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Generators & Regulators - Evolution Mitsubishi Lancer Evolution VIII

Charging System 22 illustrations ~2347 words

DESCRIPTION

Note. See appropriate SELF DIAGNOSTICS article in ENGINE PERFORMANCE to properly diagnose charging system.

The charging system charges the battery with the generator output to keep the battery charged at a constant level during varying electrical load.

OPERATION

Rotation of the excited field coil generates AC voltage in the stator. This alternating current is rectified through diodes to DC voltage having a waveform. The average output voltage fluctuates slightly with the generator load condition.

When the ignition switch is turned on, current flows in the field coil and initial excitation of the field coil occurs. When the stator coil begins to generate power after the engine is started, the field coil is excited by the output current of the stator coil. The generator output voltage rises as the field current increases and it falls as the field current decreases. When the battery positive voltage (generator S terminal voltage) reaches a regulated voltage of approximately 14.4V, the field current is cut off. When the battery positive voltage drops below the regulated voltage, the voltage regulator regulates the output voltage to a constant level by controlling the field current. In addition, when the field current is constant, the generator output voltage rises as the engine speed increases. (Scheme 42)

Scheme 42

Scheme 42: OPERATION
Scheme 42: OPERATION

BELT TENSION

For belt tension, see ADJUSTMENTS .

TROUBLE SHOOTING

  1. Is battery in good condition? If Yes, then go to next step. If No, then charge or replace battery.
  2. Is generator drive belt in good condition? If Yes, then go to next step. If No, then adjust belt tension or replace belt.
  3. Does the generator malfunction light come on when the ignition switch is turned on? If Yes, then go to next step. If No: Check the ignition switch. Check for burnt-out generator malfunction light. Check the generator. Check the generator malfunction light-related circuits.
  4. Does the generator malfunction light go out after starting the engine? If Yes, then go to next step. If No, check the generator.
  5. Is an oscilloscope available? If Yes, then go to next step. If No, then go to step 7 .
  6. Does the oscilloscope show a normal wave pattern? If Yes, then go to next step. If No, then check the generator.
  7. Turn the engine on and idle at 2500 RPM. Turn the headlights on with the High Beams on. Be sure that there is voltage between generator terminal B and the positive battery terminal of 0.5V or less. Check that the voltage between the negative battery terminal and generator body is 0.5V or less. Are the generator output line and ground line in good condition? If Yes, then go to next step. If No, check the generator output line and ground line.
  8. Is the output current normal? If Yes, then go to next step. If No, then check the generator.
  9. Is the regulated voltage normal? If Yes, then go to next step. If No, then check the generator.
  10. Is the voltage drop in the generator output line normal? If Yes, then generator is normal. Check other systems. If No, then check the output line.

GENERATOR OUTPUT LINE VOLTAGE DROP TEST

Required special tools: MB991958: Scan Tool MUT-III Sub Assembly, MB991824: V.C.I., MB991827: MUT-III USB Cable, MB991911: MUT-III Main Harness B.

This test determines whether the wiring from the generator B-terminal to positive battery terminal (including the fusible link) is in good condition or not. (Scheme 43)

Scheme 43

Scheme 43: GENERATOR OUTPUT LINE VOLTAGE DROP TEST
Scheme 43: GENERATOR OUTPUT LINE VOLTAGE DROP TEST
  1. Always be sure to check following before testing: Generator installation. Generator drive belt tension. Fusible link. Abnormal noise form generator while engine is running.
  2. Tune ignition switch to LOCK (OFF) position.
  3. Disconnect negative battery cable.
  4. Connect a clamp-type DC test ammeter with a range of 0-100A to the generator B terminal output wire.
  5. Connect a digital-type voltmeter between the generator B terminal and the positive battery terminal. (Connect the positive lead of the voltmeter to the B terminal, and then connect the negative lead of the voltmeter to the positive battery cable.)
  6. Reconnect the negative battery cable.
  7. Connect an engine tachometer or scan tool MB991958.
  8. Leave the hood open.
  9. Start the engine.
  10. With the engine running at 2500 RPM, turn the headlights and other lights on and off to adjust the generator load so that the value displayed on the ammeter is slightly above 30A. Read the voltmeter. Voltage reading at or below limit value means voltage drop between generator and batter is OK. There should be a maximum voltage of 0.3V.
  11. If the value displayed on the voltmeter is above the limit value, there is probably a malfunction in the generator output wire. Check the wiring between the generator B terminal and the positive battery terminal (including fusible link). If a terminal is not sufficiently tight or if the harness has become discolored due to overheating, repair and then test again.
  12. After the test, run the engine at idle.
  13. Turn off all lights and turn the ignition switch to the LOCK (OFF) position.
  14. Disconnect the engine tachometer or scan tool MB991958.
  15. Disconnect the negative battery cable.
  16. Disconnect the ammeter and voltmeter.
  17. Connect the negative battery cable.
  18. Run the engine for 10 minutes at an idle.

OUTPUT CURRENT TEST

Required special tool: MB991958: Scan Tool MUT-III Sub Assembly, MB991824: V.C.I., MB991827 MUT-III USB Cable, MB5991911: MUT-III Main Harness B. This test determines whether the generator outputs normal current. For best results, use a charging system tester. If not available, follow the steps below. (Scheme 44)

Scheme 44

Scheme 44: OUTPUT CURRENT TEST
Scheme 44: OUTPUT CURRENT TEST
  1. Before the test, always be sure to check the following. Generator installation. NOTE: The battery to be used should be slightly discharged. The load in a fully-charged battery will be insufficient and the test may not be able to be carried out correctly. Battery. Generator drive belt tension. Fusible link. Abnormal noise from the generator while the engine is running.
  2. Turn the ignition switch to the LOCK (OFF) position.
  3. Disconnect the negative battery cable.
  4. Connect a clamp-type DC test ammeter with a range of 0-100A to the generator B terminal output wire.
  5. Connect a voltmeter with a range of 0-20V between the generator B terminal and ground. (Connect the positive lead of the voltmeter to the B terminal, and then connect the negative lead of the voltmeter to ground.)
  6. Connect the negative battery cable.
  7. Connect an engine tachometer or scan tool MB991958.
  8. Leave the hood open.
  9. Check to be sure that the reading on the voltmeter is equal to the battery positive voltage.
  10. After turning on the headlights, start the engine.
  11. Immediately after setting the headlights to high beam and turning the heater blower switch to the highest position, increase the engine speed to 2,500 RPM and read the maximum current output value displayed on the ammeter. Limit value: 70 percent of nominal current output.
  12. The reading on the ammeter should be above the limit value. If the reading is below the limit value and the generator output wire is normal, remove the generator from the engine and check the generator.
  13. Run the engine at idle speed after the test.
  14. Turn the ignition switch to the LOCK (OFF) position.
  15. Disconnect the engine tachometer or scan tool MB991958.
  16. Disconnect the negative battery cable.
  17. Disconnect the ammeter and voltmeter.
  18. Connect the negative battery cable.
  19. Run the engine for 10 minutes at an idle.

REGULATED VOLTAGE TEST

Required special tools

  1. MB991958: Scan Tool MUT-III Sub Assembly.
  2. MB991824: V.C.I.
  3. MB991827: MUT-III USB Cable.
  4. MB991911: MUT-III Main Harness B.
  5. MB991519: Generator Harness Connector.

This test determines whether the voltage regulator is correctly controlling the generator output voltage. See

Scheme 45

Scheme 45
Scheme 45
  1. Always be sure to check the following before the test: Generator installation. Check to be sure that the battery installed in the vehicle is fully charged. Generator drive belt tension. Fusible link. Abnormal noise from the generator while the engine is running.
  2. Turn the ignition switch to the LOCK (OFF) position.
  3. Disconnect the negative battery cable.
  4. Use the special tool Generator Harness Connector: MB991519) to connect a digital-type voltmeter between the generator S terminal and ground. (Connect the positive lead of the voltmeter to the S terminal, and then connect the negative lead of the voltmeter to a secure ground or to the negative battery terminal.)
  5. Connect a camp-type DC test ammeter with a range of 0-100A to the generator B terminal output wire.
  6. Reconnect the negative battery cable.
  7. Connect an engine tachometer, or scan tool MB991958.
  8. Turn the ignition switch to the ON position and check that the reading on the voltmeter is equal to the battery positive voltage.
  9. Check to be sure that all lights and accessories are off.
  10. Start the engine.
  11. Increase the engine speed to 2,500 RPM
  12. Read the value displayed on the voltmeter when the current output by the generator becomes 10A or less.
  13. If the voltage reading conforms to the value in the voltage regulation table, then the voltage regulator is operating normally. If the voltage is outside the standard value, there is a malfunction of the voltage regulator or the generator. See «REGULATOR VOLTAGE SPECIFICATIONS TABLE»(/mitsubishi/lancer-evolution/viii-2003-2005/remont/charging-system/#generators-regulators-evolution) .
  14. After the test, lower the engine speed to idle.
  15. Turn the ignition switch to the LOCK (OFF) position.
  16. Disconnect the engine tachometer or scan tool MB991958.
  17. Disconnect the negative battery cable.
  18. Disconnect the ammeter and voltmeter.
  19. Connect the negative battery cable.
  20. Run the engine for 10 minutes at an idle.
Ambient Temp. °F (°C)Voltage
Terminal S
4 (-20)14.2-15.4
68 (20)13.9-14.9
140 (60)13.4-14.5
176 (80)13.1-14.2

REGULATOR VOLTAGE SPECIFICATIONS

Abnormal Waveforms

The size of the waveform patterns can differ greatly, depending on the adjustment of the variable knob on the oscilloscope. (Scheme 46)

Identification of abnormal waveforms is easier when there is a large output current (regulator is not operating). Waveforms can be observed when the headlights are illuminated.

Check the conditions of the generator malfunction light (illuminated/not illuminated) also, and carry out a total check.

Scheme 46

Scheme 46: Abnormal Waveforms
Scheme 46: Abnormal Waveforms

Measurement Method

Connect the oscilloscope special patterns pick-up to the generator B terminal. (Scheme 47)

Scheme 47

Scheme 47: Measurement Method
Scheme 47: Measurement Method

Standard Waveform

Note. The voltage waveform of the generator B terminal can undulate. This waveform is produced when the regulator operates according to fluctuations in the generator load (current), and is normal for the generator. If the ripple height is abnormally high (approximately 2V or more during idling), the wires between the generator B terminal and the battery have broken due to fuse blowing, etc. The generator is usually operating properly.

For standard waveform observation conditions (Scheme 48)

Scheme 48

Scheme 48: Standard Waveform
Scheme 48: Standard Waveform

BRUSH

  1. Measure the length of the protrusion of the brush. Replace the brush if the protrusion length is shorter than the limit of 2 mm. (Scheme 49)
  2. Unsolder the lead of the brush. The brush will come out, ready for removal.
  3. Install a new brush by pushing it into the holder. (Scheme 50)

Scheme 49

Scheme 49
Scheme 49

Scheme 50

Scheme 50
Scheme 50

ROTOR

  1. Measure the resistance between the 2 slip rings of the rotor coil to check the continuity between them. Replace the rotor if the resistance is not within the standard value range of 3-5ohm. (Scheme 51)
  2. Check the continuity between the slip ring and the core. If there is continuity, replace the rotor. (Scheme 52)

Scheme 51

Scheme 51
Scheme 51

Scheme 52

Scheme 52
Scheme 52

RECTIFIER

  1. Check the condition of the positive heat sink by checking continuity between the positive heat sink and each of the stator coil lead connecting terminals. If continuity is present for both terminals, the diode is shorted. Replace the rectifier assembly. (Scheme 53)
  2. Check the condition of the negative heat sink by checking continuity between the negative heat sink and each of the stator coil lead connecting terminals. If continuity is present in both directions, the diode is shorted. Replace the rectifier assembly. (Scheme 54)
  3. Check the condition of the diode trio by testing continuity of each of the 3 diodes using a circuit tester connected to both sides of the diode. If the same reading results for both polarities, the diode is defective. Replace the rectifier assembly if any of the diodes are defective. (Scheme 55)

Scheme 53

Scheme 53
Scheme 53

Scheme 54

Scheme 54
Scheme 54

Scheme 55

Scheme 55
Scheme 55

STATOR

  1. Check the continuity between the coil lead. If there is no continuity, replace the stator. (Scheme 56)
  2. Check the continuity between the coil and the core. If there is continuity replace the stator. (Scheme 56)

Scheme 56

Scheme 56
Scheme 56

For generator removal and installation procedures (Scheme 57)

Scheme 57

Scheme 57: GENERATOR
Scheme 57: GENERATOR

Removal Service Points

  1. A) Fuel Injector, Fuel Rail, Fuel Return Pipe & Fuel Pressure Regulator Assembly Removal - After loosening the fuel rail mounting bolts, move the fuel injector, fuel rail, fuel return pipe and the fuel pressure regulator as an assembly aside in order to make room for the generator removal.
  2. B) Drive Belt Removal - Securely insert the spindle handle or ratchet handle with a 1/2" (12.7 mm) insertion angle into the jig hole of the auto-tensioner, and turn the auto-tensioner counterclockwise until it hits the stopper. (Scheme 58) Align hole A with hole B, insert an L-shaped hexagon wrench, etc. to fix and then remove the drive belt. (Scheme 59)
  3. C) Generator Removal - Raise the engine with a floor jack and remove the generator upward from the engine room.

Scheme 58

Scheme 58
Scheme 58

Scheme 59

Scheme 59
Scheme 59

For disassembly procedures (Scheme 60)

Scheme 60

Scheme 60: GENERATOR
Scheme 60: GENERATOR

Disassembly Service Points

  1. A) Front Bracket Assembly Removal - Insert the blades of screwdrivers between the front bracket assembly and stator core, and pry and separate them with the screwdrivers. (Scheme 61)
  2. B) Alternator Pulley Removal - Clamp the rotor in a vise with the pulley facing up to remove the pulley.
  3. C) Stator/Regulator Assembly Removal - Unsolder the stator leads from the main diode of the rectifier assembly when the stator is removed. When removing the rectifier assembly from the regulator assembly, undo the soldered points on the rectifier assembly. (Scheme 62)

Scheme 61

Scheme 61
Scheme 61

Scheme 62

Scheme 62
Scheme 62

Assembly Service Points

  1. A) Regulator Assembly Installation - After installing the regulator assembly, insert a wire through the hold provided on the rear bracket while pressing down on the brush, and secure the brush. (Scheme 63)
  2. B) Rotor Assembly Installation - After installing the rotor, remove the wire used to secure the brush.

Scheme 63

Scheme 63
Scheme 63

TORQUE SPECIFICATIONS

See illustration under REMOVAL & INSTALLATION or OVERHAUL .

WIRING DIAGRAMS

For wiring diagram, see STARTING/CHARGING .

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