EVAP Bypass Solenoid Valve Test

11. Disconnect both vacuum hoses from the EVAP two way valve (A), and connect a commercially available vacuum pump/gauge, 0-30 in.Hg, to the canister port on the two way valve.

Fig 1: Disconnecting Both Vacuum Hoses From EVAP Two Way Valve
Courtesy of AMERICAN HONDA MOTOR CO., INC.
12. Turn the EVAP bypass solenoid valve ON with the HDS, or connect ECM connector terminal A3 to body ground with a jumper wire.

Fig 2: Identifying ECM Connector A (32P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
13. Turn the ignition switch ON (II).
14. Apply vacuum to the hose.
Does the valve hold vacuum?
1. YES - Go to step 15.
2. NO - Go to step 20.
16. Turn the ignition switch OFF.
17. Disconnect the EVAP bypass solenoid valve 2P connector.
Check for continuity between EVAP bypass solenoid valve 2P connector terminal No. 2 and body ground.

Fig 3: Checking For Continuity Between EVAP Bypass Solenoid Valve 2P Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 18.
2. NO - Repair open in the wire between the EVAP bypass solenoid valve and the ECM (A3).
18. Turn the ignition switch ON (II).
19. Measure voltage between EVAP bypass solenoid valve 2P connector terminal No. 1 and body ground.

Fig 4: Measuring Voltage Between EVAP Bypass Solenoid Valve 2P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Replace the EVAP bypass solenoid valve (A) and the O-rings (B).
2. NO - Repair open in the wire between the EVAP bypass solenoid valve and the No. 6 ACG (15 A) fuse.
20. Plug the upper port (A) of the EVAP two way valve.

Fig 5: Plugging Upper Port Of EVAP Two Way Valve
Courtesy of AMERICAN HONDA MOTOR CO., INC.
21. While monitoring FTP sensor voltage with the HDS, or measuring the voltage between ECM connector terminals A29 and C18, slowly pump the vacuum pump/gauge until the voltage drops to about 1.5 V.

Fig 6: Measuring Voltage Between ECM Connector Terminals A29 And C18
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Does the voltage drop to 1.5 V and hold for at least 20 seconds?
1. YES - The EVAP bypass solenoid valve/EVAP two way valve is OK. Go to step 22.
2. NO - Repair leak from the EVAP bypass solenoid valve, EVAP two way valve, FTP sensor, or O-rings.