DME failure :( - Page 2 - BMW 3-Series (E90 E92) Forum

4DRSpeed · 11-19-2012, 09:23 PM

Well picked up my car in ATL Saturday and brought her back to Knoxville. I shipped the DME off to have it rebuilt by autoecu. 5yr warranty on it.

ajm8127 · 11-19-2012, 09:39 PM

Quote:

Originally Posted by themyst

Soldering on a diode is no more difficult than modding a JB4 board for whatever reason. If theres interest maybe ill start a service for that like onebadmofo does for coding.

It is not quite that easy. The MOSFETs that seem to go bad in DME are surface mount parts not through hole parts like the power resistor mod in the JB4. They can be challenging to hand solder because the package is specifically designed to shed heat. It can be made more difficult if there are full power and ground planes inside the circuit board as is common in multi-layer high density digital boards. It can be further complicated if you apply too much heat and burn the glue used to adhere the copper foil to the fiberglass substrate. This can result in "lifting" pads off of the substrate.

It is typical to use a board pre-heater to help warm the board up before applying the heat directly to the part to melt the solder, specifically with large parts like high power surface mount MOSFETs Hot air guns are also common in surface mount soldering. These are not the same as the ones you buy at the hardware store to strip paint. The temperature is precisely regulated and the air flow volume is considerably less than paint stripping models.

Considering the high price associated with replacing the DME, ensure you know what you are doing before you attempt to replace parts on the DME PCB.

I'm not trying to pick a fight, but I have a good bit of experience in this area, and I know just how much of a pain it can be. Without the right equipment and experience, you can have a costly mistake on you hands. However, using care and the right tools, surface mount soldering high power packages by hand is doable.

themyst · 11-20-2012, 09:17 AM

Quote:

Originally Posted by ajm8127

It is not quite that easy. The MOSFETs that seem to go bad in DME are surface mount parts not through hole parts like the power resistor mod in the JB4. They can be challenging to hand solder because the package is specifically designed to shed heat. It can be made more difficult if there are full power and ground planes inside the circuit board as is common in multi-layer high density digital boards. It can be further complicated if you apply too much heat and burn the glue used to adhere the copper foil to the fiberglass substrate. This can result in "lifting" pads off of the substrate.

It is typical to use a board pre-heater to help warm the board up before applying the heat directly to the part to melt the solder, specifically with large parts like high power surface mount MOSFETs Hot air guns are also common in surface mount soldering. These are not the same as the ones you buy at the hardware store to strip paint. The temperature is precisely regulated and the air flow volume is considerably less than paint stripping models.

Considering the high price associated with replacing the DME, ensure you know what you are doing before you attempt to replace parts on the DME PCB.

I'm not trying to pick a fight, but I have a good bit of experience in this area, and I know just how much of a pain it can be. Without the right equipment and experience, you can have a costly mistake on you hands. However, using care and the right tools, surface mount soldering high power packages by hand is doable.

Well aware of what needs to be done. No hand job will be nearly as pretty as it came from the assembly but the point is it can be done, just much more time-consuming than something like a JB4.

Other option is to buy a new DME and have it recoded, pay hundreds to fix it.

4DRSpeed · 11-20-2012, 09:19 AM

Quote:

Originally Posted by themyst

Other option is to buy a new DME and have it recoded, pay hundreds to fix it.

Or send it to www.autoecu.com for $400 with a 5yr warranty

ajm8127 · 11-20-2012, 11:23 AM

Quote:

Originally Posted by themyst

Well aware of what needs to be done. No hand job will be nearly as pretty as it came from the assembly but the point is it can be done, just much more time-consuming than something like a JB4.

Other option is to buy a new DME and have it recoded, pay hundreds to fix it.

Not disputing it can be done, just pointing out it is much different than the JB4 mod. JB4 mod is beginner level soldering. Changing D2-PAK FETs on a multilayer boards is more advanced and should be left to someone with the skill, experience, and tools to do the job. Your post at 6:12pm on 11/19/12 makes it seem as if the difficulty level is similar.

I just don't want someone without the proper experience, etc. to read this and think because they tackled the JB4 resistor mod, they can open up their DME and start changing FETs.

tmo335tt · 11-20-2012, 11:34 AM

The injector MOSFETs on this board are not very difficult to solder..I did it and replaced two on my board with no problems and it took me no longer than 30 min..it took me longer to determine which ones were bad. If you have ever soldered on an RC car or the like then you can handle it. Plus if your thinking about buying a new DME then you have nothing to lose by trying this first. I was lucky and fixed mine for free by bumming parts out of another members failed DME.

themyst · 11-23-2012, 09:53 PM

Quote:

Originally Posted by 4DRSpeed

Or send it to www.autoecu.com for $400 with a 5yr warranty

Not a bad idea for someone who can't stomach a DIY repair.

R 4 5 T 4 M 4 N · 12-01-2012, 10:55 PM

Quote:

Originally Posted by 4DRSpeed

Or send it to www.autoecu.com for $400 with a 5yr warranty

Whats the turn around time? My DME failed tonight and I would like to send it off to these guys.

4DRSpeed · 12-01-2012, 11:08 PM

Not worth it. They told me they didn't find anything wrong with it. I was hoping for a 5yr warranty, but I'm just gonna repair it myself now.

cn555ic · 12-02-2012, 07:47 PM

Quote:

Originally Posted by 4DRSpeed

Not worth it. They told me they didn't find anything wrong with it. I was hoping for a 5yr warranty, but I'm just gonna repair it myself now.

If you repair it yourself, make sure you get some extra parts thats needed because you can make a nice chump change repairing members on this forum...I would gladly pay you 200 bucks to get it repaired if mine was fried...

4DRSpeed · 12-03-2012, 11:47 PM

Tested the mosfets today. Injector #3 mosfet was bad on mine. I don't know how autoecu couldn't figure that out. Tomorrow install a new one and hope for the best.

R 4 5 T 4 M 4 N · 12-04-2012, 06:32 PM

1 and 2 are bad on mine.

4DRSpeed · 12-05-2012, 09:16 AM

Good luck R45.

I don't have good news for me. I'm not sure if I can blame autoecu or not. But a friend of mine came in and we took Injector #3 mosfet off and solder in a new one. Put my DME back in the car and it is not communicating to the car at all.

I'm 99% positive what we did, is not causing the communication issue. If we did do anything wrong bank 1 would still be down, not a power/communication issue. I'm not sure what autoecu did they just told me they didn't find anything and put some grease around the edges of the board.

But when I pulled the car onto the lift and pulled the DME out it was getting communication to the car. We tested everything and determined the DME relay was not waking up. Even when we forced it to the car was still not communicating to the DME. Luckily we had a 07 335i in the shop for service so I swapped DMEs to see if it would communicate and sure enough it did.

So I called the dealer and ordered a reman DME last night. I get a call this morning and was told BMW does NOT REMAN 07 DMEs. New ones are only available.

R 4 5 T 4 M 4 N · 12-05-2012, 07:05 PM

Replaced both of mine, the ecu error is gone, now I am getting 2e31 error (injection valve cylinder 1 input signal). I pulled all the connectors from injector 2 and blew them out, error still occurring. Not sure if that means its a bad injector as the connections seem fine.

R 4 5 T 4 M 4 N · 12-07-2012, 03:04 PM

Got my car back up and running, it was a bad connection on the harness that was causing the 2e31 error. My repair of the ECU was successful, both Ignition 1 and 2 MOSFETS had to be replaced.

4DRSpeed · 12-07-2012, 03:06 PM

Good to hear man. Wish I never sent mine off to autoecu.com. Definitely don't recommend them at all.

GUCCI_GEVO · 12-07-2012, 04:41 PM

Quote:

Originally Posted by 4DRSpeed

Good to hear man. Wish I never sent mine off to autoecu.com. Definitely don't recommend them at all.

How much is a brand new DME from BMW mine went bad also :/

joec500 · 12-07-2012, 07:10 PM

Quote:

Originally Posted by GUCCI_GEVO

How much is a brand new DME from BMW mine went bad also :/

Around $1,000 with labor.

cn555ic · 12-07-2012, 07:12 PM

Quote:

Originally Posted by R 4 5 T 4 M 4 N

Got my car back up and running, it was a bad connection on the harness that was causing the 2e31 error. My repair of the ECU was successful, both Ignition 1 and 2 MOSFETS had to be replaced.

Will you offer a service to repair the dme since you already have experience with it. I would gladly pay for your services if mine ever goes bad!

R 4 5 T 4 M 4 N · 12-07-2012, 08:19 PM

My only fear is if someone sends one in, I replace the MOSFETs and it does not resolve their issue. I would have to offer the service with no guarantee that it would resolve their issue, I can only guarantee that the faulty MOSFETS are replaced.

GUCCI_GEVO · 12-07-2012, 08:41 PM

Quote:

Originally Posted by R 4 5 T 4 M 4 N

My only fear is if someone sends one in, I replace the MOSFETs and it does not resolve their issue. I would have to offer the service with no guarantee that it would resolve their issue, I can only guarantee that the faulty MOSFETS are replaced.

Where do you get the parts you used to fix the dme (MOSFETS)

R 4 5 T 4 M 4 N · 12-07-2012, 09:56 PM

Mouser

11-19-2012, 09:23 PM	#23
4DRSpeed TWNEGOS Drives: 07 335i 6spd White/Red Join Date: Oct 2011 Location: Knoxville, TN Posts: 91 iTrader: (0)	Well picked up my car in ATL Saturday and brought her back to Knoxville. I shipped the DME off to have it rebuilt by autoecu. 5yr warranty on it. __________________

12-01-2012, 11:08 PM	#31
4DRSpeed TWNEGOS Drives: 07 335i 6spd White/Red Join Date: Oct 2011 Location: Knoxville, TN Posts: 91 iTrader: (0)	Not worth it. They told me they didn't find anything wrong with it. I was hoping for a 5yr warranty, but I'm just gonna repair it myself now. __________________

12-03-2012, 11:47 PM	#33
4DRSpeed TWNEGOS Drives: 07 335i 6spd White/Red Join Date: Oct 2011 Location: Knoxville, TN Posts: 91 iTrader: (0)	Tested the mosfets today. Injector #3 mosfet was bad on mine. I don't know how autoecu couldn't figure that out. Tomorrow install a new one and hope for the best. __________________

12-05-2012, 09:16 AM	#35
4DRSpeed TWNEGOS Drives: 07 335i 6spd White/Red Join Date: Oct 2011 Location: Knoxville, TN Posts: 91 iTrader: (0)	Good luck R45. I don't have good news for me. I'm not sure if I can blame autoecu or not. But a friend of mine came in and we took Injector #3 mosfet off and solder in a new one. Put my DME back in the car and it is not communicating to the car at all. I'm 99% positive what we did, is not causing the communication issue. If we did do anything wrong bank 1 would still be down, not a power/communication issue. I'm not sure what autoecu did they just told me they didn't find anything and put some grease around the edges of the board. But when I pulled the car onto the lift and pulled the DME out it was getting communication to the car. We tested everything and determined the DME relay was not waking up. Even when we forced it to the car was still not communicating to the DME. Luckily we had a 07 335i in the shop for service so I swapped DMEs to see if it would communicate and sure enough it did. So I called the dealer and ordered a reman DME last night. I get a call this morning and was told BMW does NOT REMAN 07 DMEs. New ones are only available. __________________ Last edited by 4DRSpeed; 12-05-2012 at 09:41 AM.

12-07-2012, 03:06 PM	#38
4DRSpeed TWNEGOS Drives: 07 335i 6spd White/Red Join Date: Oct 2011 Location: Knoxville, TN Posts: 91 iTrader: (0)	Good to hear man. Wish I never sent mine off to autoecu.com. Definitely don't recommend them at all. __________________

11-20-2012, 11:34 AM	#28
tmo335tt Second Lieutenant Drives: E90 2008 335i Join Date: Apr 2011 Location: here Posts: 233 iTrader: (0)	The injector MOSFETs on this board are not very difficult to solder..I did it and replaced two on my board with no problems and it took me no longer than 30 min..it took me longer to determine which ones were bad. If you have ever soldered on an RC car or the like then you can handle it. Plus if your thinking about buying a new DME then you have nothing to lose by trying this first. I was lucky and fixed mine for free by bumming parts out of another members failed DME.

12-04-2012, 06:32 PM	#34
R 4 5 T 4 M 4 N I bleed alpine white. Drives: BMW Join Date: Jun 2009 Location: Miami Posts: 2,005 iTrader: (12)	1 and 2 are bad on mine.

12-05-2012, 07:05 PM	#36
R 4 5 T 4 M 4 N I bleed alpine white. Drives: BMW Join Date: Jun 2009 Location: Miami Posts: 2,005 iTrader: (12)	Replaced both of mine, the ecu error is gone, now I am getting 2e31 error (injection valve cylinder 1 input signal). I pulled all the connectors from injector 2 and blew them out, error still occurring. Not sure if that means its a bad injector as the connections seem fine.

12-07-2012, 03:04 PM	#37
R 4 5 T 4 M 4 N I bleed alpine white. Drives: BMW Join Date: Jun 2009 Location: Miami Posts: 2,005 iTrader: (12)	Got my car back up and running, it was a bad connection on the harness that was causing the 2e31 error. My repair of the ECU was successful, both Ignition 1 and 2 MOSFETS had to be replaced.

12-07-2012, 08:19 PM	#42
R 4 5 T 4 M 4 N I bleed alpine white. Drives: BMW Join Date: Jun 2009 Location: Miami Posts: 2,005 iTrader: (12)	My only fear is if someone sends one in, I replace the MOSFETs and it does not resolve their issue. I would have to offer the service with no guarantee that it would resolve their issue, I can only guarantee that the faulty MOSFETS are replaced.

12-07-2012, 09:56 PM	#44
R 4 5 T 4 M 4 N I bleed alpine white. Drives: BMW Join Date: Jun 2009 Location: Miami Posts: 2,005 iTrader: (12)	Mouser

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