Map Cooling????

[Unresolved]

Today my friend whos got a garage, was asked by "desperate* me to run a computer check on my car .. the only thing that popped up was - Error 139 Activation Map Cooling .. what the heck is that??? :confused does it have anything to do with the temp readings of the engine?

please help

[thejlevie]

That is saying that the DME controlled thermostat isn't working. And yes, if it fails the engine won't run at normal temperature. Your car doesn't have a conventional thermostat that's operated solely by coolant temp. Instead the operation of the thermostat is controlled by an electrical heater that the DME controls.

[crown14]

I posted almost the same exact thread within the last 2 weeks.

It dosent necessarily mean the electronic tstat is dead (mine certianly isnt) but that there was a fault detected somewhere in the system.


Fault code 139 Map Cooling, this fault code is stored if the Map cooling thermostat is faulty or the wiring from the engine control unit to the Map cooling thermostat is shorting to ground. The Map cooling thermostat is a electronically controlled thermostat. This type of thermostat is controlled via the DME control unit to progressively open or close depending on information received by the DME. If this fault code is present you must first change the Map Cooling thermostat and check the wiring to the control unit. The Map cooling thermostat is mounted in the same position as a standard type stat but is recognised by a large sensor on the top of it.

That means I ordered a thermostat. This wont help you much but my cost was $48.

[Unresolved]

ok .. so do i change the thermostat???

see the thing is, this problem appeared like a month back .. so i have changed the temp sensor .. i thought that was the problem .. but now, since it re-appeared again, im confused ..

[Unresolved]

aha! so thermostat it is then ... !!
thanks so much guys!!!

[Unresolved]

Now as we see, this thread was started by me a year back ..
Now i'm having the same problem .. the weirdest thing is that I have replaced the thermostat .. but i'm still having the same problem ..
Now I have a question .. why does my car usually does this funny idle thing when it gets really hot in the summer?
Is there a point i'm missing?
Recently, I have replaced spark plugs, cam shaft sensor and so on ..
When the car is on idle, RPM jumps up and down from 700 to 1,500 in 10 minute intervals .. and this started happening after i replaced the position cam shaft sensor, b4 replacing that, rpm would just drop (when the car is idle) and the car would shatter and jerk ..
Sometimes the engine stalls when I stop at a traffic light .. the only fault, which is registered is 139 activation map cooling .. can this cause all of the above I've mentioned?

[andrei09]

Quoted from bba-reman.com web site. Unfortunately I can't post link to see other BMW "bugs"


Thermostat Software and Oxygen Sensor/ Misfire Reprogramming
Model:
E38 – 740i/iL with M62/M62TU produced between April 1997 and August 1999
E39 – 540i/iL with M62/M62TU produced between April 1997 and August 1999
Complaint:
The check engine light is illuminated, and upon further investigation fault codes 10-02 sensor pre catalyst (Bank 1), 12-02 sensor post catalyst (Bank1), 19-02 sensor pre catalyst (Bank 2), 20-02 sensor post catalyst (Bank2), various misfire faults, 139 or 140 Activation Map Cooling may be stored in the Engine Control Module (ECM/DME) after a software error.
Remedy:
Check the DME programme number and reprogramme the DME with CD21 or higher if necessary.
If the fault code 139 or 140 has been stored in the DME ensure the thermostat wiring and thermostat are functioning correctly. Repair any faults before reprogramming the DME.

[kupplung]

Howdy ya'll, I'm working on a no-start, and I've got the 139 code, map cooling fault.

Does this fault normally lead to a no-start condition?

Car cranks, voltage is good (2ga jumper cables...). Fuel pressure is good at the rail. From my research, it sounds like a crank or cam shaft position sensor, but there are no error codes about this. Can those sensors fail without codes?

[Justin517]

I had this code and replacing the thermostat fixed it.

AS Far as i know having this code won't even throw a CEL, and it shouldn't cause a no start.

[thompsw]

I just started getting the equivalent code on my 2004 X5 and it does produce a Service Engine Soon.

I replaced the thermostat last year (stuck open) so I'm disappointed that this happened so soon. However, I did put 50,000 miles on the car in the interim !

[halojereme]

Sometimes the engine stalls when I stop at a traffic light .http://www.hgniw.info/11a.jpg

[ViolinARC]

Sometimes the engine stalls when I stop at a traffic light .http://www.hgniw.info/11a.jpg
Mine started doing this too and finally illuminated the SES. I have INPA error 115 HFM and 140 T-stat cooling {been replaced twice now). I've replaced the MAF today and cleared the error codes. Big test run tomorrow...

[ViolinARC]

Mine started doing this too and finally illuminated the SES. I have INPA error 115 HFM and 140 T-stat cooling {been replaced twice now). I've replaced the MAF today and cleared the error codes. Big test run tomorrow...
The car is running like new again so the stalling issue was definitely a failed MAF. :cool

[Silverlight]

The car is running like new again so the stalling issue was definitely a failed MAF. :cool

Did you try cleaning the old one before replacing?

[ViolinARC]

Did you try cleaning the old one before replacing?

Nope...as Randy has pointed out, the HFM5 doesn't actually have any exposed, cleanable parts. The cleaning method only applies to the older style MAF's but in my earlier ignorance, I posted a DIY on cleaning mine. It appeared to work at the time but now I think I just got lucky cause I did other performance maintenance at the same time.

I still have the original and have cleaned it a couple times but if I reinstall, the system spits out lean bank codes almost immediately. I'm still keeping this second replacement as a backup so I'll clean it, reinstall and see if the problem continues since I now have a properly operating MAF on hand...

[ninetyseven1]

Today my friend whos got a garage, was asked by "desperate* me to run a computer check on my car .. the only thing that popped up was - Error 139 Activation Map Cooling .. what the heck is that??? :confused does it have anything to do with the temp readings of the engine?

please help



Can I ask you if your map cooling also stopped working when you got this error? In other words, if you floor the gas pedal usually the temp should drop down to 80C. Does yours do this?

[Vytas]

Is there anyway I can code(adjust) the temperature that DME tries to hold as normal working temperature? Does that kind of variable exists at all? Because now the engine is always holding 99c(not more not less), with or without fan-clutch. It just uses more or less radiator potential by electronically controlling the flow via electronic thermostat. Looks like there is some kind of default DME likes to hold on, so it must be the place this variable is stored. Personaly I don't like such temperature and would like to keep it on 89-90c even if the high working temperatures is normal on M52TU,M54's... So anybody know how can i found and can i code the unit which is responsible for engine cooling?

[RocketSurgeon]

Is there anyway I can code(adjust) the temperature that DME tries to hold as normal working temperature? Does that kind of variable exists at all? Because now the engine is always holding 99c(not more not less), with or without fan-clutch. It just uses more or less radiator potential by electronically controlling the flow via electronic thermostat. Looks like there is some kind of default DME likes to hold on, so it must be the place this variable is stored. Personaly I don't like such temperature and would like to keep it on 89-90c even if the high working temperatures is normal on M52TU,M54's... So anybody know how can i found and can i code the unit which is responsible for engine cooling?

It can't be coded the way that you are thinking. You can fit a lower temperature thermostat, drill small holes in your thermostat, weaken your thermostat spring with a pencil torch, or build a small controller that can adjust the map cooling activation (very very involved). Lowering the temperature isn't all good though, engines are less efficient and take much more wear at lower temperatures. If you are really interested in the map cooling activation project, there's a massive thread on an X5 site, but it involves making a fairly advanced circuit board. You might ask DUDMD about that though, he writes some very nice tunes and he might have the capability of changing map cooling parameters. You might send him a pm or refer him to this thread, lots of people ask about that.

[s14b23]

It can't be coded the way that you are thinking. You can fit a lower temperature thermostat, drill small holes in your thermostat, weaken your thermostat spring with a pencil torch, or build a small controller that can adjust the map cooling activation (very very involved). Lowering the temperature isn't all good though, engines are less efficient and take much more wear at lower temperatures. If you are really interested in the map cooling activation project, there's a massive thread on an X5 site, but it involves making a fairly advanced circuit board. You might ask DUDMD about that though, he writes some very nice tunes and he might have the capability of changing map cooling parameters. You might send him a pm or refer him to this thread, lots of people ask about that.
Much easier to modify oem tstat like I did.
Keeps it cool 93-96 max
No cel

[s14b23]

Is there anyway I can code(adjust) the temperature that DME tries to hold as normal working temperature? Does that kind of variable exists at all? Because now the engine is always holding 99c(not more not less), with or without fan-clutch. It just uses more or less radiator potential by electronically controlling the flow via electronic thermostat. Looks like there is some kind of default DME likes to hold on, so it must be the place this variable is stored. Personaly I don't like such temperature and would like to keep it on 89-90c even if the high working temperatures is normal on M52TU,M54's... So anybody know how can i found and can i code the unit which is responsible for engine cooling?

Which tstat you have??
99 for M54 means you've got a leak
M54 with BEHR tstat (much better and cooler than Wahler): 93-96C max
M54 with Wahler keeps it at 97-99 and is very important it should cycle through 97-99 which means tstat is working correctly and no leaks.
Don't buy Wahler for m54.

I think I still have m54 tstat behr calibrated to open at 91-92

[Vytas]

Thank you for interesting information for adjusting. My engine is M52TU. So we are talking about 528i. And i don't know where can i get lower temp. tstat. I dont have any leaks, or any air inside. Head gasket is ok, no pressure to the system or water sucking inside. I have BEHR tstat. from ebay (link (http://www.ebay.com/itm/151119525402?_trksid=p2059210.m2749.l2648&ssPageName=STRK%3AMEBIDX%3AIT)), it works good already about the year. Before i bought it the temperature was 109c always. Now its 99c, everything in the cooling system is replaced. I tired of that fancluch always on at working temperature when driving in city, just wasted the money on that new clutch... Tried to drive few days without it was so much better for engine, less load on the belt, more power, better economy, and most important no noise. The aux. fan was dealing with the temperatures easily, when engaged drops the temperature from 99 to 94 immediately, then the tstat. brings it back to 99 again. I have also noticed that without fan clutch the lower hose is more warm because it uses more radiator potential. If i drive with clutch on, the lower hose is almost always cool. My temp. gauge is also slightly to the right from the middle but it something with electronic buffer i guess..
So it is definitely some thing is wrong with setting the default working temperature. If there is anyway you could provide more info or instructions with pics how you modified your thermostat to work on 94c it would be amazing. Maybe I could drive with the fan shut off finally...

- - - Updated - - -




I think I still have m54 tstat behr calibrated to open at 91-92

Do you have it for sale? One thing is to open at 91-92 another is to keep the engine on that range :/

[jstern]

I also have a 528, M52TU engine. I use a Wahler thermostat and monitoring engine coolant temp on test #7 on unlock OBC, the temp stays at 93C and cycles up to 96C and then back down to 93C on hotter days.

[s14b23]

I also have a 528, M52TU engine. I use a Wahler thermostat and monitoring engine coolant temp on test #7 on unlock OBC, the temp stays at 93C and cycles up to 96C and then back down to 93C on hotter days. This is a correct working cooling system here. Higher temps mean some issues with cooling system. Could be a leak or even bad rad cap or heater core or even head gasket leak

[Poolman]

OEM Stat Is Wahler--Never Again will ever use the Behr,,the engine never got above 84C in cold weather,,I thought I had a vacuum leak somewhere from the way my car was using petro...Whaler installed and the temp was right where it was supposed to be afterwards...

[s14b23]

OEM Stat Is Wahler--Never Again will ever use the Behr,,the engine never got above 84C in cold weather,,I thought I had a vacuum leak somewhere from the way my car was using petro...Whaler installed and the temp was right where it was supposed to be afterwards... Can't be right, may be you installed defective tstat half opened. I installed behr tstat about 15 times and always 93-96 With Wahler it gets 97-98 Also if you open behr you will understand why it's more expensive.

Simply look at behr tstat element quality and how heater installed and then look at Wahler and ask yourself a question why so many failures with Wahler heating element leaking, creating air buble overheating engine.

[Poolman]

I have only replaced 3 of them. Once with the Behr and went around chasing my tail trying to find my fuel problem, then later caught the culprit. Afterwards I have used 2 of the Wahler stats and never had a problem with either of them,,both holding right at 94C from checking the OBC test 7. Almost 300k miles on the car now and never had an inkling (knock on wood) from an over heat.

[s14b23]

I have only replaced 3 of them. Once with the Behr and went around chasing my tail trying to find my fuel problem, then later caught the culprit. Afterwards I have used 2 of the Wahler stats and never had a problem with either of them,,both holding right at 94C from checking the OBC test 7. Almost 300k miles on the car now and never had an inkling (knock on wood) from an over heat. Do you know DME opens fup tstat when driving at 60-70mph?? So when driving it's ok to have 89c Test when idling without heater. Behr is 94-96 very steady, plus upper limit can be calibrated unlike Wahler. If you look at Wahler you can see it's much cheaper than behr. Behr has solid metal wax motor design and similar to V8 design unlike plastic behr. Don't forget 90% cooling failures are bc of high pressure and the higher the temp the more likely you'll get famous radiator cracks and cooling tank cracks along with other leaks. I always install lower pressure rad caps and in one car cooling system lasted 150kmls since last colony system overhaul. Pretty impressive. Look most of the Wahler failures are due to rubber getting old and tstat plate isn't sealed well, Behr has metal plate without any cheapy rubber, which shrinks with age just like any rubber part and leaks coolant.
Let's put it this way:
How many behr failures vs Wahler on m54??
Wahler fails every 50-70k due to that plate not sealing. Behr only fails if bearing goes bad

[ninetyseven1]

All you have to do is use a lower temperature thermostat and an electric fan. The E31 840Ci uses a cooler 95C thermostat that is a direct bolt in. There is also a guy on ebay selling 80,87C thermostats for 540i's. Then lastly you will need to connect the heater element wires to a 12 ohm 100watt resistor to avoid any codes being set.

[YAH]

Function of the characteristic map thermostat
The characteristic map thermostat is tuned such that it opens at a coolant temperature at the thermostat of 103oC from the engine inlet without intervention of the integrated heating facility. Due to the coolant being heated in the engine, the temperature at the engine outlet (place of installation for the coolant temperature sensor for DME and instrument cluster display) is approx. 110o C at this point in operation. On reaching this engine operating temperature the characteristic map thermostat begins to open without control intervention.
In the event of control intervention by the DME control unit, power (12 V) is applied to the heating element integrated in the thermostat. Heating the expansion element means that the thermostat opens at lower coolant temperatures (thermostat control range: approx. 80oC - 103oC).

[ninetyseven1]

no, the map thermostat sucks. Everyone knows that. Most of the time you are not at the hot 103C, it keeps you at 105-108 on most 540is which is way too hot. The way to go is the 95C thermostat and an electric fan. There are may other benefits to this including , no exploding fan, a much cooler running engine and increased water pump life.

[Danny Wolfe]

Hello Jim: I am also located in Huntsville, AL. I would love to have you look at my car if you would be willing to do so. I have a 2001 740i. I have a few issues to resolve in my cars...Please email me at dannywolfe@knology.net for info on how to contact you to set something up. I do have some questions for you...thanks very much!