Honda Civic. Manual — part 688

And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 23.

NO - Replace PGM-FI main relay 2 (FUEL PUMP).

23. Turn the ignition switch OFF.
24. Reconnect ECM/PCM connector A (44P).
25. Open the SCS line with the HDS.
26. Turn the ignition switch OFF.
27. Turn the ignition switch ON (II), and measure voltage between under-dash

fuse/relay box connector F (34P) terminal No. 10 and body ground within 2
seconds.

Fig. 19: Measuring Voltage Between Fuse/Relay Box Connector F (34P)
Terminal No. 10 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Update the ECM/PCM if it does not have the latest software (see
UPDATING ECM/PCM ), or substitute a known-good ECM/PCM (see
SUBSTITUTING THE ECM/PCM ), then recheck. If the
symptom/indication goes away with a known-good ECM/PCM, replace the
original ECM/PCM (see ECM/PCM REPLACEMENT ).

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Fuel Supply System (R18A1) - Civic (Except Hybrid)

NO - Go to step 28.

28. Turn the ignition switch ON (II), and measure voltage between under-dash

fuse/relay box connector F (34P) terminal No. 10 and body ground after 2
seconds.

Fig. 20: Measuring Voltage Between Fuse/Relay Box Connector F
Terminal No. 10 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 29.

NO - If needed, replace the under-dash fuse/relay box (see REMOVAL AND
INSTALLATION ), then go to step 29.

29. Turn the ignition switch OFF.
30. Remove the rear seat cushion (see REAR SEAT

REMOVAL/INSTALLATION ).

31. Remove the rear floor upper cross-member, then remove the access panel from

the floor (see FUEL TANK UNIT REMOVAL/INSTALLATION ).

32. Turn the ignition switch ON (II), and measure voltage between fuel tank unit

4P connector terminal No. 2 and body ground within 2 seconds.

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Fuel Supply System (R18A1) - Civic (Except Hybrid)

Fig. 21: Measuring Voltage Between Fuel Tank Unit 4P Connector
Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Go to step 37.

NO - Go to step 33.

33. Turn the ignition switch OFF.
34. Remove PGM-FI main relay 2 (FUEL PUMP).
35. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminals No. 1

and No. 2 with a jumper wire.

Fig. 22: Connecting PGM-FI Main Relay 4P Connector Terminals No. 1
And 2 With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.

36. Turn the ignition switch ON (II), and measure voltage between fuel tank unit

4P connector terminal No. 2 and body ground within 2 seconds.

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Fuel Supply System (R18A1) - Civic (Except Hybrid)

Fig. 23: Measuring Voltage Between Fuel Tank Unit 4P Connector
Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES - Replace PGM-FI main relay 2 (FUEL PUMP).

NO - Repair open in the wire between PGM-FI main relay 2 (FUEL PUMP)
and the fuel tank unit 4P connector.

37. Turn the ignition switch OFF.
38. Check for continuity between fuel tank unit 4P connector terminal No. 4 and

body ground.

Fig. 24: Checking Continuity Between Fuel Tank Unit 4P Connector
Terminal No. 4 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

2008 Honda Civic GX

2006-08 ENGINE PERFORMANCE Fuel Supply System (R18A1) - Civic (Except Hybrid)