In this video I show you how to replace the transistors better known as MOSFETs on your ECU or DME. The early MSD80 equipped cars suffer a problem where the transistors that fire the injectors eventually fail.
From what I’ve been told this is due to the ignition coils pulling too much power from the circuit causing the injector transistors to fail. They eventually fixed this issue on the later 2008 and newer cars by introducing a newer ECU called the MSD81.
None the less you can fix this problem without needing to replace your entire ECU. The fix is to install stronger transistors which will not fail in the future. That is what I did in this video and I show you how to replace all your transistors.
You could do this as preventive maintenance or if you’re getting a code for 30BA or 30BB. If you have that code your car will be running on just three cylinders so you can limp it off the road.
In rare instances it could be a failed injector but you could disconnect the injectors and try clearing the code, if it remains then you have a bad transistor. I also show you how to test for a failed transistor. If you’re getting a 30AB or 30BB code then just order the transistors and replace them regardless.
Your can purchase the upgraded replacement transistors here (affiliate):
https://amzn.to/2ZhwrNe
You can purchase the hot air station I show in this video here (affiliate):
https://amzn.to/31KgQr1
You can purchase the solder flux here (affiliate):
https://amzn.to/2KJE1fz
Special thanks to Eurocharged of Houston and Spool Performance LLC for helping out with a spare transistor to keep my car running 🙂
If this is the first video you’re catching of my consider subscribing, I upload regularly.
Thanks for watching!
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More on what high power mosfet could be used. See trace showing 380V is reached(Probably on a stock car): https://bimmerprofs.com/30ba30bb-repair-msd80/
+The IRF644 250V/14A is commonly sold as replacement :https://www.mouser.com/datasheet/2/427/sihf644s-1768609.pdf
+In this video FDB14N30TM 300V/14A : https://www.onsemi.com/pub/Collateral/FDB14N30-D.pdf
+Suggested from BimmerProf SiHB30N60 600V/29A: https://www.vishay.com/docs/91453/sihb30n60e.pdf
+From my own search using BimmerProf suggestions of parameters. Maybe completely useless to go this high but, maybe on modded cars trying to use ELDOR coils to the MAX??(ME not EE use at own risk): NTB095N65S3HF 650V/36A https://www.mouser.com/datasheet/2/308/NTB095N65S3HF-D-1539963.pdf
I have not had the originals fail on my 07 with 180K yet…
? On the mosfets upgrade do you need to do any flashing the the ecu or is it plug and play meaning put on and start the car?
Will a fried ecm cause drive train malfunction?
On Startup, what is that beepbeep…..BEEP we hear? I keep hearing it and OCD needs to know!
You can also use solder paste, which is meant for hot air reflow soldering. It contains small particles of solder and flux in a syringe that you apply to the PCB. After removing the older FETs, I recommend using the solder wick and the iron to remove the older solder first, then apply some paste. You need just enough to cover the exposed PCB pads. Then place the part in the correct spot. You shouldn't need to apply too much downward pressure on the part. Once you've used the hot air gun to heat the board and the part, the solder liquefies and actually sucks the part down to the board due to the solder's surface tension. The part will usually self center on the pads when this happens.
Use isopropyl alcohol to clean the board. Lysol just kills germs.
I had this happen to my MSD80 as well and replaced the MOSFET with the same parts shown in the video. It's been working well for 2 years at 20psi in the midrange using the one step colder plugs gapped at 0.022". I am using the Delphi pencil coils.
If I were you, i’d delete this video since you have another recommending the MSD81. If you simply replace the transistors on the MSD80, they will fail again. You must replace them with upgraded ones, and snubbers, along with coding in order to fix the logic.
need help asap… my car had the same code, i had my mosfet tested and they were good but i still was getting the code and bad misfire in cylinder 1,2,3, change injectors,coils and spark plugs. so i bought a ecu and the misfire went away. so km guessing the problem was ghe ecu. so i want to fix my ecu but i cant figure what the problem is if the tester saying the mosfet are good
Dude you are the best right now , I'm in Houston area how much you will charge me for this job since I don't have the tools for and I need my baby running, it's my dayli
Ok I was thinking it wouldn't start when I saw you burning those mosfets for so long. Next time just put the whole ECU in the oven on 100°C. Preheat and then work on it. It will be a lot easier and you will put much less heat stress on the elements.
Hey hope you can see this comment but I have a 2007 335i thinking about going stage 2 I have the supporting mods but do you think my mosfets would go out with a tune ?
Is there a reason you went msd81? Did the install not work? I had code 30ba before having mine replaced. Now I have 2e32, 2e33, and 2e35 if you could let me know I’d really appreciate it. I watch all your content. A huge fan to say the least!
I did a 3rd gear pull the other day in MHD stage 2+ and as soon as boost hit BAM! Misfires. Swapped coils and plugs and reset code and then I got the 30BA injectors 1,2,3 or DME internal fault code. Replaced all 6 of these mosfets and car is back to normal! Wanted to say thank you for posting this, I used the same ones you list here on amazon 10 for $10! Thanks again
I drive a 07' 335i that is running MSD80 with an 30BB injector x,y,z order DME, internal error. Bank 2 is misfiring.
The MOSFET's tested fine, anyways I upgraded them. The error remains.
I ruled out the injectors by upgrading to index12 and a ground by doing a noid light test. No signal or light is seen on injectors 4-6, which is so post to indicate that injectors 4-6 are not receiving signal.
Anyone familiar with the MSD80 board that can help me trace the problem?
I was considering upgrading to a used MSD81, however, I need to find a reliable vendor then code the UIF to add a secondary VIN (mine). Meaning I would have to be fine with the primary VIN (donor) on the DME.
Just wanted to say thanks. I was driving home from work on day, went to do a pull, got a CEL, and my car was saying cylinder 1, 2, 3 misfire. I swapped the plugs and coils and got a code for injector 1, 2, 3 or possible DME internal error. Thanks to this video i was able to have my mosfets replaced (cylinder 2 was bad) for $145 and saved myself a diagnostics fee ($120) and the cost of possibly having to clone my DME ($300).
I plan to solder my MOSFETs. Any tips on a beginner with a hot air gun?
can someone please help me. I have MSD81 with codes 30bb and 30ba. Any ideas of what this could be or who should I contact?
The anti-theft system on my 2008 328i activeted it cranks but won't start I can't drive it anywhere help please
Hi I just watch the video (btw thumbs up for your job on the car and sharing it ). I've notice that you read your car with your phone. What is the name of the software that u use ? Thanks in advance
HI I JUST BOUGHT AN 320i E90 9/2005 WITH AN, N46B20B ENGINE WITH MISFIRE
I HAVE REPLACED 4 PLUGS AND COILS AND STILL NOT GOOD, DO YOU THINK I HAVE THE SAME ISSUE ?
FEEL FREE TO EMAIL ME ( piper_ash@hotmail.co.uk ) MANY THANKS
ASH
I believe this is the first video, that I've watched of yours, you actually went to a shop. Thank you!
So I'm not the only n54 BMW enthusiast that uses Eurochaged.
Any company that focuses on high end vehicles ($250K+), but still has love for the bastard child 335i, are true gear-heads.
Eurocharged ATX
7 Applegate Cir #400, Round Rock, TX 78665
(512) 777-2799
https://maps.app.goo.gl/JTAwwnEXKDRSQ3Xf9
Will bad mofsets also cause the car not to start?
I'm really confused with this series of DME videos. If you upgraded the mosfets in MSD80, why was the very next video you trying to changing to MSD81? Did you blow the upgraded mosfets again?
My 335! X6 has a misfire #3 after my brother accidentally ripped the brown wire that goes to the coil #3, we fixed it properly and checked the coils & injectors..ect the ( we checked #3 plug by Voltmeter and it reads 15V) while the rest lower around 11Vot?? And Still no spark! One guy said it need a new ECU/DME wich I don't think so, now I'm expecting the problem would be a burned (MOSFETS) but I sent the car to BMW service yesterday for final inspection to be sure, let's see what they say, Actually I hope they say you need a DME so I can smile and leave and start the process of changing the MOSFETS.
Smh just got off the phone with eurocharge of Houston and they say that they don’t do MOSFETs
install diff brace for better grip