Fuel pump relay wiring?

2006 FORD RANGER
306,000 MILES • 3.0L • V6 • 2WD • AUTOMATIC
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BMAYFIELD
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  • 3 POSTS
I have an intermittent problem on my truck listed above. At times, the fuel pump does not activate when the key is switched on. There’s no rhyme or reason when this happens. Over the past few months, I have tried a new fuel pump relay and fuel pump inertia switch. The issue still occurs sometimes. If I remove the fuel pump relay and place a jumper wire across the 2 slots in the fuse box to activate the fuel pump, it turns on and the truck cranks/runs fine. That tells me that the wiring from there to the fuel pump is good.

I have removed the fuse box from its bracket and checked the underside of the box for any broken/brittle/corroded wires on the relay slots. The wiring looks fine there. I checked the under-hood ground connections on the inner fender well and they looked good as well. Any ideas?

Does anyone have a wiring diagram of this circuit? The relay has 2 pins to power the fuel pump and 3 pins on the other half of the relay. I’m trying to see the what the 3 pins are for.
Jan 20, 2023 at 4:52 AM
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BORIS K
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 836 POSTS
Hello,

Looking at the work already done you possibly have an issue with the inertia cut off switch.
see image 1.
The cutoff switch routes the power supply wire, dark green/yellow from the fuel pump relay, see image 2 and 3.

A good video:
https://youtu.be/pgHVJrncMC0

The switch will not be tripped but it might have a bad connection.

Hope this helps.

Cheers, Boris
Jan 20, 2023 at 9:41 AM
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BMAYFIELD
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  • 3 POSTS
I’ve already replaced the inertia switch, but I will check the connections. Thanks for the wiring diagram.
Jan 20, 2023 at 11:36 AM
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JACOBANDNICKOLAS
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Hi,

I noticed we haven't heard from you for a couple of days. Have you been able to make any progress? We're interested in knowing.

Let me know if I can help in any way or if you have questions.

Take care,

Joe
Jan 22, 2023 at 9:22 PM
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BMAYFIELD
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  • 3 POSTS
I verified the connections at the inertia switch are good. Currently, the truck is not having this intermittent issue. If it starts happening again, I will check the wires feeding into the bottom of the under-hood fuse box that connect to the fuel pump relay.
Jan 23, 2023 at 11:22 AM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

Thank you for the update. If there is anything we can do to help, let us know.

Take care,

Joe
Jan 23, 2023 at 5:42 PM