fuse for fuel pump

Randy Webb · 06-29-2004, 04:34 PM

I have a 1973.5 coupe and after pulling all fuses (top 10 & bottom 8 in front boot + the 3 on the rear elec. panel) it still runs!

My car has only a single relay (for the horn) - but I pulled it too -- still runs.

This is the very first of the CIS cars, but I can't figure out why the fuel pump won't shut off.

I can't believe the factory hot wired the thing -- maybe a PO did something?

Any ideas on hidden fuses or relays on this car?
The factory schematic shows a red/green wire to the pump from fuse 7 - but that is not correct.

Jim Sims · 06-29-2004, 04:52 PM

73.5 CIS as delivered from the factory doesn't have a relay for the fuel pump nor is the fuel pump on a fused circuit. If you study the circuit diagram further you will discover the red/green wire goes to the hot side of fuse 7 and the red/black wire also connected to the hot side of fuse 7 provides power to the hot side of fuse 7 directly from the ignition switch. The ignition switch receives power directly from the battery without going through a fuse. To disable the fuel pump one can separate the two-pole connector in the wiring to the pump; this connector is located on the driver's side of the engine compartment near the electrical chassis. Cheers, Jim

cowtown · 06-29-2004, 05:12 PM

Randy, this threw me for a loop as well. Deja vu - Jim bailed me out. I ended up recreating the later fuel pump circuits - if you need a diagram I can send one.

Randy Webb · 06-29-2004, 05:32 PM

Thanks much, Jim. BTW, after looking at some other threads - you have got a really clean car.

I should have checked more carefully - it never occurred to me that they would run it to the hot side of a fuse....

Cow town - You mean you changed your car's wiring so it incorporated a relay? If so, yes, thanks, I would like to get the details.