Where to buy electric components to fix M998/HMMWV PCB boxes?

NDT

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Those mosfets are rated at like 70 amps each which should be more than adequate for normal operation. My theory is they get blown up when people (GP and Uncle) slave off a totally dead battery HMMWV and remove the slave cable while the box is still cycling, which sets up a voltage surge anomaly that blows them.
 

dhaumann69166

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Looks like they let the magic smoke out in a spectacular manner. Any idea on why they may have failed?
Nice job on the repair!
100% my fault they burned. I unhooked my S3 box with the batteries still hooked up. When I pulled the connector under the dash there was a spark hot enough to leave a small notch in threads of the connector.
Kinda surprised there wasn’t more damage in the box. I had major corrosion in my wiring harness side of the top connector which led to the 24v hot wire in the middle shorting directly across to the glow plug wire. Only found it by wiggling the wires one day and it got hot enough to smoke.
 

antennaclimber

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I know the feeling.
Once I unplugged a 330 watt paging transmitter while it was still transmitting. I thought it was off the air but it was still putting out power. Any unexpected arcs can be surprising when you experience them.

At least you were able to accomplish the repairs by yourself with a minimum amount of $$ spent. And I'm sure that it will be a good example to others to prevent the same from happening to them.

Thanks for the write up.
 
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