Fuel Cap Warning Message System Troubleshooting

Special Tools Required 

• Vacuum pump/gauge, 0-30 in Hg, Snap-on YA4000A or equivalent, commercially available
• Vacuum/pressure gauge, 0-4 in Hg 07JAZ-001000B

Do this procedure if the fuel cap warning message comes on frequently, or if the message does not go off after the fuel fill cap is tightened and the vehicle is driven several days

1. Check the fuel fill cap (the cap must say TIGHTEN TO CLICK) It should turn 1/4 after it's tight, then it clicks

   Is the correct fuel fill cap installed and properly tightened? 

   YES  -Go to step 2

   NO  -Replace or tighten the cap, then go to step  13

2. Check the fuel fill cap seal (A) and the fuel fill pipe mating surface (B) Verify that the fuel fill cap tether cord (C) is not caught under the cap
   Fig 1: Identifying Fuel Fill Cap Seal And Fuel Fill Pipe Mating Surface

   Courtesy of AMERICAN HONDA MOTOR CO., INC.

   Is the fuel fill cap seal missing or damaged, is the fuel fill pipe damaged, or is the tether cord caught under the cap? 

   YES  -Replace the fuel fill cap or the fuel fill pipe, then go to step  13

   NO  -Go to step 3

3. Reinstall and tighten the fuel fill cap
4. Clear the DTC with the HDS
5. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in 4th) until the radiator fan comes on, then let it idle for 1 minute
6. Test drive at 45 mph (72 km/h) for 1 minute or more

   Does the fuel fill cap warning message come on? 

   YES  -Go to step 7

   NO  -Intermittent failure, the system is OK at this time

7. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
8. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B) in the engine compartment, then connect a T-fitting (C) from the vacuum gauge, and connect the vacuum pump/gauge 0-30 in Hg, to the EVAP canister purge valve as shown
   Fig 2: Connecting T-Fitting From Vacuum Gauge

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
9. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
10. Apply about 2 kPa (0 6 in Hg, 15 mmHg) of vacuum to the hose
11. Select the EVAP PCS ON in the INSPECTION MENU with the HDS

    Does the vacuum release immediately? 

    YES  -Check for a blockage in the vacuum hose/line between the EVAP canister purge valve and the EVAP canister, then go to step 12

    NO  -Replace the EVAP canister purge valve (see EVAP CANISTER FILTER REPLACEMENT ), then go to step 12

12. Install the parts in the reverse order of removal
13. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
14. Reset the PCM with the HDS
15. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE )
16. Test-drive at 45 mph (72 km/h) for 1 minute or more

    Does the fuel cap warning message come on? 

    YES  -Go to step  1 and recheck

    NO  -Troubleshooting is complete