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speedracer92 speedracer92 is offline
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Join Date: Apr 2019
Location: The Woodlands, TX
Posts: 310
Originally Posted by darrin View Post

take a look at the wiring schematic at the following link --

specifically, note how the dme relay completes the circuit between pin 30 "+12 volt from battery unfused" and pin 87b "+12 volt to fuel pump via fuse 3"

this suggests to me that the f9 IS the source of your always running fuel pump, as the same result would occur if you simply inserted a jumper wire between pins 30 and 87b
Thanks. Great post you linked to. I definitely think the SSR is the cause of the fuel pump running, but what I don't understand is that no power should be going to the SSR at all when the ignition is off, correct? So, the SSR will cause the pump to go until the battery dies, but it shouldn't.

From the MFG --> With the key in the off position the Pump-Prime feature is electrically disabled and cannot allow current to flow to the fuel pump. With the ignition off, the Solid-State relay is designed to not draw or provide current.

This is the second one - so something has to be wired wrong in my car. But even with the OEM DME, power would be going to it, but since it doesn't have pump prime, nothing is powered with it?
1987 911 Carrera Targa
Old 05-04-2020, 06:51 PM
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