Pontiac Fiero 1988 Service Manual page 407

6D3-2
CHARGING SYSTEM
Zero reading indicates open circuit between
terminal and battery. Correct as required.
Reconnect harness connector to generator,
run engine at moderate speed.
Measure voltage across battery. If above
16V, replace or repair generator.
f. Turn on accessories, load battery with
carbon pile to obtain maximum amperage.
Maintain voltage, at 13V, or above.
• If within 15 amperes of rated output,
generator is OK.
• If not within 15 amperes of rated
output, replace or repair generator.
S E R V I C E P R O C E D U R E S
CHARGING SYSTEM
The generator does not require periodic
lubrication. The rotor shaft is mounted on ball bearings
at the drive end and roller bearings at the slip ring end.
Each contains a permanent grease supply. At periodic
intervals, check mounting bolts for tightness and adjust
belt tension (see Section 6B), if applicable.
• When adjusting belt tension, apply pressure at
center of generator, never against either end
frame.
G20193-6P
Fig. 1G CS Charging System Wiring Diagram
GENERATOR BENCH CHECK-CS
To check generator in a test stand, remove as
specified in On-Car Service and proceed as follows:
1. Make connections as shown in Figure 1H, except
leave the carbon pile disconnected. The ground
polarity of generator and battery must be the
same. The battery must be fully charged. Use a
30-500 OHM resistor between battery and "L"
terminal.
2. Slowly increase generator speed and observe
voltage.
3. If the voltage is uncontrolled and increases above
16.0 volts, the rotor field is shorted, the regulator
is defective, or both. A shorted rotor field coil can
cause the regulator to become defective. NOTE:
The battery must be fully charged when making
this test.
4. If voltage is below 16.0 volts, increase speed and
adjust carbon pile to obtain maximum amperage
output. Maintain voltage above 13.0 volts.
5. If output is within 15 amperes of rated output,
generator is good.
6. If output is not within 15 amperes of rated
output, generator is defective and requires repair.