VOLTAGE REGULATION TABLE
| INSPECTION TERMINAL | VOLTAGE REGULATOR AMBIENT TEMPERATURE [°C (°F)] | STANDARD VALUE (V) |
|---|---|---|
| Terminal "S" | 20 (-4) | 14.2 - 15.4 |
| 20 (68) | 13.9 - 14.9 | |
| 60 (140) | 13.4 - 14.6 | |
| 80 (176) | 13.1 - 14.5 |
VOLTAGE REGULATION TABLE
MEASUREMENT METHOD
Connect the oscilloscope special patterns pick-up to the generator "B" terminal.
Scheme 175
STANDARD WAVEFORM
| Observation Conditions | |
|---|---|
| FUNCTION | SPECIAL PATTERNS |
| Pattern height | Variable |
| Variable knob | Adjust while viewing the wave pattern |
| Pattern selector | Raster |
| Engine revolutions | Curb idle speed |
WAVEFORM CONDITION TABLE
Scheme 176
Scheme 177
Note. The voltage waveform of the generator "B" terminal can undulate as shown in the illustration. 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 2 V 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.
ABNORMAL WAVEFORMS EXAMPLES
Note. The size of the waveform patterns can differ greatly, depending on the adjustment of the variable knob on the oscilloscope.
Note. 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.)
Note. Check the conditions of the generator malfunction light (illuminated/not illuminated) also, and carry out a total check.
Scheme 178
Scheme 179
Scheme 180
- Example 1 PROBABLE CAUSE: Open circuit or short circuit in diode
- Example 2 PROBABLE CAUSE: Open circuit in stator coil (In stator coil)
- Example 3 PROBABLE CAUSE: Open circuit in stator coil (Open circuit between stator coil and diode)
- Example 4
PROBABLE CAUSE: Short circuit in stator coil
Scheme 181
Scheme 182
PULLEY
- Set the special tool MB992226 to the pulley.
- Fix the special tool MB9922226, with the glasses wrench to prevent the rotor shaft from rotating.
- Lock the pulley when rotating it clockwise. Check that the pulley rotates smoothly when rotating it counterclockwise.
| CAUTION | Locking the one-way clutch might cause the damaged drive belt and an abnormal noise. |
Scheme 183
Scheme 184
Scheme 185
- Measure the resistance between the two 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. Standard value: 2.0 - 2.3 ohms
- Check the continuity between the slip rings and core.
- If continuity is present, replace the rotor.
Scheme 186
- Check the continuity between coil leads. If there is no continuity, replace the stator.
- Check the continuity between coil and core.
If there is continuity, replace the stator.
