Wiring in 5 prong relay for fuel pump for a 1990 lx
- Thread starter Zephyr130
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do I need to lube this area?
One of our members just went through a fpr wiring nightmare, his thread may help you as there are several illustrations from magic books
Pay attention because wire colors and relay location changed around 90-1, this is noted in the thread.
Pay attention because wire colors and relay location changed around 90-1, this is noted in the thread.
Thank you everyone for the help, i knew in late 90 or late 91 they changed the relay location from under the driver's seat ( mine is still under the seat, the car was built before April of 90 as It has one of the 20 year anniversary badges) its also a thunderbird turbo coupe swap car but the cabin wiring is untouched, ill be reading those articles everyone had sent and seeing what I can find out, I know the pnk/blk wire is back to the fuel pump im not sure what the other 3 are for and I don't want to wire incorrectly and burn my car down, again thank you everyone
Read through those threads and linked articles here, what I'm looking for is what the specific wires do off my connector because I know I can fry something If i do this wrong, only reason im swapping to a 5 prong is im working on a tight budget and it's the kind of relay I have around vs spending 40$ on a new relay I thought I had attached the connector and wire colors to my original post but here's an attachment with them
I'll get you the correct wiring diagram later on, but this is pretty simple.
2 wires are your coil activation wires, and 2 wires are your main power, and then power out to the pump. The normally closed terminal remains not connected.
Are you using a standard 5-prong non-ford relay? If so, 85 and 86 are your coil. 30 is main power in from the fusible link, and 87 and 87A would be your output wires. 87 is normally open and thats the wire you would use to power the pump. 87a stays unconnected.
I'll check later what wire colors were used in 1990 to make sure i give you the right info. Check back later tonight
2 wires are your coil activation wires, and 2 wires are your main power, and then power out to the pump. The normally closed terminal remains not connected.
Are you using a standard 5-prong non-ford relay? If so, 85 and 86 are your coil. 30 is main power in from the fusible link, and 87 and 87A would be your output wires. 87 is normally open and thats the wire you would use to power the pump. 87a stays unconnected.
I'll check later what wire colors were used in 1990 to make sure i give you the right info. Check back later tonight
Thank you, Ill be back later on, I had more or less figured out the relay side of things just not the harness area of the car, yes I'm swapping the ford specific relay to a standard 5 prong, if I wasn't on such a tight budget I'd just buy a new relay but this is my option at current, thank you again for taking the time to find the right information for me
SO 1990 is different from the 1991 diagram above.
Red/Black - 12V key on - Pin 85
Tan/Light Green - ECU controlled ground - Pin 86
Orange/Light Blue - 12V key on from fusible link - Pin 30
Pink/Black - Feed out to pump - Pin 87
Pin 87A stays empty as this is normally closed. That would be pin 5 on the wiring diagram below which is open
Red/Black - 12V key on - Pin 85
Tan/Light Green - ECU controlled ground - Pin 86
Orange/Light Blue - 12V key on from fusible link - Pin 30
Pink/Black - Feed out to pump - Pin 87
Pin 87A stays empty as this is normally closed. That would be pin 5 on the wiring diagram below which is open
I have a pink and black and a red and black but my other 2 wires are tan and green and light green, would the pink and black and red and black correspond with the ones on this diagram?SO 1990 is different from the 1991 diagram above.
Red/Black - 12V key on - Pin 85
Tan/Light Green - ECU controlled ground - Pin 86
Orange/Light Blue - 12V key on from fusible link - Pin 30
Pink/Black - Feed out to pump - Pin 87
Pin 87A stays empty as this is normally closed. That would be pin 5 on the wiring diagram below which is open
Typical Ford changing wire colors. The fuel pump relay wire colors seem to change almost yearly.
Have to do it the old fashioned way. 2 wire pairs. Solenoid power/ground and main power and feed to pump.
Check for power with key OFF. Only one wire will have 12v of the three. It’s marked in the diagram as HOT AT ALL TIMES. That’s your fuel pump feed wire. (Wire 238 in the diagram) this wire goes to pin 30 on your relay. It’s most likely the orange/blue wire in your case.
Next, turn the key to on. The red/black wire should then have 12v. Wire 356. This is pin 85 on your relay.
The pink/black should be your wire out to your pump. You can verify by looking at your fuel pump wiring, or pin 19 on the ECU to see if pink/black is also there. This is 87 on your relay.
The last wire should be what goes to ECU pin 22. I assume it’s tan. This would be pin 86 on your relay. If you look at the test plug connector under the hood, there should be a matching wire on the connector. If you have a multimeter, you can check continuity to the tan wire in the eec test plug to the fuel pump relay harness.
Always verify your wires before hooking power up.
Have to do it the old fashioned way. 2 wire pairs. Solenoid power/ground and main power and feed to pump.
Check for power with key OFF. Only one wire will have 12v of the three. It’s marked in the diagram as HOT AT ALL TIMES. That’s your fuel pump feed wire. (Wire 238 in the diagram) this wire goes to pin 30 on your relay. It’s most likely the orange/blue wire in your case.
Next, turn the key to on. The red/black wire should then have 12v. Wire 356. This is pin 85 on your relay.
The pink/black should be your wire out to your pump. You can verify by looking at your fuel pump wiring, or pin 19 on the ECU to see if pink/black is also there. This is 87 on your relay.
The last wire should be what goes to ECU pin 22. I assume it’s tan. This would be pin 86 on your relay. If you look at the test plug connector under the hood, there should be a matching wire on the connector. If you have a multimeter, you can check continuity to the tan wire in the eec test plug to the fuel pump relay harness.
Always verify your wires before hooking power up.
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Just a question... why are you worried about the wires and where they go? Are you re-wiring the car? If it is just not trusting the relay, relays are wired the same, just plug it in (assuming you are not dealing with cut wires and trying to reconnect everything).
If changing the relay because fuel pump not working, don't forget to check the connectors in the driver kick panel. I have a 90 GT, built on last day of production in July 90 (I assume based on VIN number). I fought with intermittent fuel pump kicking out. I changed relay twice with no real improvement. Turned out to be a bad connection in one of the connectors behind the kick panel.
If changing the relay because fuel pump not working, don't forget to check the connectors in the driver kick panel. I have a 90 GT, built on last day of production in July 90 (I assume based on VIN number). I fought with intermittent fuel pump kicking out. I changed relay twice with no real improvement. Turned out to be a bad connection in one of the connectors behind the kick panel.
I have no relay to start with right now thats why im wiring one in and then hoping my pump hasn't gone bad from sitting for as long as it has, the ford one is nowhere in the parts I got for the car to put it back together, it's a 90 lx with an 88 turbocoupe swap and im not sure how far back into the wiring they would have molested, the cabin wiring looks normal, but it runs off an LA3 turbocoupe ecm not the stock 2.3L ecm, I was told and basically hoping this would be a throw it together and finally have the chance to drive a foxbody but it's turning into a wiring nightmare, I have no experience in wiring and thats kinda where my downfall is, I'm going through and seeing what wires I can find today with 12v and 12v key on but I still have to figure out my other 2 wires as they don't match the 1990 wiring harness colours and I don't wanna cross things and burn up my ecm
If you are concerned about damaging the ECU, just unplug it.
You'll still have power on wire 238, but you'll lose it on wire 366 (red/black) with the ecu disconnected. But, you can just test continuity back to the ECU connectors at pin 57 and 22 to confirm which wire is your relay solenoid feed, and which is the switched ground back to the ECU.
I don't think there is much risk to damage the ECU, but you are correct to play it safe.
You'll still have power on wire 238, but you'll lose it on wire 366 (red/black) with the ecu disconnected. But, you can just test continuity back to the ECU connectors at pin 57 and 22 to confirm which wire is your relay solenoid feed, and which is the switched ground back to the ECU.
I don't think there is much risk to damage the ECU, but you are correct to play it safe.
To test continuity what would I have to do? I have the ecu unplugged at current and I'm just gonna tough it out with testing my connector today and seeing whats what with power and what colours at the inertia switch and at the ecu hookup, im assuming I'll see the tan and light green wire at the connector for the ecu
Your meter should have a continuity feature that looks like the symbol i've highlighted. If you touch the two leads together, the meter should make an audible sound. If your meter doesn't have this, you can use the Ohmmeter setting (looks like a horseshoe) and touch the leads together You should see the display chang and settle out at zero.
To test continity. Just touch one lead to one wire, and the other lead to the suspected other end. It will either ring or the display will change to 0 if using Ohms
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