Civic L4-1.8L CNG (2008)
Is there continuity?
YES - 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 (A37) and DLC terminal No. 14.
35. Try to start the engine.
Does the engine start and idle smoothly?
YES - Go to F-CAN circuit troubleshooting. See: Testing and Inspection/Component Tests and General Diagnostics/F-CAN Circuit
Troubleshooting
NO - Go to step 36.
36. Turn the ignition switch OFF.
37. Check the No. 2 IG MAIN (50 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Repair open in the wire between the No. 2 IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 38.
NO - Repair short in the wire between the No. 2 IG MAIN (50 A) fuse and the under-hood fuse/relay box. Also replace the No. 2 IG MAIN (50 A
) fuse.
38. Inspect the No. 19 FI MAIN (15 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Go to step 45.
NO - Go to step 39.
39. Remove the blown No. 19 FI MAIN (15 A) fuse from the under-hood fuse/relay box.
40. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
41. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 3 individually.