Matt Hendrickson

Dave51

That looks like Fuse 8 but that's OK.

Is that the 1996 manual?

What means this?



Did you check the length of A22 Red for shorts? And the length of DK GR?

Did you try a new relay? Not usual, but turn over all the stones.

Matt Hendrickson

Red ohms out perfectly to the pcm. Green/ white was also good, but went ahead and already ran a new line. Brand new relays for the fuel pump and the ASD.

I think the was supposed to be "fuel pump". Lol

My friend that owned this before found that schematic, then promptly lost it.

Dave51

How about bypassing the PDC. Run your new line directly to the battery. Use a fuse inline. Start out with like a bulb, test lamp, or multimeter so you don't fry the pump.

If that works then try the pump.

Matt Hendrickson

I had thought about that, but then the fuel pump would run even when the ignition was off. I'd have to disconnect the battery at every stop. Thank you for the suggestion though.

I know the short is happening behind the fuel pump relay. I know the power and ground to the fuel pump are good. I know the lines going to the pcm are good. The fuel pump started when hooked up outside the tank. I'm beginning to suspect it could be grounding out on the tank if that makes sense. Here's a pic of the wiring inside the pump.


Red is power, black is ground, blue is to the fuel gauge. I'm curious why it is going back to the cap and grounding there too. Interesting thing to note, if I only have the power connected, the ground disconnected, and I run voltage down the hot line, it is grounding. I don't understand that, as the brand new line I ran is perfect. It must be also grounding out at the tank.

Dave51

If that worked you'd know the problem was in the PDC and need to troubleshoot that area.

Dave51

You still have a ballast resistor in there someplace?

jordan96xj

I think you will find that the black wire that goes by itself out to the edge of the fuel module "cap" (mounting face plate) is the ground for the pump motor. The black that comes into the module with the other wires is the ground needed by the blue wire for detecting the voltage provided by the fuel level sensor.

You refer to black being ground (singular) but I think in your setup you have 2 separate ground wires. One for level sensor, and one for pump. The one for the level sensor is coming from the PCM (according to the information you have provided. I have a 96 which is wired differently).

Matt Hendrickson

So with that in mind, the original wiring, a 5 prong harness, colors shown earlier in the thread, should I also have the second wire grounded?