I am going to be installing a fuel pump cutoff switch tomorrow and was told that the switch goes on the black lead to the PGM-FI Main Relay, not black/green.
The black is the ground, [constant] for the injector power relays coil, the injector power relay supplies switched power to not only the injectors, but also switched power for the ECU/ECM a few sensors, and the the fuel pump power relays coil.
Is that correct? and the PGM-FI main relay is in the fuse box under the hood correct and I tap into the wire that goes to that correct?
Yes, install the switch on the black lead, it is the ground for the coil on the injector relay, it is “low current” no more then 250mA so only a small 1A switch is needed, but be careful if there are two black leads going to the same terminal, [daisy chain], they must stay together on one side of switch.
The PGM-FI Main Relay is located under the drives side dash, to the left of the steering column… http://www.tegger.com/hondafaq/mainrelay.html this is how to repair the PGM-FI Main Relay but the first one it shows is a G2.:bowthank:94
On some Honda/Acura there are two black leads on the same terminal, [PGM-FI Main Relay ground] one of the black leads is the ground, [“ground in”, from a chassis ground point] the other black lead is a ground for something else in the dash, [“ground out” ,possibly another relay, not sure, never bothered to find out] it is called daisy chaining, because you do not want the switch to also “kill” whatever that lead is grounding you must keep the two black leads together, [just like they are in the PGM-FI Main Relay plug] so the daisy chain is not broken, so when, [and if there are two leads] you cut the leads to install the switch, both the ground “in” and ground “out” must be kept together and connected to one side of the switch.:whew:94