On/ off switch for elec. fuel pump

I need some help on installing a switch to turn off the elec. fuel pump .

I want to install the switch on the instrument panel. To interrupt the positive wire with the switch, which wire number do I interrupt coming from the switch/ fuse panel?

I have been told it is number 1 wire. Don't know if that is correct and if it is, where do you read the number ( i.e. What part of the cannon plug - front or back do you read the number from?

Fuel Pump Switch

Do NOT switch power coming from pin 1 of the switch module because that will shut off the avionics cooling fans. The avionics could overheat. Instead, insert the switch in the wire that is connected to pin 29 of the fuselage D-Sub connector. That wire should be 18 AWG with RED insulation. It should be easy to find because it is the only 18 AWG wire. All of the rest on the fuselage connector are 22 AWG.
I have a fuel pump switch for ground operations. I never shut the electric pump off while flying.

The builder of my 12 put a Klixon breaker next to the fuel valve. That seems a lot easier than putting it in the panel. I use it instead of pulling the fuse on the ground (avionics work, etc) but like Joe never use it in flight.

Jim -

Follow Joe's advise.

Also, if you want the fuel pump switch to match the rest of the switches installed on the RV-12 you can order an Otto K1ABAPCABA switch.

Jim garrett said:

I need some help on installing a switch to turn off the elec. fuel pump .

I want to install the switch on the instrument panel. To interrupt the positive wire with the switch, which wire number do I interrupt coming from the switch/ fuse panel?

I have been told it is number 1 wire. Don't know if that is correct and if it is, where do you read the number ( i.e. What part of the cannon plug - front or back do you read the number from?

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In this rare case I did not locate the wire by pin number on a plug but by tracing it in the tunnel. It was pretty simple with mine as it was a distinctive, stiff red wire, thicker than all the others and, well, RED. Here's the write-up: Fuel Pump Wiring
My switch is on the panel, where others have their AP disconnect button. I used a DPST switch to run the other wire to the EMS and let SkyView know in which position the switch is so I can show the on/off status on the engine display.

As another data point for the switch location ... I located my fuel pump switch along with a switch for my left landing light above the AV-50002 Ignition & Start module aligned with the ignition switches.

I wanted two landing lights for wig-wag operation and added the switch to limit the steady on current draw ... the left light can be turned on during short final and off after landing.

I don't have lights, so I just wired the fuel pump into that switch. It's easily done in the wire bundle just aft of the footwell angled partition and under the centerline floor panel.

RFSchaller said:

I don't have lights, so I just wired the fuel pump into that switch. It's easily done in the wire bundle just aft of the footwell angled partition and under the centerline floor panel.

Click to expand...

Are the AWG wire sizes and circuit board traces current capabilty sufficient? If so, sounds like a nice solution.