[13A] MULTIPORT FUEL INJECTION (MPI) <4G63> - - TROUBLESHOOTING - CHECK AT THE ECU TERMINALS | PRINT PAGE / INDEX / PRIOR / NEXT

| CHECK AT THE ECU TERMINALS
| TERMINAL VOLTAGE CHECK CHART
| Connect a needle-nosed wire probe to a voltmeter probe. Insert the needle-nosed wire probe into each of the engine-A/T-ECU connector terminals from the wire side, and measure the voltage while referring to the check chart. NOTE: Make the voltage measurement with the engine-A/T-ECU connector connected. You may find it convenient to pull out the engine-A/T-ECU to make it easier to reach the connector terminals. The checks can be carried out off the order given in the chart. CAUTION Short-circuiting the positive (+) probe between a connector terminal and earth could damage the vehicle wiring, the sensor, engine-A/T-ECU or all of them. Be careful to prevent this! If voltmeter shows any division from standard value, check the corresponding sensor, actuator and related electrical wiring, then repair or replace. After repair or replacement, recheck with the voltmeter to confirm that the repair has corrected the problem.
Engine-A/T-ECU Connector Terminal Arrangement
Terminal No. | Check item | Check condition (Engine condition) | Normal condition
--- | --- | --- | ---
1 | No. 1 injector | While engine is idling after having warmed up, suddenly depress the accelerator pedal. | From 11 - 14 V, momentarily drops slightly
9 | No. 2 injector
24 | No. 3 injector
2 | No. 4 injector
3 | Oxygen sensor heater (front) <SOHC> | Engine: Idling after warming up | 1 V or less
Engine r/min:Racing | System voltage
3 | Oxygen sensor heater<DOHC> | Engine: Idling after warming up | 1 V or less
Engine r/min:Racing | System voltage
6 | EGR control solenoid Valve | Ignition switch: "ON" | System Voltage
While engine is idling, suddenly depress the accelerator pedal. | From system voltage, momentarily drops
8 | Alternator G terminal | Engine: Warm, idle (radiator fan: OFF) Headlamp: OFF → ON Stop lamp: OFF → ON Rear defogger switch: OFF → ON | Voltage increases by 0.2 - 3.5 V
11 | Ignition coil - No. 1, No. 4 | Engine r/min: 3,000 r/min | 0.3 - 3.0 V
12 | Ignition coil - No. 2, No. 3
14 | Stepper motor coil <A1> | Engine: Soon after the warmed up engine is star A/C switch: OFF → ON (A/C compressor is operating) | System voltage ⇔ 1 V or less (Changes repeatedly)
28 | Stepper motor coil <A2>
15 | Stepper motor coil <B1>
29 | Stepper motor coil <B2>
18 | Fan controller | Radiator and condenser fan is not operating | 0 - 0.3 V
Radiator and condenser fan is operating | 0.7 V or more
19 | Air flow sensor reset Signal | Engine: Idle speed | 0 - 1 V
Engine r/min: 3,000 r/min | 6 - 9 V
20 | Fuel pump relay | Ignition switch: ON | System voltage
Engine: Idle speed | 1 V or less
21 | A/C relay | Engine: Idle speed A/C switch: OFF → ON (A/C compressor is operating) | System voltage or Momentarily 6V or more → 1 V or less
22 | Engine warming lamp | Ignition switch: "LOCK" (OFF) → "ON" | 1 V or less → System voltage (After several seconds have elapsed)
26 | Oxygen sensor heater (reart) <SOHC> | Engine: Idling after warming up | 1 V or less
Engine r/min:Racing | System voltage
34 | Purge control solenoid valve | Ignition switch: "ON" | System voltage
Running at 3,500 r/min while engine is warming up after having been started. | 1 V or less
41 | Power supply | Ignition switch: "ON" | System voltage
47
43 | Tachometer signal | Engine r/min: 3,000 r/min | 2.5 - 5.5 V
44 | Engine coolant temperature sensor | Ignition switch: "ON" | When engine coolant temperature is -20°C | 3.9 - 4.5 V
When engine coolant temperature is 0°C | 3.2 - 3.8 V
When engine coolant temperature is 20°C | 2.3 - 2.9 V
When engine coolant temperature is 40°C | 1.3 - 1.9 V
When engine coolant temperature is 60°C | 0.7 - 1.3 V
When engine coolant temperature is 80°C | 0.3 - 0.9 V
45 | Crank angle sensor | Engine: Cranking | 0.4 - 4.0 V
Engine: Idling speed | 1.5 - 2.5 V
46 | Sensor impressed voltage | Ignition switch: "ON" | 4.9 - 5.1 V
49 | Control relay (Power supply) | Ignition switch: "LOCK" (OFF) | System voltage
Ignition switch: "ON" | 1 V or less
52 | Power steering fluid pressure switch | Engine: Idling after warming up | When steering wheel is Stationary | System voltage
When steering wheel is turned | 1 V or less
54 | Alternator FR terminal | Engine: Warm, idle (radiator fan: OFF) Headlamp: OFF → ON Stop lamp: OFF → ON Rear defogger switch: OFF → ON | Voltage decreases
55 | Barometric pressure sensor<DOHC> | Ignition switch: "ON" | Altitude: 0 m | 3.8 - 4.2 V
Altitude: 600 m | 3.5 - 3.9 V
Altitude: 1,200 m | 3.3 - 3.7 V
Altitude: 1,800 m | 3.0 - 3.4 V
56 | Camshaft position sensor | Engine: Cranking | 0.4 - 3.0 V
Engine: Idling | 2.0 - 3.0 V
58 | Ignition switch - ST | Engine: Cranking | 8 V or more
61 | A/C load signal | Refer to GROUP 55 - Troubleshooting (Inspection at the Automatic compressor - ECU Terminal)
62 | A/C pressure sensor | Engine: Idling A/C switch: ON | When A/C is "MAX, COOL" condition (when the load by A/C is high) | 2.2 V or more
When A/C is "MAX, HOT" condition (when the load by A/C is low) | 1.8 V or less
64 | Intake air temperature sensor | Ignition switch: "ON" | When intake air temperature is -20°C | 3.8 - 4.4 V
When intake air temperature is 0°C | 3.2 - 3.8 V
When intake air temperature is 20°C | 2.3 - 2.9 V
When intake air temperature is 40°C | 1.5 - 2.1 V
When intake air temperature is 60°C | 0.8 - 1.4 V
When intake air temperature is 80°C | 0.4 - 1.0 V
65 | Air flow sensor | Engine: Idle speed | 2.2 - 3.2 V
Engine r/min: 2,500 r/min
66 | Backup power supply | Ignition switch: "LOCK" (OFF) | System voltage
71 | Oxygen sensor (front) <SOHC> | Engine: Running at 2,500 r/min after warmed up (Check using a digital type voltmeter) | 0 ⇔ 0.8 V (Changes repeatedly)
71 | Oxygen sensor <DOHC> | Engine: Running at 2,500 r/min after warmed up (Check using a digital type voltmeter) | 0 ⇔ 0.8 V (Changes repeatedly)
73 | Oxygen sensor (rear) <SOHC> | Engine: Idling after warmed up (Check using a digital type voltmeter) | 0 ⇔ 0.6 V (Changes repeatedly)
78 | Throttle position sensor | Ignition switch: "ON" | Set throttle valve to idle Position | 0.335 - 0.935 V
Fully open throttle valve | 4.4 - 5.3 V
83 | A/C switch | Engine: Idle speed | Turn the A/C switch OFF | 0.5 V or less
Turn the A/C switch ON (A/C compressor is operating) | System voltage
86 | Waste gate solenoid valve | Ignition switch: "ON" | System voltage
Engine: Idling after warmed up | 0.8 - 2.4 V
91 | Manifold absolute pressure sensor<SOHC> | Ignition switch: "ON" | Altitude: 0 m | 3.8 - 4.2 V
Altitude: 600 m | 3.5 - 3.9 V
Altitude: 1,200 m | 3.3 - 3.7 V
Altitude: 1,800 m | 3.0 - 3.4 V
Engine: Idling after warmed ul | 0.9 - 1.9V
Engine:While engine is idling, suddenly depress the accelerator pedal | From 0.9 - 1.9V, momentarily drops
91 | Manifold differential pressure sensorr<DOHC> | Ignition switch: "ON" | 0.8 - 2.4 V
Engine:While engine is idling, suddenly depress the accelerator pedal | From 0.8 - 2.4 V, momentarily drops
93 | Fuel pressure control solenoid valve | Ignition switch: "ON" | System voltage
Engine:Cranking → Idling | 1 V or less→ System voltages
98 | Ignition switch - IG | Ignition switch: "ON" | System voltage
| CHECK CHART FOR RESISTANCE AND CONTINUITY BETWEEN TERMINALS Turn the ignition switch to "LOCK" (OFF) position. Disconnect the engine-A/T-ECU connector. Measure the resistance and check for continuity between the terminals of the engine-A/T-ECU harness-side connector while referring to the check chart. NOTE: When measuring resistance and checking continuity, a harness for checking contact pin pressure should be used instead of inserting a test probe. Checking need not be carried out in the order given in the chart. CAUTION If the terminals that should be checked are mistaken, or if connector terminals are not correctly shorted to earth, damage may be caused to the vehicle wiring, sensors, engine-A/T-ECU and/or ohmmeter. Be careful to prevent this! If the ohmmeter shows any deviation from the standard value, check the corresponding sensor, actuator and related electrical wiring, and the repair or replace. After repair or replacement, recheck with the ohmmeter to confirm that the repair or replacement has corrected the problem.
Engine-A/T-ECU Harness Side Connector Terminal Arrangement
Terminal No. | Inspection item | Normal condition (Check condition)
--- | --- | ---
1 - 41 | No. 1 injector | 13 - 16 Ω (At 20°C)
9 - 41 | No. 2 injector
24 - 41 | No. 3 injector
2 - 41 | No. 4 injector
3 - 41 | Oxygen sensor heater(front) <SOHC> | 4.5 - 8.0 Ω (At 20°C)
3 - 41 | Oxygen sensor heater <DOHC> | 11 - 18 Ω (At 20°C)
26 - 41 | Oxygen sensor heater(rear <SOHC> | 11 - 18 Ω (At 20°C)
6 - 41 | EGR control solenoid valve | 29 - 35 Ω (At 20°C)
14 - 41 | Stepper motor coil (A1) | 28 - 33 Ω (At 20°C)
28 - 41 | Stepper motor coil (A2)
15 - 41 | Stepper motor coil (B1)
29 - 41 | Stepper motor coil (B2)
34 - 41 | Purge control solenoid valve | 30 - 34 Ω (At 20°C)
42 - Body earth | ECU earth | Continuity (0 Ω)
48 - Body earth
44 - 81 | Engine coolant temperature sensor | 14 - 17 kΩ (When coolant temperature is -20°C)
5.1 - 6.5 kΩ (When coolant temperature is 0°C)
2.1 - 2.7 kΩ (When coolant temperature is 20°C)
0.9 - 1.3 kΩ (When coolant temperature is 40°C)
0.48 - 0.68 kΩ (When coolant temperature is 60°C)
0.26 - 0.36 kΩ (When coolant temperature is 80°C)
64 - 81 | Intake air temperature sensor | 13 - 17 kΩ (When intake air temperature is -20°C)
5.3 - 6.7 kΩ (When intake air temperature is 0°C)
2.3 - 3.0 kΩ (When intake air temperature is 20°C)
1.0 - 1.5 kΩ (When intake air temperature is 40°C)
0.56 - 0.76 kΩ (When intake air temperature is 60°C)
0.30 - 0.42 kΩ (When intake air temperature is 80°C)

[13A] MULTIPORT FUEL INJECTION (MPI) <4G63> - - TROUBLESHOOTING - CHECK AT THE ECU TERMINALS | PRINT PAGE / INDEX / PRIOR / NEXT

©2004 Mitsubishi Motors Corporation