Engine Controls - Basic Diagnostic Procedures: Diagnosis Honda Civic VI

VISUAL INSPECTION

Visually inspect all electrical wiring for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and not pinched or cut. See VACUUM DIAGRAMS article to verify routing and connections. Inspect air induction system for possible vacuum leaks.

Basic Diagnosis

Begin basic diagnosis of fuel system by determining fuel system pressure. If fuel pump fails to run, inspect power supply to PGM-FI main relay. If all power supplies are present (i.e., battery, ignition and starter switch during cranking), perform functional test of main relay. See WIRING DIAGRAMS and SYSTEM/COMPONENT TESTS articles.

Pressure Testing

1. Disconnect negative battery terminal. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-16344-S37180096532001010800000) . Remove the fuel pulsation damper (except Civic & Prelude). On Civic remove 12-mm banjo bolt. On Prelude, remove the sealing nut on fuel rail. Connect Fuel Pressure Gauge (07406-0040001 ). Reconnect negative battery terminal. Disconnect vacuum hose from fuel pressure regulator and pinch return line closed. Start engine, and read fuel pressure. If engine will not start, turn ignition on, wait for 2 seconds, turn ignition off, then on again and read fuel pressure.
2. With engine idling, reconnect vacuum hose to fuel pressure regulator and release fuel return line. Note fuel pressure. Both gauge readings should be within specification. See «REGULATED FUEL PRESSURE»(ref-16344-S06233383362001010800000) . If fuel pressure is higher than specified, check for pinched or clogged fuel return hose or defective fuel pressure regulator. If fuel pressure is lower than specified, check for clogged fuel filter, defective fuel pressure regulator or fuel line leakage.
3. Relieve fuel pressure and remove gauge. Reinstall fuel pulsation damper using NEW copper washers (except Civic & Prelude) and tighten to 16 ft. lbs. (22 N.m.). On Civic, tighten 12-mm banjo bolt to 25 ft. lbs. (33 N.m). On Prelude, tighten 12-mm sealing nut to 16 ft. lbs. (22 N.m). Start engine and check for leaks.

REGULATED FUEL PRESSURE AT IDLE

Ignition Control Module (ICM) Input Test (Civic 1.6L)

1. Turn ignition off. Remove distributor cap, rotor and leak cover (TEC). Disconnect wires from ICM. (Scheme 4)or (Scheme 5). Turn ignition on. Check for voltage between ground and Black/Yellow wire. If battery voltage exists, go to next step. If battery voltage does not exist, check Black/Yellow wire between underdash fuse/relay box and ICM. Repair wire as necessary.
2. Turn ignition on. Check for voltage between ground and Blue (2) wire (Hitachi) or White/Blue wire (TEC). (Scheme 4)or (Scheme 5). If battery voltage exists, go to next step. If battery voltage does not exist, check ignition coil. See «IGNITION COIL RESISTANCE TEST»(ref-16344-S32328022732001010800000). If ignition coil is okay, check Blue (2) wire (Hitachi) or White/Blue wire (TEC) between ignition coil and ICM. Repair as necessary.
3. Turn ignition switch off. Disconnect PCM 32-pin "A" connector. Check for continuity in Yellow/Green wire between PCM 32-pin connector terminal A20 and ICM. See WIRING DIAGRAMS. If continuity exists, go to next step. If continuity does not exist, repair open in Yellow/Green wire.
4. Check for continuity between ground and Yellow/Green wire. If continuity does not exist, go to next step. If continuity exists, repair short to ground in Yellow/Green wire.
5. Reconnect PCM 32-pin connector "A" to PCM. Check for continuity in Blue (1) wire between ICM and tachometer test connector. If continuity exists, go to next step. If continuity does not exist, repair open in Blue (1) wire.
6. Check for continuity between ground and Blue (1) wire. If continuity exists, repair short to ground in Blue (1) wire. If continuity does not exist, wiring is okay. Replace ICM.

Ignition Control Module (ICM) Input Test (CR-V 2.0L)

1. Turn ignition off. Remove distributor cap, rotor and leak cover. Disconnect wires from ICM. (Scheme 6) Turn ignition on. Check for voltage between ground and Black/Yellow wire. If battery voltage exists, go to next step. If battery voltage does not exist, check Black/Yellow wire between fuse No. 9 (15-amp) in underdash fuse/relay box and ICM. See WIRING DIAGRAMS. Repair wire as necessary.
2. Turn ignition on. Check for voltage between ground and White/Blue wire. If battery voltage exists, go to next step. If battery voltage does not exist, check ignition coil. See «IGNITION COIL RESISTANCE TEST»(ref-16344-S32328022732001010800000). Replace coil as necessary. If ignition coil is okay, check for an open in White/Blue wire between ICM and ignition coil. See WIRING DIAGRAMS.
3. Check for continuity in Blue wire between tachometer test connector and ICM. If continuity exists, go to next step. If continuity does not exist, repair open in Blue wire.
4. Check for continuity between ground and Blue wire. If continuity exists, repair short to ground in Blue wire. If continuity does not exist, wiring is okay. Replace ICM.

Ignition Control Module Input Test (Oasis & Odyssey 2.3L)

1. Turn ignition off. Remove distributor cap, rotor and leak cover. Disconnect wires from ICM. (Scheme 7) Turn ignition on. Check for voltage between ground and Black/Yellow wire. If battery voltage exists, go to next step. If battery voltage does not exist, check Black/Yellow wire between ignition switch and ICM. See WIRING DIAGRAMS. Repair wire as necessary.
2. Turn ignition on. Check for voltage between ground and White/Black wire. If battery voltage exists, go to next step. If battery voltage does not exist, check ignition coil. See «IGNITION COIL RESISTANCE TEST»(ref-16344-S32328022732001010800000). Replace coil as necessary. If ignition coil is okay, check for an open in White/Black wire between ICM and ignition coil. See WIRING DIAGRAMS.
3. Turn ignition switch off. Disconnect PCM 25-pin "B" connector. Check for continuity in Yellow/Green wire between PCM 25-pin connector terminal B13 and ICM. See WIRING DIAGRAMS. If continuity exists, go to next step. If continuity does not exist, repair open in Yellow/Green wire.
4. Check for continuity between ground and Yellow/Green wire. If continuity exists, repair short to ground in Yellow/Green wire. If continuity does not exist and all other tests are okay, replace ICM.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

1. Turn ignition off. Remove distributor cap, rotor and leak cover. Disconnect wires from ICM. (Scheme 8) Turn ignition on. Check for voltage between ground and ICM Black/Yellow wire. If battery voltage exists, go to next step. If battery voltage does not exist, check for an open in Black/Yellow wire between ignition switch and ICM.
2. Turn ignition on. Check for voltage between ground and ICM Green wire (White/Black wire on Accord F22B1 engine). (Scheme 8) If battery voltage exists, go to next step. If battery voltage does not exist, check ignition coil. See «IGNITION COIL RESISTANCE TEST»(ref-16344-S32328022732001010800000). Replace coil as necessary. If ignition coil is okay, check for an open in Green wire (White/Black wire on Accord F22B1 engine) between ICM and ignition coil.
3. Turn ignition switch off. Disconnect PCM 32-pin "A" connector. Check for continuity in Yellow/Green wire between PCM 32-pin connector terminal A20 and ICM. See WIRING DIAGRAMS. If continuity exists, go to next step. If continuity does not exist, repair open in Yellow/Green wire.
4. Check for continuity between ground and Yellow/Green wire. If continuity does not exist, go to next step. If continuity exists, repair short to ground in Yellow/Green wire.
5. Reconnect PCM 32-pin connector "A" to PCM. Disconnect instrument cluster 22-pin (16-pin on Prelude) connector. Check for continuity in Blue wire between ICM and tachometer. If continuity exists, go to next step. If continuity does not exist, repair open in Blue wire.
6. Check for continuity between ground and Blue wire. If continuity exists, repair short to ground in Blue wire. If continuity does not exist, wiring is okay. Reconnect instrument cluster connector. Replace ICM.

See also:
• ADJUSTMENTS