1987 Ranger 2.9 Secondary Fuel Pump won't run
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Fuel pump relay does use Computer pin 22 as its activation ground
Computer only Grounds FP relay for 2 seconds with Key On, but it does that each time key is turned from off to on
It won't ground pin 22 full time until engine RPMs are above 400, its a safety thing, cranking speed is 200rpm
You can ground pin 22 wire at the OBD1 connector in engine bay, look here: https://www.therangerstation.com/tec...ipped-engines/
Fuel Pump slot is labelled
That's the pin 22 wire, so if you Ground that slot then when you turn on the key the FP relay will activate full time
Ford used 2 types of relays
Mini relay seen here: https://www.gtsparkplugs.com/images/...iring-840x.jpg
Micro relay seen here: https://www.gtsparkplugs.com/images/...lay-wiring.jpg
Standard relay numbers are 30, 85, 86, 87 and 87A
Ford may use 1, 2, 3, 4, and 5 numbering, in what ever order they want, lol
But if you look at the relay base you can easily see what is what
In any case 30 and 87 will pass the 12volts to run pump
85 and 86 are used to activate the relay, to connect 30 and 87
There is no polarity, as long as 85 and 86 has 12v and a ground relay will close, doesn't matter which is which
87A may or may not be there on some relays
Fuel pump relay does use Computer pin 22 as its activation ground
Computer only Grounds FP relay for 2 seconds with Key On, but it does that each time key is turned from off to on
It won't ground pin 22 full time until engine RPMs are above 400, its a safety thing, cranking speed is 200rpm
You can ground pin 22 wire at the OBD1 connector in engine bay, look here: https://www.therangerstation.com/tec...ipped-engines/
Fuel Pump slot is labelled
That's the pin 22 wire, so if you Ground that slot then when you turn on the key the FP relay will activate full time
Ford used 2 types of relays
Mini relay seen here: https://www.gtsparkplugs.com/images/...iring-840x.jpg
Micro relay seen here: https://www.gtsparkplugs.com/images/...lay-wiring.jpg
Standard relay numbers are 30, 85, 86, 87 and 87A
Ford may use 1, 2, 3, 4, and 5 numbering, in what ever order they want, lol
But if you look at the relay base you can easily see what is what
In any case 30 and 87 will pass the 12volts to run pump
85 and 86 are used to activate the relay, to connect 30 and 87
There is no polarity, as long as 85 and 86 has 12v and a ground relay will close, doesn't matter which is which
87A may or may not be there on some relays
I have this relay here :
Standard Motor Products RY71T Ignition Relay https://a.co/d/8rzljKw
contact 1: I get battery voltage
contact 2: I get battery voltage
contact 3: 0v
contact 4: I get battery voltage.
I assume 1&2 are 85 & 86.
3 is 30 & 4 is 87.
Yes the 2 smaller pins/slots are 85 and 86, low amps
Larger ones are for Load, fuel pump power
With relay unplugged
Slot 85 or 86 should only have 12v with key on, the other one is the ground from computer pin 22
30 or 87 should have 12v all the time, from fuse or fusible link
A relays 85 and 86 is just a coil of wire, so if relay is plugged in and you test wiring at the base both would show 12v with key on, that just means that coil of wire inside relay is not broken
One will be Grounded by computer and thats when the Coil of wire becomes an electro-magnet pulling the relay closed, connecting 30 and 87
This picture shows Ford numbering: https://www.ebay.com/itm/353753792835
1 and 2 are 85 and 86
3 and 4 are 30 and 87
The one in the picture also shows a diode on 1, so may not work in all bases
Larger ones are for Load, fuel pump power
With relay unplugged
Slot 85 or 86 should only have 12v with key on, the other one is the ground from computer pin 22
30 or 87 should have 12v all the time, from fuse or fusible link
A relays 85 and 86 is just a coil of wire, so if relay is plugged in and you test wiring at the base both would show 12v with key on, that just means that coil of wire inside relay is not broken
One will be Grounded by computer and thats when the Coil of wire becomes an electro-magnet pulling the relay closed, connecting 30 and 87
This picture shows Ford numbering: https://www.ebay.com/itm/353753792835
1 and 2 are 85 and 86
3 and 4 are 30 and 87
The one in the picture also shows a diode on 1, so may not work in all bases
Yes the 2 smaller pins/slots are 85 and 86, low amps
Larger ones are for Load, fuel pump power
With relay unplugged
Slot 85 or 86 should only have 12v with key on, the other one is the ground from computer pin 22
30 or 87 should have 12v all the time, from fuse or fusible link
A relays 85 and 86 is just a coil of wire, so if relay is plugged in and you test wiring at the base both would show 12v with key on, that just means that coil of wire inside relay is not broken
One will be Grounded by computer and thats when the Coil of wire becomes an electro-magnet pulling the relay closed, connecting 30 and 87
This picture shows Ford numbering: https://www.ebay.com/itm/353753792835
1 and 2 are 85 and 86
3 and 4 are 30 and 87
The one in the picture also shows a diode on 1, so may not work in all bases
Larger ones are for Load, fuel pump power
With relay unplugged
Slot 85 or 86 should only have 12v with key on, the other one is the ground from computer pin 22
30 or 87 should have 12v all the time, from fuse or fusible link
A relays 85 and 86 is just a coil of wire, so if relay is plugged in and you test wiring at the base both would show 12v with key on, that just means that coil of wire inside relay is not broken
One will be Grounded by computer and thats when the Coil of wire becomes an electro-magnet pulling the relay closed, connecting 30 and 87
This picture shows Ford numbering: https://www.ebay.com/itm/353753792835
1 and 2 are 85 and 86
3 and 4 are 30 and 87
The one in the picture also shows a diode on 1, so may not work in all bases
Something is wrong then
Relay unplugged, Key OFF
One slot in base should have 12v, 3 or 4, yellow wire usually from fuse or fusible link
Key ON, a 2nd slot should now have 12v, 1 or 2
Red wire in most years, comes from EEC relay
Tan/green stripe wire is usually the ground from computer pin 22
Relay unplugged, Key OFF
One slot in base should have 12v, 3 or 4, yellow wire usually from fuse or fusible link
Key ON, a 2nd slot should now have 12v, 1 or 2
Red wire in most years, comes from EEC relay
Tan/green stripe wire is usually the ground from computer pin 22
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AlgotRanger
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Feb 26, 2025 05:20 PM



