Engine Controls - Tests W/codes: Diagnosis — Honda Prelude IV (1992-1996)

DIAGNOSTIC TROUBLE CODE DEFINITION

Code (1)	System Affected	Probable Cause
0	ECM	No Signal To ECM
1	Heated Oxygen Sensor (HO2S)	Problem In HO2S Circuit
3	MAP Sensor	Electrical Problem In MAP Sensor
4	Crank Angle Sensor (CKP)	Open Or Shorted Signal Circuit
5	MAP Sensor	Electrical problem in MAP Sensor
6	Engine Coolant Temperature (ECT) Sensor	Open Or Shorted Signal Circuit
7	Throttle Position (TP) Sensor	Open Or Shorted Signal Circuit
8	Crank Angle Sensor (TDC)	Open Or Shorted Signal Circuit
9	Crank Angle Sensor (CYP)	Open Or Shorted Signal Circuit
10	Intake Air Temperature(IAT)	Problem With Sensor
12	EGR System	No EGR Action
13	Barometric Pressure (BARO) Sensor	Problem With PA Circuit
14	Idle Air Control(IAC) Valve	Open Or Shorted Signal Circuit
15	Ignition Output Signal	Electrical Problem In Signal Circuit
16	Fuel Injector	Problem In Fuel Injector Circuit
17	Vehicle Speed Sensor (VSS)	Open Or Shorted Signal Circuit
20 (2)	Electrical Load Detector (ELD)	Problem With ELD Circuit
21	Spool Solenoid Valve	Problem With VTEC Spool Solenoid Circuit
22 22	VTEC Oil Pressure Switch	Problem In VTEC Oil Pressure Switch Circuit
23	Knock Sensor (KS)	Knock Sensor Circuit Fault
30	A/T FI Signal A	Problem In A/T Control Unit And ECM Circuit
31	A/T FI Signal B	Problem In A/T Control Unit And ECM Circuit
41	Heated Oxygen Sensor (HO2S) Heater	Problem With HO2S Circuit
43	Fuel Supply System	Problem With HO2S Circuit Or Fuel System
(1) If codes other than these are indicated, repeat self-diagnosis. If code(s) reappear, substitute a known good ECM, and recheck codes. If code(s) clear, replace ECM. (2) MIL does not come on when there is a malfunction in ELD circuit, but code is stored in ECM memory.

(1)

(2)

DIAGNOSTIC TROUBLE CODE IDENTIFICATION

TEST EQUIPMENT

All voltage tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated differently in testing procedure.

On Accord and Prelude, when directed by testing to install Engine Control Module (ECM) test harness, turn ignition off. Connect ECM Test Harness (07LAJ-PT3010A) between ECM and ECM connector. (Scheme 1) Follow testing directions. For test harness terminal identification (Scheme 4) For oil pressure gauge hookup (Scheme 3)

Scheme 1

Scheme 1: TEST EQUIPMENT

On Odyssey, use Backprobe Set (07SAZ-001000A) to backprobe Engine Control Module (ECM) when directed by testing. (Scheme 2) For ECM connector terminal identification (Scheme 4)

Scheme 2

Scheme 3

DIAGNOSTIC TROUBLE CODE CHARTS

Note. In the following diagnostic trouble code charts, illustrations and schematics are courtesy of American Honda Motor Co., Inc.

Using Diagnostic Trouble Code Charts

To use DIAGNOSTIC TROUBLE CODE CHARTS, see RETRIEVING CODES under SELF-DIAGNOSTIC SYSTEM. After codes have been recorded, proceed to appropriate DIAGNOSTIC TROUBLE CODE CHART.

When directed by chart to install ECM test harness, turn ignition off. Connect ECM Test Harness (07LAJ-PT3010A ) between ECM and connector. (Scheme 4) Follow code chart directions.

Scheme 4

Scheme 4: Using Diagnostic Trouble Code Charts

Note. The Following Flow Charts are Courtesy of American Honda Motors Co., Inc.

Flow Chart (1 Of 5) Code/No Code - No Start Trouble Shooting. Scheme 5

Scheme 5: Flow Chart (1 Of 5) Code/No Code - No Start Trouble Shooting

Flow Chart (2 Of 5) Code/No Code - No Start Trouble Shooting. Scheme 6

Scheme 6: Flow Chart (2 Of 5) Code/No Code - No Start Trouble Shooting

Flow Chart (3 Of 5) Code/No Code - No Start Trouble Shooting. Scheme 7

Scheme 7: Flow Chart (3 Of 5) Code/No Code - No Start Trouble Shooting

Flow Chart (4 Of 5) Code/No Code - No Start Trouble Shooting. Scheme 8

Scheme 8: Flow Chart (4 Of 5) Code/No Code - No Start Trouble Shooting

Flow Chart (5 Of 5) Code/No Code - No Start Trouble Shooting. Scheme 9

Scheme 9: Flow Chart (5 Of 5) Code/No Code - No Start Trouble Shooting

Code 1 Flow Chart Heated Oxygen Sensor (HO2S). Scheme 10

Scheme 10: Code 1 Flow Chart Heated Oxygen Sensor (HO2S)

Code 3 Flow Chart (1 Of 3) MAP Sensor Circuit. Scheme 11

Scheme 11: Code 3 Flow Chart (1 Of 3) MAP Sensor Circuit

Code 3 Flow Chart (2 Of 3) MAP Sensor Circuit. Scheme 12

Scheme 12: Code 3 Flow Chart (2 Of 3) MAP Sensor Circuit

Code 3 Flow Chart (3 Of 3) MAP Sensor Circuit. Scheme 13

Scheme 13: Code 3 Flow Chart (3 Of 3) MAP Sensor Circuit

Code 4, 8 AND/OR 9 Flow Chart (1 Of 2) TDC/CKP/CYP Sensor. Scheme 14

Scheme 14: Code 4, 8 AND/OR 9 Flow Chart (1 Of 2) TDC/CKP/CYP Sensor

Code 4, 8 AND/OR 9 Flow Chart (2 Of 2) TDC/CKP/CYP Sensor. Scheme 15

Scheme 15: Code 4, 8 AND/OR 9 Flow Chart (2 Of 2) TDC/CKP/CYP Sensor

Code 5 Flow Chart (1 Of 2) MAP Sensor Circuit. Scheme 16

Scheme 16: Code 5 Flow Chart (1 Of 2) MAP Sensor Circuit

Code 5 Flow Chart (2 Of 2) MAP Sensor Circuit. Scheme 17

Scheme 17: Code 5 Flow Chart (2 Of 2) MAP Sensor Circuit

Code 6 Flow Chart (1 Of 2) Engine Coolant Temperature (ECT) Sensor. Scheme 18

Scheme 18: Code 6 Flow Chart (1 Of 2) Engine Coolant Temperature (ECT) Sensor

Code 6 Flow Chart (2 Of 2) Engine Coolant Temperature (ECT) Sensor. Scheme 19

Scheme 19: Code 6 Flow Chart (2 Of 2) Engine Coolant Temperature (ECT) Sensor

Code 7 Flow Chart (1 Of 2) Throttle Position (TP) Sensor. Scheme 20

Scheme 20: Code 7 Flow Chart (1 Of 2) Throttle Position (TP) Sensor

Code 7 Flow Chart (2 Of 2) Throttle Position (TP) Sensor. Scheme 21

Scheme 21: Code 7 Flow Chart (2 Of 2) Throttle Position (TP) Sensor

Code 10 Flow Chart (1 Of 2) Intake Air Temperature (IAT) Sensor. Scheme 22

Scheme 22: Code 10 Flow Chart (1 Of 2) Intake Air Temperature (IAT) Sensor

Code 10 Flow Chart (2 Of 2) Intake Air Temperature (IAT) Sensor. Scheme 23

Scheme 23: Code 10 Flow Chart (2 Of 2) Intake Air Temperature (IAT) Sensor

Code 12 Flow Chart (1 Of 5) EGR System. Scheme 24

Scheme 24: Code 12 Flow Chart (1 Of 5) EGR System

Code 12 Flow Chart (2 Of 5) EGR System. Scheme 25

Scheme 25: Code 12 Flow Chart (2 Of 5) EGR System

Code 12 Flow Chart (3 Of 5) EGR System. Scheme 26

Scheme 26: Code 12 Flow Chart (3 Of 5) EGR System

Code 12 Flow Chart (4 Of 5) EGR System. Scheme 27

Scheme 27: Code 12 Flow Chart (4 Of 5) EGR System

Code 12 Flow Chart (5 Of 5) EGR System. Scheme 28

Scheme 28: Code 12 Flow Chart (5 Of 5) EGR System

Code 13 Flow Chart Barometric Pressure (BARO) Sensor. Scheme 29

Scheme 29: Code 13 Flow Chart Barometric Pressure (BARO) Sensor

Code 14 Flow Chart (1 Of 2) Idle Air Control (IAC) Valve. Scheme 30

Scheme 30: Code 14 Flow Chart (1 Of 2) Idle Air Control (IAC) Valve

Code 14 Flow Chart (2 Of 2) Idle Air Control (IAC) Valve. Scheme 31

Scheme 31: Code 14 Flow Chart (2 Of 2) Idle Air Control (IAC) Valve

Code 15 Flow Chart (1 Of 2) Ignition Output Signal. Scheme 32

Scheme 32: Code 15 Flow Chart (1 Of 2) Ignition Output Signal

Code 15 Flow Chart (2 Of 2) Ignition Output Signal. Scheme 33

Scheme 33: Code 15 Flow Chart (2 Of 2) Ignition Output Signal

Code 16 Flow Chart (1 Of 3) Fuel Injectors. Scheme 34

Scheme 34: Code 16 Flow Chart (1 Of 3) Fuel Injectors

Code 16 Flow Chart (2 Of 3) Fuel Injectors. Scheme 35

Scheme 35: Code 16 Flow Chart (2 Of 3) Fuel Injectors

Code 16 Flow Chart (3 Of 3) Fuel Injectors. Scheme 36

Scheme 36: Code 16 Flow Chart (3 Of 3) Fuel Injectors

Code 17 Flow Chart (1 Of 2) Vehicle Speed Sensor (VSS). Scheme 37

Scheme 37: Code 17 Flow Chart (1 Of 2) Vehicle Speed Sensor (VSS)

Code 17 Flow Chart (2 Of 2) Vehicle Speed Sensor (VSS). Scheme 38

Scheme 38: Code 17 Flow Chart (2 Of 2) Vehicle Speed Sensor (VSS)

Code 20 Flow Chart (1 Of 2) Electrical Load Detector (ELD). Scheme 39

Scheme 39: Code 20 Flow Chart (1 Of 2) Electrical Load Detector (ELD)

Code 20 Flow Chart (2 Of 2) Electrical Load Detector (ELD). Scheme 40

Scheme 40: Code 20 Flow Chart (2 Of 2) Electrical Load Detector (ELD)

Scheme 41

Scheme 41: CODE 21 - VTEC SOLENOID VALVE CIRCUIT

Scheme 42

Scheme 43

Scheme 43: CODE 22 - VTEC PRESSURE SWITCH CIRCUIT

Scheme 44

Scheme 45

Code 23 Flow Chart (1 Of 2) Knock Sensor (KS). Scheme 46

Scheme 46: Code 23 Flow Chart (1 Of 2) Knock Sensor (KS)

Code 23 Flow Chart (2 Of 2) Knock Sensor (KS). Scheme 47

Scheme 47: Code 23 Flow Chart (2 Of 2) Knock Sensor (KS)

Code 30 OR 31 Flow Chart A/T FI Signal "A" (30) OR "B" (31). Scheme 48

Scheme 48: Code 30 OR 31 Flow Chart A/T FI Signal "A" (30) OR "B" (31)

Code 41 Flow Chart (1 Of 3) Heated Oxygen Sensor (HO2S) Heater. Scheme 49

Scheme 49: Code 41 Flow Chart (1 Of 3) Heated Oxygen Sensor (HO2S) Heater

Code 41 Flow Chart (2 Of 3) Heated Oxygen Sensor (HO2S) Heater. Scheme 50

Scheme 50: Code 41 Flow Chart (2 Of 3) Heated Oxygen Sensor (HO2S) Heater

Code 41 Flow Chart (3 Of 3) Heated Oxygen Sensor (HO2S) Heater. Scheme 51

Scheme 51: Code 41 Flow Chart (3 Of 3) Heated Oxygen Sensor (HO2S) Heater

Code 43 Flow Chart (1 Of 2) Fuel Supply System. Scheme 52

Scheme 52: Code 43 Flow Chart (1 Of 2) Fuel Supply System

Code 43 Flow Chart (1 Of 2) Fuel Supply System. Scheme 53

Scheme 53: Code 43 Flow Chart (1 Of 2) Fuel Supply System

Engine Controls - Tests W/codes: Diagnosis Honda Prelude IV