Civic L4-1.8L CNG (2008)
Is there continuity?
YES - Test PGM-FI main relay 1 . If the relay is OK, update the PCM if it does not have the latest software , or substitute a known-good PCM ,
then recheck. If the symptom/indication goes away with a known- good PCM, replace the original PCM.
NO - Repair open in the wire between the PCM (A6) and PGM-FI main relay 1.
62. Turn the ignition switch OFF.
63. Remove PGM-FI main relay 1(C) from the under- hood fuse/relay box.
64. Measure voltage between PGM-FI main relay 1 4P connector terminal No. land body ground.
Is there battery voltage?
YES - Go to step 65.
NO - Replace the under-hood fuse/relay box,
65. Check for continuity between PGM-FI main relay 1 4P connector terminal No.2 and PCM connector terminal A8.