2001 Mercruiser 5.7 EFI/TBI Scan Tool

ejput

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I saw this on another forum at some point. Trying to determine if if the connector I have is capable as a scanner hook up. Additionally, someone posted a cheaper alternative to buying the actual scan tool. Connector.jpgConnector part number.jpgConnector LED scanner.jpg
 

ejput

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I'm not sure as well...hoping something!! If not, I'll go about fixing it the old fashioned way.
 

Lou C

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That diagram reminds me of what you had to do to pull codes from the EFI system on a late 80s Toyota....paper clip trick and turn on ignition, the check engine light would blink out a code, that was what you got!
 

alldodge

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That is a MEFI (1 to 4) connector and while there are not many codes can be read, if there is one it can be done as your pic shows. Use a 12V resistor LED or a voltmeter with a tone function
 

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ejput

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Sep 14, 2026
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That is a MEFI (1 to 4) connector and while there are not many codes can be read, if there is one it can be done as your pic shows. Use a 12V resistor LED or a voltmeter with a tone function
That helps a lot!! Thanks
 

Fun Times

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Like mentioned above, if you're just wanting to read trouble fault codes on the MEFI ECM's only type then the following way using a multimeter is a safe and easy effective way to do it...

If you are wanting more viewable data then maybe checkout a MR500 Marine Scanner for your engine manufacturer model on both Ebay and Amazon as it may be of some help too though seemingly pricey as well.
 
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