Main relay problems
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Main relay problems
I have a 1986 accord LXi. What are the symptoms of a bad main relay. Should the red light on the dash be lit when the key is turned to the on postion before turning over the starter. It turns over and has fuel pressure. The plugs seem to firing too. Is it true that if the relay is out it won't start ? Does it still turn over though ? Any info would be great.
Thanks !
Thanks !
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What red light? The check-engine light should come on when you turn the key on & don't start. (Along with the alternator & oil lights.)
The main relay switches power to the fuel pump & the ECU. So if it's bad, the ECU doesn't even know you've turned on the car.
The main relay switches power to the fuel pump & the ECU. So if it's bad, the ECU doesn't even know you've turned on the car.
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PGM-EFI Light
Top left corner of the idiot lights on the dash. They have a little symbol on it that looks like a computer chip. It is actually my sons car. he thinks it came on before , but now it doesn't.
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Actually, '86 is a bit old for my personal Honda experience... I'm not sure what shape/color that light would be. It seems like all cars always have at least some kind of bulb-check function when you first turn the key. If it was simply a burned-out bulb it would still start.
Flaky main relays are sorta common among Hondas anyway. The starter would still work just fine, cranking the engine over. The 'main relay' is just a couple relays together in the same case. Typically one gives power to the fuel pump, the other to the EFI system.
I hope someone with an '86 helps out... But the main relay is usually located up above the left kick panel. You might want to listen for it clicking or check it with a multi-meter.
Flaky main relays are sorta common among Hondas anyway. The starter would still work just fine, cranking the engine over. The 'main relay' is just a couple relays together in the same case. Typically one gives power to the fuel pump, the other to the EFI system.
I hope someone with an '86 helps out... But the main relay is usually located up above the left kick panel. You might want to listen for it clicking or check it with a multi-meter.
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From: PA
If you've got a soldering iron, you can take the cover off of the main relay and resolder all of the joints. These relays typically fail because of a cold (sometimes called dry) joint which means that there is a crack in the solder. The relays are over $50 new and you can resolder one in about 5-10 minutes.
Before you get out the soldering iron, however, you can test the relay using the procedures outlined in the service manual. It involves applying 12V power to specified connection tabs and checking for continuity between others as the relays are activated.
Before you get out the soldering iron, however, you can test the relay using the procedures outlined in the service manual. It involves applying 12V power to specified connection tabs and checking for continuity between others as the relays are activated.