Generator & Regulator: Other Lexus LS II

BELT TENSION

Apply 22 lbs. (10 kg) force to top belt run. Belt tensioner should move downward, and pointer on belt tensioner should fall within area "A" (used belt) or area "B" (new belt). (Scheme 5) If pointer does not fall within specified area, replace belt or belt tensioner as necessary.

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

1. Remove battery clamp cover
2. Check battery electrolyte level check the electrolyte quantity of each cell. If under the lower level, replace the battery (or add distilled water if possible), and check the charging system.
3. Check battery voltage Measure the battery voltage between the negative (-) and the positive (+) terminals of the battery. Standard voltage: 12.2 - 12.9 V at 20° C (68° F) HINT: Before measuring the voltage, turn the ignition switch OFF and turn off the electrical systems (headlight, blower motor, rear defogger etc.) to remove the surface charge. If the vehicle has been running, wait 20 minutes or more after the vehicle stops before measuring the battery voltage. If the voltage is less than specification, charge the battery.
4. Check battery terminals and fuses Check that the battery terminals are not loose or corroded. Check the fuses for continuity.
5. Remove air cleaner inlet
6. Inspect drive belt HINT: A belt tensioner is used, so checking the belt tension is not necessary. Visually check the drive belt for excessive wear, frayed cords etc. If necessary, replace the drive belt. HINT: Cracks on the rib side of a drive belt are considered acceptable. If the drive belt has chunks missing from the ribs, it should be replaced. The drive belt tension can be released by turning the belt tensioner counterclockwise. The pulley bolt for the belt tensioner has a left-hand thread. Check the belt tensioner operation. Check that the belt tensioner moves downward when the drive belt is pressed down at the points indicated in the illustration with approx. 98 N (10 kgf, 22 lb.ft) of force. Check the alignment of the belt tensioner pulley to make sure the drive belt has not slipped off the pulley. If necessary, replace the belt tensioner. Check that the arrow mark on the belt tensioner falls within area A of the scale If it is outside area A, replace the drive belt HINT: When a new belt is installed, it should lie within area B. If not, the drive belt is not correct. After installing a belt, check that it fits properly in the ribbed grooves. Check by hand to confirm that the belt has not slipped out of the groove on the bottom of the pulley.
7. Remove oil pan protector
8. Remove engine under cover
9. Visually check generator wiring and listen for abnormal noises Check that the wiring is in good condition. Check that there is no abnormal noise from the generator while the engine is running.
10. Check charge warning light circuit warm up the engine and then turn it off. turn off all accessories. Turn the ignition switch "ON". Check that the charge warning light is lit. Start the engine. Check that the light goes off. If the light does not go off as specified, troubleshoot the charge light circuit.
11. Inspect charging circuit without load HINT: If a battery/generator tester is available, connect the tester to the charging circuit as per manufacturer's instructions. If a tester is not available, connect a voltmeter and ammeter to the charging circuit as follows: Disconnect the wire from terminal B of the generator and connect it to the negative (-) probe of the ammeter. Connect the positive (+) probe of the ammeter to terminal B of the generator. Connect the positive (+) probe of the voltmeter to terminal B of the generator. Ground the negative (-) probe of the voltmeter. Check the charging circuit as follows: With the engine running from idling to 2,000 rpm, check the reading on the ammeter and voltmeter. Standard amperage: 10 A or less Standard voltage: At 25° C (77° F): 13.7 - 14.7 V At 115° C (239° F): 13.2 - 14.0 V If the voltmeter reading is more than standard voltage, replace the voltage regulator. If the voltmeter reading is less than standard voltage, check the voltage regulator and generator as follows: With terminal F grounded, start the engine and check the voltmeter reading of terminal B. If the voltmeter reading is more than standard voltage, replace the voltage regulator. If the voltmeter reading is less than standard voltage, check the generator.
12. Inspect charging circuit with load With the engine running at 2,000 rpm, turn on the high beam headlights and place the heater blower switch at "HI". Check the reading on the ammeter. Standard amperage: 30 A or more If the ammeter reading is less than the standard amperage, repair the alternator. HINT: If the battery is fully charged, the indication will sometimes be less than standard amperage.
13. Reinstall engine under cover
14. Reinstall oil pan protector
15. Reinstall air cleaner inlet
16. Reinstall battery clamp cover

GENERATOR OUTPUT

1. Connect charging system test equipment as described in manufacturer's instructions. Check charging system output voltage at 2000 RPM. If output voltage is high, replace voltage regulator and retest. If output voltage is low, go to next step. If output voltage is correct, go to step 3). See «GENERATOR OUTPUT SPECIFICATIONS»(ref-60738-S12911172782001011800000) table.
2. If output voltage is low, by-pass regulator (full field generator) by grounding terminal "F" at back of generator. (Scheme 13) Recheck charging system output voltage. If voltage now exceeds output voltage specified in «GENERATOR OUTPUT SPECIFICATIONS»(ref-60738-S12911172782001011800000) table, replace regulator and recheck. If output voltage is still incorrect, repair or replace generator.
3. With engine at 2000 RPM, place the heater blower switch on highest setting and turn on headlights (high beam). Ammeter reading should be 30 amps or more. If amperage output is incorrect, repair or replace generator.

GENERATOR OUTPUT SPECIFICATIONS (1)

Scheme 13

BRUSHES

Check brushes for cracks and a minimum exposed length of .059" (1.5 mm). Replace brushes if damaged or worn. Brushes should slide freely in holders. Install NEW springs when replacing brushes. Solder brush wire into place.

ROTOR

1. Check rotor for open field windings by measuring resistance across slip rings. Rotor resistance should be within rotor specifications. See «ROTOR RESISTANCE SPECIFICATIONS»(ref-60738-S42688414082001011800000) table. Check rotor for short circuit to ground by connecting ohmmeter between one slip ring and rotor shaft. Continuity should not exist.
2. Check slip rings for wear or damage. Turn rotor/slip rings on lathe if necessary. Ensure slip ring diameter is not less than .504" (12.8 mm). Check bearing and replace if necessary.

ROTOR RESISTANCE SPECIFICATIONS (1)

STATOR

Using ohmmeter, check continuity between stator leads. Continuity should exist between all stator leads. Check continuity between stator lead and generator housing. Continuity should not exist. Replace stator if continuity is not as specified.