1996 Accord Main Relay Ground
Thread Starter
Joined: Aug 2012
Posts: 10
I won a bid for a ECM on ebay. But I just noticed it was for a manual transmission and I have an automatic. (Stupid me, but luckily it was only $10) Would it be ok to test with to see if it solves my problem? Meaning just to start the car, not actually drive it.
Last edited by snerty32; Aug 23, 2012 at 08:24 PM.
Thread Starter
Joined: Aug 2012
Posts: 10
Im still waiting for the ECM I bought, but yesterday the car started every single time just as if nothing was wrong, all day long.
Today wont start at all again. The green light never comes on around D4 nor does the fuel prime. I took the master relay out and re-soldered all the joints again, and tested it using the relay test procedure and all is working perfect with the relay.
My question.... does the Master Relay tell the Fuel pump to prime without interaction of the ECM? Or is the ECM involved somehow?
What is the route it takes to start? Does it go from Switch > Master Relay> Fuel Pump > ECM?
Today wont start at all again. The green light never comes on around D4 nor does the fuel prime. I took the master relay out and re-soldered all the joints again, and tested it using the relay test procedure and all is working perfect with the relay.
My question.... does the Master Relay tell the Fuel pump to prime without interaction of the ECM? Or is the ECM involved somehow?
What is the route it takes to start? Does it go from Switch > Master Relay> Fuel Pump > ECM?
Super Moderator
Joined: Sep 2006
Posts: 16,331
From: Houston, TX
When you turn on or off a light switch, physically lifting the switch is the signal.
A relay is simply a switch, but the signal to turn on/off the circuit is an electrical signal. Hondas typically turn on/off a relay providing/removing ground. Think of it as two switches linked together. When you turn on/off one switch, the other one turns on/off.
For the MFR, the power source for the signal and the primary side is the ignition switch.
The ground is provided/removed by the ECU. When the ECU grounds the main relay, the primary side supplies power to the fuel pump.
I hope this makes sense.
A relay is simply a switch, but the signal to turn on/off the circuit is an electrical signal. Hondas typically turn on/off a relay providing/removing ground. Think of it as two switches linked together. When you turn on/off one switch, the other one turns on/off.
For the MFR, the power source for the signal and the primary side is the ignition switch.
The ground is provided/removed by the ECU. When the ECU grounds the main relay, the primary side supplies power to the fuel pump.
I hope this makes sense.
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Joined: Oct 2010
Posts: 7,099
From: United States