Home/Honda/Passport/Honda Passport I (1993-1997)/Repair manual/Testing & Diagnostics/Engine Controls - Tests W/codes - 2.6L: Other
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Engine Controls - Tests W/codes - 2.6L: Other Honda Passport I

Testing & Diagnostics 38 illustrations ~1682 words

Hard Failures

Hard failures cause Malfunction Indicator Light (MIL) to glow and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. See CODE IDENTIFICATION table under TROUBLE CODE DEFINITION. If a sensor fails, Electronic Control Module (ECM) will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, vehicle runs but driveability will not be optimum.

Intermittent Failures

Intermittent failures may cause MIL to flicker or glow and go out after intermittent fault goes away. However, corresponding trouble code will be retained in ECM memory. If related fault does not reoccur within a certain time frame, related trouble code will be erased from ECM memory. Intermittent failures may be caused by a sensor, connector or wiring related problems. See INTERMITTENTS in the TESTS W/O CODES - 2.6L article.

RETRIEVING CODES

Note. Codes can also be retrieved using a scan tester. Trouble codes are also referred to as DTCs.

  1. Code retrieval starts with diagnostic circuit check. See «DIAGNOSTIC CIRCUIT CHECK»(ref-15942-S42922698022001122700000) chart under CODE CHARTS. MIL will come on when ignition is on and engine is not running. When engine is started, MIL should go off. If light remains on while engine is running, a trouble code is present.
  2. If light does not come on with ignition on and engine off, inspect MIL circuit before continuing. If MIL fails to operate, see «DIAGNOSTIC CIRCUIT CHECK»(ref-15942-S42922698022001122700000) chart.
  3. To retrieve codes, install jumper wire between ALDL diagnostic leads. (Scheme 8) Turn ignition on. Count number of flashes from MIL to identify code. (Scheme 9) For example, Code 12 will be flashed as follows: flash, pause, flash, flash.
  4. If system is operating properly, Code 12 should be displayed with ignition on and engine off, indicating diagnostic system is capable of storing codes. Code 12 will flash 3 times, followed by any stored trouble codes. Each code will be flashed 3 times starting with lowest code. Once all codes are displayed, cycle will repeat. After codes are retrieved, remove jumper wire from diagnostic leads to exit diagnostic mode.

Scheme 8

Scheme 8

Scheme 9

Scheme 9

CLEARING CODES

  1. After repairs are performed, clear ECM memory of all stored codes. Ensure ignition is off. To clear codes, remove fuse No. 3 from instrument panel fuse block, or remove 60-amp MAIN fuse located in engine compartment fuse block.
  2. Trouble codes can also be cleared by disconnecting negative battery cable. However, other memory functions (clock, radio, etc.) will need to be reset.

CODE CHARTS

Note. To identify ECM connector terminals, see ECM TERMINAL IDENTIFICATION chart. To test ECM power supply, go to TEST NO . 1 chart.

Pin No.Wire ColorMain Connection
1RedPower
2Black/GreenInjector Ground
3Black/YellowDLC (ALDL)
4Blue/YellowIdle Input (WOT Switch)
5Green/BlackAC Input
6Not Used
7GreenCKP Sensor Signal
8Green/WhitePressure Regulator Control
9Not Used10
Light GreenEGR Duty Solenoid11
Not Used12White/Black
Injector No. 213White
Injector No. 114Red
Power15
Not Used16
Not Used17
Trans Input18Green/Black
Monitor19Green/Yellow
Monitor20White
CKP Sensor Reference21White/Green
EGR VSV22Green
MIL23Light Green/White
EVAP VSV24White/Blue
Injector No. 425White/Red
Injector No. 326Black/Green
Injector Ground

ECM 26-PIN TERMINAL IDENTIFICATION

Pin No.Wire ColorMain Connection
1BluePower Signal
2Black/RedGround (Power, Ignition)
3Green/OrangeMAP Sensor Reference
4Red/WhitePower (Backup)
5WhiteVehicle Speed Sensor
6ShieldOxygen Sensor
7Black/WhiteECT Sensor Ground
8Brown/WhiteECT Sensor Input
9Blue/WhiteMAP Sensor Input
10Not Used
11BlackGround (Power)
12Not Used
13Black/RedGround (Power, Ignition)
14RedAirflow Sensor (Power)
15Green/RedWOT Input (WOT Switch)
16Yellow/BlackStarter Switch
17ShieldAirflow Sensor
18Blue/RedMAP Sensor Ground
19BlackAirflow Sensor Ground
20GreenOxygen Sensor Input
21WhiteAirflow Sensor Input
22BlackGround (Power)

ECM 22-PIN TERMINAL IDENTIFICATION

Scheme 10

Scheme 10
CAUTIONPerform all voltage measurements with ECM harness connector installed. Use a high-impedance voltmeter (10,000 ohm minimum). Verify battery voltage is greater than 11 volts.

Scheme 11

Scheme 11: DIAGNOSTIC CIRCUIT CHECK

Circuit Confirmation

  1. Disconnect ECM harness connectors.
  2. Turn ignition switch to ON position.
  3. Ensure battery voltage is present at terminals No. 1, 14 and 4.
  4. Ensure continuity exists between terminals No. 11 and 22.

CODE 12 - SYSTEM NORMAL

This DTC No. 12 is always displayed with the key "ON" and the engine not running and it only means that the engine is not running. This DTC No. 12 is not stored in memory.

Note. If the signal DTC No. 12 only is displayed when the function key is operated after clearing the memory. It indicates that the ECM electrical circuits and self diagnosis system are functioning normally.

Scheme 12

Scheme 12: CODE 12 - SYSTEM NORMAL

CODE 13 - HEATED OXYGEN SENSOR CIRCUIT

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test numbers refer to numbers on diagnostic chart.

  1. This step checks AIR system operation: Idle engine at normal operating temperature. Stop engine. Disconnect AIR hose at check valve and plug check valve. Restart engine and idle, immediately check direction of airflow.
  2. This step tests continuity of oxygen sensor circuit (Green wire) between ECM 22-pin connector terminal No. 20 and oxygen sensor.

Scheme 13

Scheme 13

CODE 14 - SHORTED ENGINE COOLANT TEMPERATURE SENSOR

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 14

Scheme 14: CODE 14 - SHORTED ENGINE COOLANT TEMPERATURE SENSOR

Scheme 15

Scheme 15

CODE 15 - OPEN ENGINE COOLANT TEMPERATURE SENSOR

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 16

Scheme 16

CODE 21 - THROTTLE VALVE SWITCH (IDLE & FULL THROTTLE)

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 17

Scheme 17: CODE 21 - THROTTLE VALVE SWITCH (IDLE & FULL THROTTLE)

Scheme 18

Scheme 18

Scheme 19

Scheme 19

CODE 22 - STARTER SIGNAL

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 20

Scheme 20: CODE 22 - STARTER SIGNAL

CODE 23, 35, 54 POWER TRANSISTOR CIRCUIT

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test numbers refer to numbers on diagnostic chart.

  1. This step checks continuity of power transistor power circuit. Check continuity of ground at ECM terminal No. 13.
  2. Inspecting power transistor: Disconnect coil wire at distributor. Attach Spark Tester (J-125) or equivalent to free end of coil wire. Remove power transistor from bottom of intake manifold, and disconnect harness connector. Connect a 2-wire jumper lead between power transistor connector and power transistor. In one wire of jumper lead install a 1.5-volt dry cell battery with negative side of battery facing power transistor. Ground power transistor to frame and turn ignition on. Disconnect and reconnect jumper lead at power transistor connector. Verify spark exists at spark tester. If spark is not present, replace power transistor.

Scheme 21

Scheme 21

CODE 25, 53 - FUEL PRESSURE REGULATOR VSV

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test number refers to number on diagnostic chart.

  1. Test resistance between Red wire and Green/White wire at VSV connector.

Scheme 22

Scheme 22

Scheme 23

Scheme 23

CODE 26, 27 - CANISTER PURGE VSV

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test number refers to number on diagnostic chart.

  1. Test resistance between Light Green/Red wire and Black/White wire at VSV connector.

Scheme 24

Scheme 24

Scheme 25

Scheme 25

CODE 32 - EGR SYSTEM MALFUNCTION

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test numbers refer to numbers on diagnostic chart.

  1. Specified reappearance pattern: Run engine at idle and normal operating temperature. Keep vehicle at idle for more than 10 seconds at stop. Drive vehicle at 10 MPH. Accelerate to more than 30 MPH. After 10-30 seconds, decelerate to complete stop. Repeat pattern several times.
  2. This step checks EGR operation by re-applying signal vacuum.

Scheme 26

Scheme 26

Scheme 27

Scheme 27

Scheme 28

Scheme 28

Scheme 29

Scheme 29

CODE 33 - FUEL INJECTOR CIRCUIT (OPEN OR GROUNDED)

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 30

Scheme 30: CODE 33 - FUEL INJECTOR CIRCUIT (OPEN OR GROUNDED)

CODE 34 - MAP SENSOR

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 31

Scheme 31: CODE 34 - MAP SENSOR

Scheme 32

Scheme 32

CODE 41 - CRANKSHAFT POSITION SENSOR SIGNAL

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test number refers to number on diagnostic chart.

  1. Inspecting Crankshaft Position (CKP) sensor circuit: Disconnect CKP sensor and ECM connectors. Turn ignition on. Measure CKP sensor voltage and resistance values. See CKP SENSOR SPECIFICATIONS table. If values are not within specification, repair or replace appropriate harness or connector. Reconnect CKP and ECM connectors.
Between Terminals (1)ResistanceVoltage
20 & White0
7 & Green0
Green/Black & Ground10-14
Black & Ground0
(1) Circuit numbers refer to ECM terminal numbers, and wire colors refer to CKP sensor wire colors at connector.
(1)Circuit numbers refer to ECM terminal numbers, and wire colors refer to CKP sensor wire colors at connector.

CKP SENSOR SPECIFICATIONS

Scheme 33

Scheme 33

CODE 43, 65 - THROTTLE VALVE SWITCH

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 34

Scheme 34

CODE 44, 45 - OXYGEN SENSOR-LEAN/RICH FUEL MIXTURE

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test numbers refer to numbers on diagnostic chart.

  1. Measure voltage at oxygen sensor connector.
  2. Jumper wire allows voltage measurement of circuit.

Scheme 35

Scheme 35

Scheme 36

Scheme 36

CODE 51, 52 - FAULTY ECM RAM/ROM

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Note. Test number refers to number on diagnostic chart.

  1. Before replacing ECM, check circuit connections: Disconnect ECM harness connectors. Inspect all terminals and repair as necessary. Reconnect ECM harness connectors, and road test vehicle. Check for codes. If condition persists or code reappears, replace ECM.

Scheme 37

Scheme 37

CODE 61, 62 - AIRFLOW SENSOR SIGNAL

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 38

Scheme 38: CODE 61, 62 - AIRFLOW SENSOR SIGNAL

Scheme 39

Scheme 39

CODE 63 - VEHICLE SPEED SENSOR SIGNAL

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Code 63 can be set, without a system failure, under following conditions

  1. Auto. Trans. In Drive position, with brake pedal depressed and accelerator pedal depressed more than halfway for more than 3 seconds.
  2. Manual Trans. Under severe climbing conditions, with vehicle stationary, accelerator pedal depressed more than halfway for more than 3 seconds, and clutch partially engaged.

Note. Test numbers refer to numbers on diagnostic chart.

  1. Check for continuity between ECM 22-pin connector terminal No. 5 (White wire) and ground. Disconnect speedometer cable at transmission. Tester should pulsate between open and continuity as speedometer cable is rotated slowly. NOTE: Instrument cluster has two 12-pin connectors. Ensure appropriate wire color is tested.
  2. Ensure continuity exists on White wire between ECM 22-pin connector terminal No. 5 and instrument cluster 12-pin connector terminal No. 9. Ensure continuity exists on Black/White wire between instrument cluster 12-pin connector terminal No. 9 and ground.
  3. Remove instrument cluster assembly. Check continuity between terminals No. 1 and 2. Tester should pulsate between open and continuity as speedometer inner shaft is rotated slowly.

Scheme 40

Scheme 40

Scheme 41

Scheme 41

CODE 64 - FUEL INJECTOR CIRCUIT (ECM TRANSISTOR)

Note. See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

Scheme 42

Scheme 42

SUMMARY

If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to TESTS W/O CODES - 2.6L article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

Wiring Diagram (Passport 2.6L - 1 Of 3). Scheme 43

Scheme 43: Wiring Diagram (Passport 2.6L - 1 Of 3)

Wiring Diagram (Passport 2.6L - 2 Of 3). Scheme 44

Scheme 44: Wiring Diagram (Passport 2.6L - 2 Of 3)

Wiring Diagram (Passport 2.6L - 3 Of 3). Scheme 45

Scheme 45: Wiring Diagram (Passport 2.6L - 3 Of 3)