to a higher gear at sub 2500 rpm.

My guess is that the constant gear changes create more heat than hold gears a bit more or saving a couple shifts.

[dtla1]

Originally Posted by SenorFunkyPants

Could be a faulty temp sensor in the DCT.

Has anyone ever had this issue and been able to actually resolve it?

I've had this intermittently for 4-ish years, and it's annoying as hell when it happens because it's completely random, and just ruins all driving experience. The car holds revs to like 5k rpm when just trying to drive on a city street, and then hesitate, and then force into the next gear.

For me, it's lasted 5-15 seconds then gone away, or will last 5-15 seconds, go away and come back a few times, or who knows.

I've done fluid and filter replacement, I've had clutches replaced, I've had another shop check my fluid level afterwards.
The best I've been able to get is one shop that was able to pull an electrical wiring/sensor issue fault code, but they weren't really 100% sure, and couldn't say if they've seen it before. It sounded like the fix would be to replace the temp sensor, whether there was an actual electrical fault or maybe just a dirty sensor due to it being a combo sensor that also reads RPM using hall effect, so the magnet could be dirty or something, causing the temp to read the elevated temperatures of metal filings stuck on it, but that sounds less likely than a bad sensor.

The other issue is I wasn't clear whether they could go in and replace just the sensor, or as another shop mentioned, the sensor was integrated into the mechatronics, so the whole mechatronics would need to be replaced ($$$$$$$$$$$$$$)

Anybody ever go through this and resolve it?

[Helmsman]

Originally Posted by dtla1

Has anyone ever had this issue and been able to actually resolve it?

I've had this intermittently for 4-ish years, and it's annoying as hell when it happens because it's completely random, and just ruins all driving experience. The car holds revs to like 5k rpm when just trying to drive on a city street, and then hesitate, and then force into the next gear.

For me, it's lasted 5-15 seconds then gone away, or will last 5-15 seconds, go away and come back a few times, or who knows.

I've done fluid and filter replacement, I've had clutches replaced, I've had another shop check my fluid level afterwards.
The best I've been able to get is one shop that was able to pull an electrical wiring/sensor issue fault code, but they weren't really 100% sure, and couldn't say if they've seen it before. It sounded like the fix would be to replace the temp sensor, whether there was an actual electrical fault or maybe just a dirty sensor due to it being a combo sensor that also reads RPM using hall effect, so the magnet could be dirty or something, causing the temp to read the elevated temperatures of metal filings stuck on it, but that sounds less likely than a bad sensor.

The other issue is I wasn't clear whether they could go in and replace just the sensor, or as another shop mentioned, the sensor was integrated into the mechatronics, so the whole mechatronics would need to be replaced ($$$$$$$$$$$$$$)

Anybody ever go through this and resolve it?

Similar story here mate. Get the 5A53 trans overheat code intermittently over the last couple of years. At an indy a few month ago, changed fluid and oil Tsat/regulator. Code still there. BMW dealer couple of weeks ago, obviously came up with nothing, except for a diagnose bill... wanted them to do more investigations..."youre only a customer so p-off will you".

Trans replaced (after dealer f@ck up), 32k miles, works perfect except for the random code.
I have some verrry long shot theories about a failing aux pump that also provide coolant to the DCT oil/coolant heat exchanger which I get code on now and then. Will force down trans fluid to at least 100C in traffic. However got the overheat also at speed so...long shot.

Any aux pump codes in your end?

[DrFerry]

Check the DCT fluid level. Use manual mode in stop and go traffic, with a higher shift logic program - such as S4 - to avoid the DCT clutch slipping by the D (auto) mode logic program as it's trying to smooth out all of the shifts when in traffic. Consequently, perhaps the clutch pack overheated in an hour of stop and go South Texas city traffic.

[Helmsman]

Originally Posted by DrFerry

Check the DCT fluid level. Use manual mode in stop and go traffic, with a higher shift logic program - such as S4 - to avoid the DCT clutch slipping by the D (auto) mode logic program as it's trying to smooth out when in traffic. Consequently, perhaps the clutch pack overheated in an hour of stop and go Dubai city traffic.

Using S4 pretty much always, always foot on break when stop, yep trying to keep clutch slip in mind.
Wonder how long it takes to warm up the DCT fluid. I can get the friggin code already before engine oil is fully warmed up. Seems crazy that trans temp would be high already.

[dtla1]

Originally Posted by Helmsman

Using S4 pretty much always, always foot on break when stop, yep trying to keep clutch slip in mind.
Wonder how long it takes to warm up the DCT fluid. I can get the friggin code already before engine oil is fully warmed up. Seems crazy that trans temp would be high already.

Yeah another reason I lean toward sensor/electrical issue is that I've been able to watch the trans temp a couple times when the error comes up. One time I was literally idling in my garage and the temp shot up 30 degrees or so, then came back down. Another time I was at a red light and watched the temp as the light went on and off a few times, the temp stayed constant.

I don't think my car has any type of aux pump that routes coolant to the heat exchanger, or oil to the heat exchanger, I though it was all piggy backed on the water pump for the car and the regular oil pump in the trans, but I could be wrong.

And just to add a couple notes, like you, I've gotten the code/error at super random times after starting to drive. Could be right after I start the car and start leaving my place, could be during a 2 hour fun drive, could be during a 15 minute trip to the grocery store.

The only other long shot theories/clues I have is it seems to start up mostly (**mostly, but not always) after making my first stop, for example, I was driving up into the mountains, totally chill, everything good. I slowed down and took a right onto a different street, 20 feet later, error. The other long shot observation, is that sometimes it starts up, when going a little uphill.

[Helmsman]

Originally Posted by dtla1

Yeah another reason I lean toward sensor/electrical issue is that I've been able to watch the trans temp a couple times when the error comes up. One time I was literally idling in my garage and the temp shot up 30 degrees or so, then came back down. Another time I was at a red light and watched the temp as the light went on and off a few times, the temp stayed constant.

I don't think my car has any type of aux pump that routes coolant to the heat exchanger, or oil to the heat exchanger, I though it was all piggy backed on the water pump for the car and the regular oil pump in the trans, but I could be wrong.

And just to add a couple notes, like you, I've gotten the code/error at super random times after starting to drive. Could be right after I start the car and start leaving my place, could be during a 2 hour fun drive, could be during a 15 minute trip to the grocery store.

The only other long shot theories/clues I have is it seems to start up mostly (**mostly, but not always) after making my first stop, for example, I was driving up into the mountains, totally chill, everything good. I slowed down and took a right onto a different street, 20 feet later, error. The other long shot observation, is that sometimes it starts up, when going a little uphill.

Yep, we clearly have the same shit going. I've noticed the same behavour for instance driving for a short while, just to have engine temps up. Making a short stop and after start there is the code and limp mode. In the beginning I stopped the engine but now I only stop the car and drive off, code gone.

Yes there is a 2nd cooler (and fluid pre heater) check page 45: https://www.m3post.com/forums/attach...4&d=1317583307.

Btw, how do you read trans fluid temp? Only got Carly which I dont believe sort that.

Cheers

[Drv4fun]

Originally Posted by Helmsman

Yep, we clearly have the same shit going. I've noticed the same behavour for instance driving for a short while, just to have engine temps up. Making a short stop and after start there is the code and limp mode. In the beginning I stopped the engine but now I only stop the car and drive off, code gone.

Yes there is a 2nd cooler (and fluid pre heater) check page 45: https://www.m3post.com/forums/attach...4&d=1317583307.

Btw, how do you read trans fluid temp? Only got Carly which I dont believe sort that.

Cheers

helmsman,
What is the programming level of the car and dct module? I had some different things happening and dealer did some software upgrades and all went away. This was years ago.

[Helmsman]

Originally Posted by Drv4fun

helmsman,
What is the programming level of the car and dct module? I had some different things happening and dealer did some software upgrades and all went away. This was years ago.

Its been updated a couple of times, last time maybe 3-4y ago. Don't believe there has been a new sw version relevant to our modules since. Ypu know from which to what version you got done?

[dtla1]

Originally Posted by Helmsman

Yep, we clearly have the same shit going. I've noticed the same behavour for instance driving for a short while, just to have engine temps up. Making a short stop and after start there is the code and limp mode. In the beginning I stopped the engine but now I only stop the car and drive off, code gone.

Yes there is a 2nd cooler (and fluid pre heater) check page 45: https://www.m3post.com/forums/attach...4&d=1317583307.

Btw, how do you read trans fluid temp? Only got Carly which I dont believe sort that.

Cheers

Ahh yeah, I take back what I said earlier, I think I only have the Oil/air heat exchanger (135i) https://www.realoem.com/bmw/enUS/sho...diagId=17_0319

I was able to read the trans temp using MHD (the tuning app).
I'll also try to remember to find the print out of the exact codes the one shop was able to get for me, specific to that sensor error.

[Helmsman]

Originally Posted by dtla1

Ahh yeah, I take back what I said earlier, I think I only have the Oil/air heat exchanger (135i) https://www.realoem.com/bmw/enUS/sho...diagId=17_0319

I was able to read the trans temp using MHD (the tuning app).
I'll also try to remember to find the print out of the exact codes the one shop was able to get for me, specific to that sensor error.

Very interesting, and what are the temperatures when the box goes down??

[Pig Farmer]

I’m not sure that I have a solution to the overheating error, but I may be able to answer a couple questions that came up in this thread... the transmission heats up pretty quickly. It will reach 40c in a minute or two, 60c in about 5 minutes of normal driving, and 80-100c in 10 minutes of spirited driving. This is all based on having an aftermarket pan with an additional liter capacity and another 0.6 liters from performing the GTS overfill procedure. I have never received the error code, but you can read the temps with a Foxwell NT 510 code reader. Another thing that may be helpful is that you can reset the clutch adaptation with the Foxwell unit. This process resets the clutch engagement points to reduce slip. I do this every six months and it seems to make the transmission happy. Just thought I would share.

[Helmsman]

Originally Posted by Pig Farmer

I’m not sure that I have a solution to the overheating error, but I may be able to answer a couple questions that came up in this thread... the transmission heats up pretty quickly. It will reach 40c in a minute or two, 60c in about 5 minutes of normal driving, and 80-100c in 10 minutes of spirited driving. This is all based on having an aftermarket pan with an additional liter capacity and another 0.6 liters from performing the GTS overfill procedure. I have never received the error code, but you can read the temps with a Foxwell NT 510 code reader. Another thing that may be helpful is that you can reset the clutch adaptation with the Foxwell unit. This process resets the clutch engagement points to reduce slip. I do this every six months and it seems to make the transmission happy. Just thought I would share.

Many thanks Farmer! Believe this is the first I ever seen reg DCT temps. Jeez, where does the heat come from?? Maybe I need one of those Foxwells, seem to be capable. As clearly a temp sensor signal available, shame Carly doesn't pull it.

And what temps would you say are high for the DCT fluid?

Ps. Hmm...wonder why there is a pre heater for the fluid when it comes up to temp that crazy fast? Weird, friction must be massive.

[BLuRRYM3]

I had the same thing happen to me. Last week I did the fluid, filter, new pan, etc. Also did the DCT software update and adaptation, which removed my Dinan tune. I was reading on bimmerworld that sometimes the DCT thermostat is the culprit. Since it was a cheap part around $100, decided might as well change that out too since it's fairly easy to swap out.

So far so good. Before I couldn't do the normal weekly three grocery store run without getting an overheat warning.

I have a thread where I'm providing updates:
https://www.m3post.com/forums/showthread.php?t=1817337