How do u change the fuel pump main relay switch on a 99 Honda Accord?

I believe you just unplug it and plug in a new one.
Here is some good info for Hondas:
https://www.askmehelpdesk.com/cars-t...les-46563.html
If you have not unplugged it, how do you know its bad?
Relay coil gets positive when ignition switched on, and some need to be cranking, the negative to the Fuel coil comes from the ICM. Plus you need 12volts to provide power to the relay contact, a jumper at relay socket will verify fuel pump is good.
You can also pull and test relay, apply 12 volts to coil, you should have continuity on the contacts.

It's located left of the steering column. Turning the ignition key on and off will help you locate the main relay, by allowing you to hear and feel it "click." Main relays often have 7 wires going to them.

After recording any radio codes, disconnect the negative battery cable, remove the mounting bolt to the relay, and ease the relay out. Using a large flat blade screwdriver, carefully separate the female connector from the old relay. Install the new relay and button things up.

You may find reading the link below worthwhile:

https://www.askmehelpdesk.com/cars-t...ml#post1245523


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