Repairing a 'fried' N54 MSD80 DME

glachhman · 03-22-2014, 03:58 PM

Just ordered 6 transistors from digikey after my dme failed this morning. Just diagnosed it to be cylinder 5 with multimeter. I've soldered many things in the past but I am a bit confused about the heat gun and surface mount. Can the job be accomplished using a soldering iron carefully?

Edit just ordered a hot air gun, wish me luck.

AWTT335i · 03-23-2014, 10:27 PM

Quote:

Originally Posted by glachhman

Just ordered 6 transistors from digikey after my dme failed this morning. Just diagnosed it to be cylinder 5 with multimeter. I've soldered many things in the past but I am a bit confused about the heat gun and surface mount. Can the job be accomplished using a soldering iron carefully?

Edit just ordered a hot air gun, wish me luck.

You'll be glad you ordered the hot air gun. The underside of the chip has a pretty large contact.

AWTT335i · 03-23-2014, 10:31 PM

Here's mine I did last week. Runs great now. Not sure if it's related, but I was getting very minor misfires the first few pulls when beating on the car before the MOSFET let go. Never any codes.

glachhman · 03-24-2014, 09:49 PM

Quote:

Originally Posted by AWTT335i

Here's mine I did last week. Runs great now. Not sure if it's related, but I was getting very minor misfires the first few pulls when beating on the car before the MOSFET let go. Never any codes.

I had the same issues as well! I would do maybe 5 or 6 3rd to 4th WOT pulls then somehow I'd start to misfire. Or I'd NLS from 3rd to 4th and misfire.

Morpheus · 03-24-2014, 10:13 PM

This should be a sticky

glachhman · 03-25-2014, 05:28 PM

Transistors coming tomorrow!

https://www.dropbox.com/s/fjhpcpkupu...2018.16.24.jpg

glachhman · 03-27-2014, 03:03 PM

Success! Worked for me. I was able to get my car home but looks like the DME took injector 3 with it.

AWTT335i · 03-27-2014, 09:59 PM

Quote:

Originally Posted by glachhman

Success! Worked for me. I was able to get my car home but looks like the DME took injector 3 with it.

Ouch. Mine took out cyl 1 coil.

R1000K3 · 03-28-2014, 02:09 PM

It is quite risky to remove and mount surface mounted components in case the necessary tools and skills are not there. Especially large components like this where a lot of heat needs to be applied.

An optional method is to cut the leads and leave the broken transistors on the board. Then put new transistors on a heat sink and connect them to the board by wires if the component wires needs to be extended. That would minimize the risk for secondary board failure. I dont know how this board i designed but usually they are multi-layers with invisible cross bondings between layers. If a bonding is damaged it is only to trash the complete DME

glachhman · 03-28-2014, 04:17 PM

Quote:

Originally Posted by AWTT335i

Ouch. Mine took out cyl 1 coil.

Yep turns out it was two coilpacks not an injector!

woot

Ingeniator · 04-16-2014, 05:50 PM

Bump for sticky

waikiki35 · 04-16-2014, 09:13 PM

hello,
I have a bad MOFSET for injector 1... How do I desolder the old one and solder the new one? Is it that complicated?
If it is is there a place I can take it to to get it done?
Thanks

MikeE90NC · 06-02-2014, 09:46 AM

I tried ordering part IRF644B (correct ?) from digi-key and they are showing none in stock!? Is there another place to buy them????

AWTT335i · 06-02-2014, 11:53 AM

Quote:

Originally Posted by MikeE90NC

I tried ordering part IRF644B (correct ?) from digi-key and they are showing none in stock!? Is there another place to buy them????

Mouser has 1,322 in stock.

http://www.mouser.com/Search/Product...844-IRF644SPBF

MikeE90NC · 06-02-2014, 01:12 PM

Quote:

Originally Posted by AWTT335i

Mouser has 1,322 in stock.

http://www.mouser.com/Search/Product...844-IRF644SPBF

Excellent! Thanks!

MikeE90NC · 06-06-2014, 07:18 AM

This fixed it!

MikeE90NC · 06-17-2014, 07:25 AM

I am getting an input signal error code on the cylinder that I repaired the mosfet on. I replaced the injector and coil on that cylinder and I am still getting the input signal code but no DME code anywhere. The injector is NOT coded yet tho and I was using the first line of injectors initially and now I am on the new ones.

The person that did the mosfet swap said that they must have heated part of it up too much as some copper came out when they pulled off the old one. They told me that they soldered everything back in and repaired the copper. The car ran fine for a week after they fixed it, then the misfire started. I must say that after I changed the coils (before injector swap) and cleared the error codes that the car was running fine for about a minute with no codes tossed then it would throw a code. So possibly not a problem with the mosfet? HELP!!!!

glachhman · 06-17-2014, 12:37 PM

Boy reflecting back this thread saved me.

ntc490 · 09-16-2014, 10:24 PM

Your post helped another car. FWIW, seems like 30BA indicates a problem with bank1 and 30BB is a problem with bank2.

My car threw a 30BA and was barely running. Started and idled okay for about 15 seconds or so, then bank1 AFRs would go totally lean and the car was only running on the 3 cylinders in bank2. Car didn't have enough power to make it up the driveway.

Checked the DME and the MOSFET for injector 3 was bad. Replaced all three MOSFETs for bank1. Put everything back and started the car: fired up good, but was running a little bit rough. Found coil pack on cylinder 3 had died. Replaced that and car runs good now. Thanks for helping us all out!

Chitown335i · 09-30-2014, 12:53 PM

Anyone one that has done this willing to have me send them my dme to replace the transistors or diodes or wtvr it is that is needed? I have similar codes being thrown like 30BB, 30BA, and 3100. I have had the injectors....hpfp...lpfp all checked out still working fine. So leads me to assuming the injectors transistors are fried.... ID REALLY APPRECIATE THE HELP!!! I cant afford a new DME for sure!

AWTT335i · 09-30-2014, 01:14 PM

Quote:

Originally Posted by Chitown335i

Anyone one that has done this willing to have me send them my dme to replace the transistors or diodes or wtvr it is that is needed? I have similar codes being thrown like 30BB, 30BA, and 3100. I have had the injectors....hpfp...lpfp all checked out still working fine. So leads me to assuming the injectors transistors are fried.... ID REALLY APPRECIATE THE HELP!!! I cant afford a new DME for sure!

Just order the injector MOSFETs and take it to a local electronics repair shop, they should be able to knock it out pretty easily.

Chitown335i · 09-30-2014, 01:20 PM

Quote:

Originally Posted by AWTT335i

Just order the injector MOSFETs and take it to a local electronics repair shop, they should be able to knock it out pretty easily.

ive called around a few electronics shops and they all say they wont work on car related parts

03-22-2014, 03:58 PM	#111
glachhman Banned 41 Rep 692 Posts Drives: '07 335i e90 Join Date: Mar 2013 Location: Queens, NY iTrader: (0)	Just ordered 6 transistors from digikey after my dme failed this morning. Just diagnosed it to be cylinder 5 with multimeter. I've soldered many things in the past but I am a bit confused about the heat gun and surface mount. Can the job be accomplished using a soldering iron carefully? Edit just ordered a hot air gun, wish me luck. Last edited by glachhman; 03-23-2014 at 01:26 PM..
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03-23-2014, 10:31 PM	#113
AWTT335i First Lieutenant 11 Rep 368 Posts Drives: E90 M3 Join Date: Aug 2013 Location: United states iTrader: (0)	Here's mine I did last week. Runs great now. Not sure if it's related, but I was getting very minor misfires the first few pulls when beating on the car before the MOSFET let go. Never any codes. Attached Images
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03-24-2014, 10:13 PM	#115
Morpheus Captain 25 Rep 941 Posts Drives: 335i Titanium Silver Join Date: Sep 2008 Location: Cockaigne iTrader: (1)	This should be a sticky
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03-25-2014, 05:28 PM	#116
glachhman Banned 41 Rep 692 Posts Drives: '07 335i e90 Join Date: Mar 2013 Location: Queens, NY iTrader: (0)	Transistors coming tomorrow! https://www.dropbox.com/s/fjhpcpkupu...2018.16.24.jpg
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03-27-2014, 03:03 PM	#117
glachhman Banned 41 Rep 692 Posts Drives: '07 335i e90 Join Date: Mar 2013 Location: Queens, NY iTrader: (0)	Success! Worked for me. I was able to get my car home but looks like the DME took injector 3 with it.
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03-28-2014, 02:09 PM	#119
R1000K3 Major 55 Rep 1,311 Posts Drives: 335i MT Join Date: Jul 2009 Location: USA iTrader: (0)	It is quite risky to remove and mount surface mounted components in case the necessary tools and skills are not there. Especially large components like this where a lot of heat needs to be applied. An optional method is to cut the leads and leave the broken transistors on the board. Then put new transistors on a heat sink and connect them to the board by wires if the component wires needs to be extended. That would minimize the risk for secondary board failure. I dont know how this board i designed but usually they are multi-layers with invisible cross bondings between layers. If a bonding is damaged it is only to trash the complete DME
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04-16-2014, 05:50 PM	#121
Ingeniator Major 34 Rep 1,093 Posts Drives: 07 335XI(90) 09 135I(82) Join Date: Nov 2013 Location: Fort Mac, Alberta iTrader: (1)	Bump for sticky __________________ 07 335XI (A008006) 6AT ~94K miles JB4 G5 ISO VSRF DP's 09 135I M (VK80379) 6MT. Race Project car. 1) Install Cobb/piggyback? and Motiv 600 Kit[HTA3076R w/ tial .82] 2) JRZ or Moton suspension. 3) Build high flow intake manifold with multi-port fuel and relocate OFH 4) Build full cage 5) Complete staged twin setup with HTA4205R [w/Tial 1.16] 6) Complete dry sump system
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04-16-2014, 09:13 PM	#122
waikiki35 Banned 10 Rep 53 Posts Drives: 335i Join Date: Mar 2013 Location: tn iTrader: (0)	hello, I have a bad MOFSET for injector 1... How do I desolder the old one and solder the new one? Is it that complicated? If it is is there a place I can take it to to get it done? Thanks
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06-02-2014, 09:46 AM	#123
MikeE90NC Second Lieutenant 22 Rep 257 Posts Drives: 2007 BMW 335i Join Date: Jul 2013 Location: Somewhere, NC iTrader: (1)	I tried ordering part IRF644B (correct ?) from digi-key and they are showing none in stock!? Is there another place to buy them????
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06-06-2014, 07:18 AM	#126
MikeE90NC Second Lieutenant 22 Rep 257 Posts Drives: 2007 BMW 335i Join Date: Jul 2013 Location: Somewhere, NC iTrader: (1)	This fixed it!
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06-17-2014, 07:25 AM	#127
MikeE90NC Second Lieutenant 22 Rep 257 Posts Drives: 2007 BMW 335i Join Date: Jul 2013 Location: Somewhere, NC iTrader: (1)	I am getting an input signal error code on the cylinder that I repaired the mosfet on. I replaced the injector and coil on that cylinder and I am still getting the input signal code but no DME code anywhere. The injector is NOT coded yet tho and I was using the first line of injectors initially and now I am on the new ones. The person that did the mosfet swap said that they must have heated part of it up too much as some copper came out when they pulled off the old one. They told me that they soldered everything back in and repaired the copper. The car ran fine for a week after they fixed it, then the misfire started. I must say that after I changed the coils (before injector swap) and cleared the error codes that the car was running fine for about a minute with no codes tossed then it would throw a code. So possibly not a problem with the mosfet? HELP!!!!
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06-17-2014, 12:37 PM	#128
glachhman Banned 41 Rep 692 Posts Drives: '07 335i e90 Join Date: Mar 2013 Location: Queens, NY iTrader: (0)	Boy reflecting back this thread saved me.
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09-16-2014, 10:24 PM	#129
ntc490 Registered 0 Rep 1 Posts Drives: 2007 335i Join Date: Sep 2014 Location: United States iTrader: (0)	Your post helped another car. FWIW, seems like 30BA indicates a problem with bank1 and 30BB is a problem with bank2. My car threw a 30BA and was barely running. Started and idled okay for about 15 seconds or so, then bank1 AFRs would go totally lean and the car was only running on the 3 cylinders in bank2. Car didn't have enough power to make it up the driveway. Checked the DME and the MOSFET for injector 3 was bad. Replaced all three MOSFETs for bank1. Put everything back and started the car: fired up good, but was running a little bit rough. Found coil pack on cylinder 3 had died. Replaced that and car runs good now. Thanks for helping us all out!
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09-30-2014, 12:53 PM	#130
Chitown335i Private First Class 28 Rep 182 Posts Drives: 2007 Smoky Graphite 335i Join Date: May 2014 Location: Joliet, IL iTrader: (0)	Anyone one that has done this willing to have me send them my dme to replace the transistors or diodes or wtvr it is that is needed? I have similar codes being thrown like 30BB, 30BA, and 3100. I have had the injectors....hpfp...lpfp all checked out still working fine. So leads me to assuming the injectors transistors are fried.... ID REALLY APPRECIATE THE HELP!!! I cant afford a new DME for sure!
	Appreciate 0 Quote