Engine Controls - Tests W/codes: Other Honda Civic VI

CIRCUIT TESTS

Note. Before performing any diagnostic test, refer to TESTS W/CODES - INTRODUCTION article for diagnostic system functions and system diagnostic procedures.

Note. Models equipped with a manual transmission use an Engine Control Module (ECM). Models equipped with an automatic transmission use a Powertrain Control Module (PCM). Because the operation of these components is similar, ECM will be referred to as a PCM.

Note. When there is no DTC stored, MIL will stay on if the SCS service connector is connected and ignition switch is on.

When directed by testing procedure to install test equipment, see TEST EQUIPMENT in TESTS W/CODES - INTRODUCTION article.

Malfunction Indicator Light (MIL) Never Comes On, Even For 2 Seconds, After Ignition Is Turned On

1. Turn ignition on. If low oil pressure light is on, go to next step. If light is not on, replace No. 25 METER (7.5-amp) fuse. Repair short or open in Yellow wire between fuse and gauge assembly. See «WIRING DIAGRAMS»(ref-16355) article.
2. Try to start engine. If engine starts, go to next step. If engine does not start, turn ignition on. Measure voltage between ground and PCM 32-pin connector "A" terminal A10 (Black wire) and terminal A23 (Black wire), individually. see scheme 1 If one volt or more exists, repair open in Black wire(s) between PCM and ground connection G101, located at thermostat housing. If less than one volt exists, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
3. Turn ignition off. Using backprobe set, connect a fused jumper wire between ground and PCM 32-pin connector "A" terminal A18 (Green/Orange wire). see scheme 1 Turn ignition on. If MIL comes on, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If MIL does not come on, replace MIL bulb and/or repair open in Green/Orange wire between PCM connector and gauge assembly. See «WIRING DIAGRAMS»(ref-16355) article.

Malfunction Indicator Light (MIL) Stays On Or Comes On After 2 Seconds

1. If symptom is intermittent, check for: A loose No. 44 FI E/M (15-amp) fuse located in underhood fuse/relay box. A loose No. 13 FUEL PUMP (15-amp) fuse located in underdash fuse/relay box. An intermittent short in Brown wire between PCM 31-pin connector "C" terminal C7 and service check connector. see scheme 3 See «WIRING DIAGRAMS»(ref-16355) article. An intermittent short in Green/Orange wire between PCM 32-pin connector "A" terminal A18 and gauge assembly. see scheme 1 See «WIRING DIAGRAMS»(ref-16355) article. An intermittent short in Yellow/Red wire between PCM 16-pin connector "D" terminal D4 and MAP sensor. see scheme 4 See «WIRING DIAGRAMS»(ref-16355) article. An intermittent short in Yellow/Blue wire between PCM 16-pin connector "D" terminal D10, TP sensor, EGR valve lift sensor (if equipped) and/or fuel tank pressure sensor. A faulty PGM-FI main relay. Perform repairs as necessary and recheck MIL operation. If no problems are found, go to next step.
2. Connect OBD-II scan tool to DLC connector. Turn ignition on. Read Diagnostic Trouble Codes (DTCs). See «RETRIEVING CODES»(ref-16345-S38702527312000122900000) in TESTS W/CODES - INTRODUCTION article. If DTCs are present, go to «DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION»(ref-16347-S10807603222002082600000) table. After identifying DTC, go to DTC test. If DTCs are not present, go to next step.
3. Turn ignition off. Connect SCS service connector to service check connector. See SELF-DIAGNOSTIC INTRODUCTION article. Turn ignition on. If DTCs are present, go to «DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION»(ref-16347-S10807603222002082600000) table. If DTCs are not present using MIL, go to next step. If DTCs are present using MIL, repair open or short in Light Blue wire between PCM 31-pin connector "C" terminal C8 and DLC terminal No. 15. see scheme 1and see scheme 5. Recheck for DTCs. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION table. After identifying DTC, go to DTC test.
4. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step 7).
5. Turn ignition off. Disconnect SCS service connector. Turn ignition on. Measure voltage between ground and PCM 31-pin connector "C" terminal C7 (Brown wire). see scheme 3 If about 5.0 volts exists, go to next step. If about 5.0 volts does not exist, repair short to ground in Brown wire between PCM and service check connector. See «WIRING DIAGRAMS»(ref-16355) article.
6. Turn ignition off. Disconnect PCM 32-pin connector "A". Turn ignition on. If MIL is on, repair short to ground in Green/Orange wire between PCM 32-pin connector "C" terminal A18 and MIL. see scheme 1and see scheme 5. See «WIRING DIAGRAMS»(ref-16355) article. If MIL is not on, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
7. Inspect No. 44 FI E/M (15-amp) fuse located in underhood fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in White/Black wire between fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-16355) article. Replace No. 44 FI E/M (15-amp) fuse.
8. Inspect No. 13 FUEL PUMP (15-amp) fuse, located in underdash fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in Yellow/Green wire between fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-16355) article. Replace No. 13 FUEL PUMP (15-amp) fuse.
9. Turn ignition on. While observing MIL, disconnect 3-pin connector from Manifold Absolute Pressure (MAP) sensor, Throttle Position (TP) sensor, EGR valve lift sensor and Fuel Tank Pressure (FTP) sensor (if equipped), one at a time. If MIL does not go off, go to next step. If MIL goes off, replace sensor that caused MIL to go off.
10. Turn ignition off. Disconnect PCM 16-pin connector "D". Check for continuity between ground and PCM 16-pin connector "D" terminal D4 (Yellow/Red wire) and terminal D10 (Yellow/Blue wire), individually. see scheme 4 If continuity does not exist, go to next step. If continuity exists, repair short to ground in Yellow/Red wire between PCM 16-pin connector "D" terminal D4 and MAP sensor, or Yellow/Blue wire between PCM connector terminal D10 and TP sensor, EGR valve lift sensor or FTP sensor (if equipped). See «WIRING DIAGRAMS»(ref-16355) article.
11. Turn ignition off. Disconnect fuel injectors connectors and IAC valve connector. Reconnect PCM 16-pin connector "D". Turn ignition on. Measure voltage between ground and PCM 32-pin connector "A" terminal A11 (Yellow/Black wire) and terminal A24 (Yellow/Black wire), individually. see scheme 1 If battery voltage exists, go to next step. If battery voltage does not exist, repair open in suspect wire(s) between PCM 32-pin connector "A" and PGM-FI main relay. If wires are okay, check for poor connections or loose wires at PGM-FI main relay. See «WIRING DIAGRAMS»(ref-16355) article. If connections and wires are okay, check PGM-FI main relay. See «SYSTEM/COMPONENT TESTS»(ref-16351) article.
12. Turn ignition off and reconnect all sensor connectors. Reconnect PCM 16-pin connector "D". Turn ignition on. Measure voltage between ground and PCM 32-pin connector "A" terminal A9 (Brown/Black wire) and terminal A22 (Brown/Black wire), individually. If less than one volt exists, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If one volt or more exists, repair open in suspect wire(s) between PCM connector terminal A9 or terminal A22 and ground connection G101, located at thermostat housing. See «WIRING DIAGRAMS»(ref-16355) article.

Scheme 25

1. Turn ignition on. Check MAP sensor using OBD-II scan tool. If about zero in. Hg is indicated, go to next step. If about zero in. Hg is not indicated, problem is intermittent. Check for poor connections or loose wires at MAP sensor connector and PCM 16-pin connector "D". See «WIRING DIAGRAMS»(ref-16355) article.
2. Turn ignition off and disconnect MAP sensor 3-pin connector. Turn ignition on. Check MAP sensor using OBD-II scan tool. If about zero in. Hg is indicated, go to next step. If about zero in. Hg is not indicated, replace MAP sensor.
3. Measure voltage between MAP sensor harness connector terminals No. 1 (Yellow/Red wire) and No. 2 (Green/White wire). (Scheme 25) On D16Y5 engine with CVT, if about 5.0 volts exists, go to next step. On D16Y7 and D16Y8 engines, if about 5.0 volts exists, go to step 5). On all models, if about 5.0 volts does not exist, repair open in Yellow/Red wire between PCM 16-pin connector "D" terminal D4 and MAP sensor connector terminal No. 1. See «WIRING DIAGRAMS»(ref-16355) article.
4. On D16Y5 with CVT, turn ignition off. Disconnect 22-pin Transmission Control Module (TCM) connector. TCM is located behind driver side kick panel. Turn ignition on. Check MAP sensor using OBD-II scan tool. If about zero in. Hg is indicated, go to next step. If about zero in. Hg is not indicated, replace TCM.
5. On all models, turn ignition off. Disconnect PCM 16-pin connector "D". Check for continuity between ground and MAP sensor harness connector terminal No. 3 (Red/Green wire). (Scheme 25) If continuity exists, repair short in Red/Green wire between PCM connector and MAP sensor connector. See «WIRING DIAGRAMS»(ref-16355) article. If continuity does not exist, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.

Random Misfire Occurs During Low RPM & Low Engine Load

Check for

1. EGR system malfunction on D16Y5 engine. See DTC P0401, DTC P1491 and DTC P1498 testing.
2. Correct fuel pressure. See FUEL SYSTEM in «BASIC TESTING»(ref-16344) article.
3. A Crankshaft Position (CKP) sensor malfunction. See «DTC P0335, P0336, P1361, P1362, P1381 & P1382 - CKP/TDC/CYP SENSOR»(ref-16347-S40267605002000122900000) testing.
4. Valves incorrectly adjusted.

Random Misfire Occurs During Acceleration

Check for

1. Worn or broken spark plug wires.
2. Worn or damaged distributor ignition housing.
3. Correct fuel pressure. See FUEL SYSTEM in «BASIC TESTING»(ref-16344) article.
4. Malfunctioning Ignition Control Module (ICM). See «BASIC TESTING»(ref-16344) article.

Random Misfire Occurs During High Engine RPM & Load, Or Under Other Random Conditions

Check for

1. Correct fuel pressure. See FUEL SYSTEM in «BASIC TESTING»(ref-16344) article.
2. Worn or broken spark plug wires.
3. Worn or damaged distributor ignition housing.
4. Malfunctioning Ignition Control Module (ICM). See «BASIC TESTING»(ref-16344) article.
5. A Crankshaft Position (CKP) sensor malfunction. See «DTC P0335, P0336, P1361, P1362, P1381 & P1382 - CKP/TDC/CYP SENSOR»(ref-16347-S40267605002000122900000) testing.

Valves incorrectly adjusted. If no problems are found check for

1. Insufficient fuel pressure or inadequate fuel flow.
2. Clogging, blocked or leaking fuel line.
3. Clogged fuel filter.
4. Stuck open fuel pressure regulator.
5. EGR system malfunction (D16Y5 engine).
6. Distributor malfunction.
7. An open or leaking ignition coil wire.
8. Ignition Control Module (ICM) malfunction.
9. Carbon deposits on valves.
10. Low engine compression.
11. Fuel octane level less than specification.
12. A VTEC system malfunction (D16Y5 or D16Y8 engine).
13. A Heated Oxygen Sensor (HO2S) or HO2S circuit malfunction. Repair as necessary.