Location for yellow fuel pump relay wire

[OSI930]

I have been working on a 1980 SC recently and I am trying to locate the yellow wire that, according to the wiring diagram, runs from #87 on the fuel pump relay to the ignition switch. I see the connection below the fuse panel but someone has cut the yellow wire 3" past the connection. I can see the yellow wire from the ignition switch and I see where it plugs into a round, rubber connection under the dash. I assume it then makes its' way into the trunk area around the left side hood strut area but I can't pick it up from there. Since the yellow wire was cut, I don't know if I am looking for a single yellow wire or the yellow wire exists in a group of wires. Thanks in advance and thanks to everyone who have already offered their advice.

[Early_S_Man]

Terminal #50 on the ignition switch is the source of that Yellow wire.

[OSI930]

Thanks Warren. I have studied your diagrams and posts many times. They have been very helpful and the colors are great. I can see the yellow wire from the ignition switch and the connection into the sheet metal below the dash. I guess I am trying to find the T1e connection(on luggage compartment floor). I have the T2e connection and about 3" of yellow wire past the connection and that is where it ends. I am just not sure where the T1e connection is and if the yellow wire between T1e and T2e is a single wire or is it bundled with other wires.

[OSI930]

I spent a good part of the afternoon trying to locate where the yellow wire from the ignition switch goes through the sheet metal into the trunk. There are several round rubber connections located on the sheet metal behind the left hood strut that could contain the yellow wire from the ignition switch but lightly pulling on the connection does not disconnect. Does anyone know if the connection actually does disconnect? Thanks.

[OSI930]

Is there any way to tell by looking at a wiring diagram if the wire you are looking for is a single wire or grouped with other wires contained in the harness?

[Jim Sims]

"a single wire or grouped with other wires?"

Information can be gleaned from the wiring digrams and associated key(s). One will note that the yellow wire leaving terminal 50 of the ignition switch passes through a connector symbol with the letter "T" and with smaller characters "5" and "6f". The key will tell you (based on the "T" and the "6" in the "6f") this is a six-pole connector (a connector capable of connecting six separate circuits or wires) and for this year the "f" in "6f" means to look for the connector below the instrument panel. The "5" indicates that the yellow wire passes through terminal 5 of the connector. This is a start but the key also indicates there is a 2nd six-pole connector under the instrument panel. Further consideration of the wiring diagram will show that the red/black wire leaving terminal 15 of the ignition switch also passes through connector "T6f" but through terminal 6. One can also note that two of the three red wires leaving terminal 30 of the ignition switch also pass through connector "T6f" through terminals 2 and 3 on their way to the battery positive post. So to find the correct six-pole connector under the dash I would look for one that has the two red wires and the red and black wire and a yellow wire going to it.

The wiring dirgram also appears to indicate that the yellow wire you are tracing (the one that goes to the fuel pump relay in the luggage compartment) first passes through a single pole connector in the luggage compartment then it branches off a 2nd yellow wire before going through a two-pole connector in the luggage compartment before connecting up to the relay base. I would first seek out these connectors in the luggage compartment before doing more under the instrument panel.

Good luck with the fuel pumps.

Cheers, Jim

[OSI930]

Thanks for coming through again, Jim. I agree that I should continue my search in the luggage compartment. As I stated in an earlier post, I think I can see a round 6 pin connection in the luggage compartment, behind the left hood hinge but pulling on this connection where it attaches into the sheet metal itself does not yield. I can see the yellow wire from the ignition switch and can follow it to where the 6 pin connection attaches to the sheet metal inside the car, below the dash. Has anyone tried to detach one of these round rubber connections from the sheet metal. I can see two of them , one in front of the other but the other one looks like it does not have 6 wires contained inside.

[Jeremy Cottrell]

OK, here we go! I hope this helps. Best of luck - JC

[Jeremy Cottrell]

Also make sure that the plug is hooked up at the back of the sensor plate. You can't see it, you have to feel for it. If it is disconnected the pump will run all the time, I believe. It is supposed to sense movement in the sensor plate during crank mode and it sends a signal to turn on the pump.

[OSI930]

Thanks Jeremy. Those pictures will give me something to look for. What year car are those pictures from? Also, I found the brown/black wire from the air sensor plate. It was cut too. I hooked it up a while back and it is working properly.

[Jeremy Cottrell]

Ah ha! Great, I hope it all works out for you. The car I took the pix of was an 82 SC. Good luck!

[Brother]

Here is the picture to go with what I PM'd you.