Locating diagnostic plug on 300E
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Joined: Mar 2008
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1987 300E
Locating diagnostic plug on 300E
I bought my 1987 300E a couple months ago and I've slowly been trying to fix the various problems it had. It's perfectly drivable in it's current condition but it will need some work later. Currently I'm having a vacuum problem and this is causing all sorts of fun problems. The biggest is my ABS system. It will randomly interrupt my braking, and then after a bit the system will fail and the light will come on. I figured it would be easy to find the diagnostic port and read the fault code for the system but I've hit a snag.
I can't find the diagnostic port for the life of me. I know where the 9 pin connector on the drivers side is and I can find the ABS computer and the ECU behind the battery with the OVP relay next to them. Where is the actual diagnostic port. I whipped up a cable for it based on the simple design here and figured it'd be a 5 minute operation.
Can anyone help me out?
I can't find the diagnostic port for the life of me. I know where the 9 pin connector on the drivers side is and I can find the ABS computer and the ECU behind the battery with the OVP relay next to them. Where is the actual diagnostic port. I whipped up a cable for it based on the simple design here and figured it'd be a 5 minute operation.
Can anyone help me out?
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Joined: Jun 2007
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From: Columbus, Ohio
2004 C230SS & 2007 GL450
Under the hood, driver's side. You will see a round black screw cap directly behind the hydraulic fluid reservoir. This is the 16-pin port. Is this what you are looking for?
Thread Starter
Newbie
Joined: Mar 2008
Posts: 5
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1987 300E
I am looking for the 16 pin connector but I could not find it on the drivers side. On the drivers side I can only find the 9 pin connector which is right where you said it was. I've looked all over the drivers side by the fuse box and over on the passengers side by the OVP relay and computer units.
