Service Bulletin
October 4, 2016

15-021
04972 Version 2

Fuel Gauge Does Not Work and the Low Fuel Indicator Blinks with Fuel
in the Tank
(Supersedes 15-021, dated March 31, 2015, to revise the information highlighted in yellow)
AFFECTED VEHICLES
Year
Model
2001–15
Civic CNG

VIN Range
ALL

REVISION SUMMARY
Under TROUBLESHOOTING PROCEDURE, steps 3 and 4 were updated.
SYMPTOM
The fuel gauge does not work and the low fuel indicator blinks with fuel in the tank.
TROUBLESHOOTING PROCEDURE
NOTE:
• If the PCM has any DTCs, do the DTC troubleshooting in the electronic service manual first before continuing.
• See the electronic service manual for specific procedures called out in this bulletin.
1. Do a battery cable reset. For details, see ServiceNews article “Try a Battery Cable Reset for Those Odd Electrical
Problems,” posted in January 2012. You can also see this demonstrated in the Tech2Tech video “Try a Battery
Cable Reset!”
Does the problem go away?
YES – Check for contamination in both fuel filters A and B and replace if needed. If the problem happens again,
replace the thermovalve. If the problem persists, replace fuel pressure regulator P1.
NO – Go to step 2.
2. Close the manual shutoff valve.
3. (2001–05 models): Remove PGM-FI main relay 2.
4. (2006–15 models): Remove the shut-off solenoid valve relay.
5. Turn the ignition to ON.

CUSTOMER INFORMATION: The information in this bulletin is intended for use only by skilled technicians who have the proper tools,
equipment, and training to correctly and safely maintain your vehicle. These procedures should not be attempted by “do-it-yourselfers,” and you
should not assume this bulletin applies to your vehicle, or that your vehicle has the condition described. To determine whether this information
applies, contact an authorized Honda automobile dealer.

© 2016 American Honda Motor Co., Inc. – All Rights Reserved

Page 1 of 3

6. Measure the voltage between the fuel pressure regulator terminal No. 1 and body ground.

Is there more than 3 volts?
YES – Go to step 7.
NO – Substitute a known-good PCM, then recheck. If the symptom goes away, replace the original PCM.
7. Disconnect the fuel temperature sensor on the fuel rail.
8. With the vehicle in a well-ventilated area or outside, loosen the sensor until gas escapes. After the gas has vented,
go to step 9.
NOTE: When venting the sensor, the O-ring must be replaced.
9. Measure the voltage between the fuel pressure regulator terminal No. 1 and body ground.

Is there more than 3 volts?
YES – Go to step 10.
NO – Replace fuel pressure regulator P1.
10. Turn the ignition to OFF.
11. Unplug the fuel pressure regulator switch 2-pin connector.
12. Check for continuity between terminal No. 2 and body ground on the connector side.

Is there continuity?
YES – Go to step 13.
NO – Repair an open in the wire between the fuel pressure regulator switch and G201 (2001–05 models) and G401
(2006–15 models).

Page 2 of 3

13. Measure the voltage between terminal No. 1 and body ground on the connector side.

Is there more than 3 volts?
YES – Go to step 14.
NO – Repair an open in the wire between the fuel pressure regulator switch and PCM connector terminal E28
(2001–05 models) A-41 (2006-11 models) A-23 (2012–15 models).
14. Replace fuel pressure regulator P1, and recheck.
Does the low fuel indicator blink?
YES – Do a fuel leak inspection. If there is no leak, substitute a known-good PCM, then recheck. If the symptom
goes way, replace the original PCM.
NO – No further action is needed. Return the vehicle to your customer.
END

Page 3 of 3