Bad mosfet

LncGmz

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Jun 27, 2017
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Who here replaces mosfets? I have a bad injector one mosfet, MSD80 of course.
 

Hokie_335i

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Jul 29, 2017
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2009 E90 335i 6MT
They're fairly easy to do. I replaced mine in my MSD80 myself. Cost about $15 in parts plus $70 since I didn't have a hot air soldering iron so I bought one. Took about 30 minutes to do the job once setup. Bought new mosfets off of Digikey and didn't have any issues afterwards. I replaced all 6.
 
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Cheezy

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Nov 7, 2016
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They're fairly easy to do. I replaced mine in my MSD80 myself. Cost about $15 in parts plus $70 since I didn't have a hot air soldering iron so I bought one. Took about 30 minutes to do the job once setup. Bought new mosfets off of Digikey and didn't have any issues afterwards. I replaced all 6.
What a hardass! I like it! Were you worried about the heat sensitivity of the board or just cakewalked through it? If mine ever burns up i might consider doing it myself.... or spending $500 and getting msd81
 
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Hokie_335i

Specialist
Jul 29, 2017
51
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North Carolina
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2009 E90 335i 6MT
What a hardass! I like it! Were you worried about the heat sensitivity of the board or just cakewalked through it? If mine ever burns up i might consider doing it myself.... or spending $500 and getting msd81

I was in college at the time and was lucky that my good friend was in a graduate electrical engineering program and built much more complex boards with smaller components than the MSD80. I am fairly handy with those kind of things but he was sitting close by watching in case I was about to mess something up. However, I was conscious of the board temps and adjusted the hot air soldering gun accordingly. Start low with the heat and work your way up slowly until you have enough heat to melt the solder and release the mosfet. I did a fair amount of research on it prior to tackling it. I'd definitely recommend a hot air soldering station if you were to tackle it yourself. Using a traditional soldering iron probably would have put too much heat into the board through direct contact. I used this one:

 

langsbr

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Apr 5, 2017
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Msd81 dmes are dirt cheap from junkyards. The issue was you had to also buy the key and cas. Then have it programmed. Now that Omar has the tool that can virginize the DME, he sells a guaranteed working virginized one for 500
 
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langsbr

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Apr 5, 2017
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I think both prices include the msd81, the 700 is if you need a new key fob. I asked him how much it was if I provided the msd81 and he prefers to do it since he can confirm it is working. And probably because they are only 50 bucks lol.
 

dyezak

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May 4, 2017
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I think both prices include the msd81, the 700 is if you need a new key fob. I asked him how much it was if I provided the msd81 and he prefers to do it since he can confirm it is working. And probably because they are only 50 bucks lol.

Reading is fundamental. I think you are correct:

$500 - Includes
MSD81 ECU , Coding CAS, Coding Customers Key
$700 - Includes
MSD81 ECU, Coding CAS, New Key Fob, Coding New Key

My bad
 

langsbr

Captain
Apr 5, 2017
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I think that is what is being done - he virginizes the MSD81 so you don't have to get a new virgin one from the dealer, then codes it and the CAS together with your car's VIN. I don't know if Omar is on this forum or his screenname.