Fuel Cap Warning Message System Troubleshooting

Special Tools Required 

• Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B
• Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available

When the fuel cap warning message does not go off after fuel cap tightened, or the message turned on frequently, do this troubleshooting procedure.

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, Uel Fill Pipe Mating Surface And Fuel Fill Cap Tether Cord

   Courtesy of AMERICAN HONDA MOTOR CO., INC.

   Is the fuel fill cap seal missing or damaged, is the fuel HI 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 (in P or N) 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 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).
8. Remove the intake air duct (air flow tube) (see step 6 under REMOVAL ).
9. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B) in the engine compartment, and connect a T-fitting (C), a vacuum gauge, and a vacuum pump/gauge, 0-30 inHg, to the EVAP canister purge valve as shown.
   Fig 2: Connecting T-Fitting, Vacuum Gauge And Vacuum Pump/Gauge To EVAP Canister Purge Valve

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
10. Turn the ignition switch to ON (II).
11. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose.
12. 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 between the EVAP canister purge valve and the EVAP canister, then go to step 13.

    NO  -Replace the EVAP canister purge valve (see EVAP CANISTER VENT SHUT VALVE REPLACEMENT ), then go to step 13.

13. Install the parts in the reverse order of removal.
14. Turn the ignition switch to ON (II).
15. Reset the PCM with the HDS.
16. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
17. Start the engine. Hold the engine speed 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle for 1 minute.
18. 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.