Dan from Vehix411.
Got a ’99 Honda Civic. The problem over here is the car would turn over
but not start. This is a common problem on the Acura and Hondas. The problem is the MFI/PGI relay, the main relay goes bad often on these cars and it would not give out power to either the fuel pump or the engine power source. So on the Civics, I’ll show you where the relay is located. Open the passenger door and remove the glove box. All this is glove box, remove it and they just melt on there. This is the relay and they call it relay assembly main. And you can test these
or just buy one. Whatever you want to do. But to test it, you need is wiring diagram. Which I got one right here. And it’s pretty simple. What you gotta do is check if it gives out the yellow and green wire. This is the wire right here. It’s this corner one right here, yellow and green. It’s right here, yellow and green. When you put the ignition on, just get a tester right here. Just like any light tester. Put it on ground. And what you do is…it’s pretty hard to do it with one hand. Alright, what you do is, there’s two yellow and green ones. So the one that’s on the
very edge, on the corner. That the one you’re gonna test. And what you do is plug it in there. Put the key in the ignition. Don’t start the car, just put the ignition on.
And once you put the ignition on, the light should come on. Which right here, this red light comes on. Once you put the ignition off, it comes off. Come on, comes off, you can hear it clicking. So that’s one. There’s two relays inside. So that’s one of the power source. The other power source you gotta check is the yellow and black. Which is this one right here. So all you do, put them on yellow and black
and the relay lights up, I mean, the light lights up. Testing light, so. Ignition on, light lights up. So this relay is good. The bad relay, either the yellow and black
wouldn’t light up. Or yellow and green. If they don’t light up, and you got power coming to it, there’s two powers that are supposed to come through it. And if you got power coming through it, then just replace the MFI/PGI relay. That’s how you diagnose a no start condition on a Honda and Acura before replacing any other parts.