It is very necessary to release the fuel pressure before open any fuel hose and parts.So here i write this instruction on how to make fuel pump off before fuel replacement by Launch X431.More Launch X431 Training article,please check here:Launch X431 user guide
Procedures:
Connect Launch X431 to Honda vehicle.
First step,check and make sure no trouble code otherwise the actuation test will unsuccessful.
Then select [Actuation Test]
Select [Fuel Pump Off],this function manually stop the fuel pump.
Start the engine
Please ensure the gear shift is in Neutral
Parking Brake is Applied
Do not press the throttle pedal
The condition of stop the fuel pump:Engine speed <1000RPM
We just wait for engine speed droop
The fuel pressure has been relieved
Turn the ignition switch off
And please not:the fuel pressure will be restored if the ignition is switch on.
Now you can disconnect Launch X431 to start fuel replacement work
Open the fuel hose with minimum leak
Install all parts back on your vehicle,turn ignition on and start.
All back to normal.