Mystery Component

Thread Starter

mje

Joined Feb 2, 2020
6
Hi Folks,

I have a circuit component that has failed in a marine tiller unit (Steering Unit) my best guess is that it's a diode of some sort as it is the first component on a power rail. Does anyone recognize this component? 12 volt as you can tell an old board.


Thanks in advance :)
 

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ericgibbs

Joined Jan 29, 2010
9,575
hi mje,
Welcome to AAC.
There are signs of serious corrosion on some of those components, why do you think the 'diode' has failed.?
E
 

Attachments

Thread Starter

mje

Joined Feb 2, 2020
6
Hi Folks,

I have a circuit component that has failed in a marine tiller unit (Steering Unit) my best guess is that it's a diode of some sort as it is the first component on a power rail. Does anyone recognize this component? 12 volt as you can tell an old board.


Thanks in advance :)
My guess is a diode in a 194-04 case such as an MR751 look carefully, there may be a diode symbol on the outer surface.

https://www.onsemi.com/products/discretes-drivers/diodes-rectifiers/rectifiers/mr751
Thank you So much!!! Your dead right! I took it out of circuit and that is what was printed on the underside of the component. It's over forty years old. I was stumped "MR751" could just be made out. You are a master! thanks again!!
 

debe

Joined Sep 21, 2010
1,156
Thats very similar to an Autohelm 1000 tiller pilot i had in 1981. Very similar circuit & operation, i have the workshop manual with circuits for mine. Pretty sure that diode is for reverse polarity protection.Autohelm 1000.1.jpg
 
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Thread Starter

mje

Joined Feb 2, 2020
6
Thats very similar to an Autohelm 1000 tiller pilot i had in 1981. Very similar circuit & operation, i have the workshop manual with circuits for mine. Pretty sure that diode is for reverse polarity protection.View attachment 198170
Yes, you're correct, same in my circuit, quite expensive to buy new or replace the old one. I'll keep trying to keep the old one alive
 
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