Daewoo MATIZ, Service Manual

Page: 68 / 1184

1E – 12 ENGINE ELECTRICAL
DAEWOO M-150 BL2
BATTERY LOAD TEST
1. Check the battery for obvious damage, such as a
cracked or broken case or cover, which could permit
the loss of electrolyte. If obvious damage is noted, re-
place the battery.
Caution: Do not charge the battery if the hydrometer
is clear or light yellow. Instead, replace the battery. If
the battery feels hot or if violent gassing or spewing
of electrolyte through the vent hole occurs, discontin-
ue charging or reduce the charging rate to avoid inju-
ry.
2. Check the hydrometer. If the green dot is visible, go to
the load test procedure. If the indicator is dark but
green is not visible, charge the battery. For charging a
battery removed from the vehicle, refer to “Charging a
Completely Discharged Battery” in this section.
3. Connect a voltmeter and a battery load tester across
the battery terminals.
4. Apply a 300-ampere load for 15 seconds to remove
any surface charge from the battery.
5. Remove the load.
6. Wait 15 seconds to let the battery recover, and apply
a 270-ampere load.
Important: The battery temperature must be estimated
by touch and by the temperature condition the battery
has been exposed to for the preceding few hours.
7. If the voltage does not drop below the minimum
listed, the battery is good and should be reinstalled. If
the voltage is less than the minimum listed, replace
the battery. Refer to “Battery Specifications” in this
section.
GENERATOR OUTPUT TEST
1. Perform the generator system test. Refer to “Gener-
ator System Check” in this section.
2. Replace the generator if it fails that test. Refer to
“Generator” in the On-Vehicle Service section. If it
passes the test, perform the on-vehicle output
check which follows.
Important: Always check the generator for output be-
fore assuming that a grounded “L” terminal circuit has
damaged the regulator.
3. Attach a digital multimeter (a), an ammeter (b), and
a carbon pile load (c) to the battery (d) and the gen-
erator (e) of the rehicle.
D102E301
Important: Be sure the vehicle battery is fully charged,
and the carbon pile load is turned off.
4. With the ignition switch in the OFF position, check
and record the battery voltage.
5. Remove the harness connector from the generator.
6. Turn the ignition switch to the ON position with the
engine not running. Use a digital multimeter to
check for voltage in the harness connector “L” termi-
nal.
7. The reading should be near the specified battery
voltage of 12 volts. If the voltage is too low, check
the indicator “L” terminal circuits for open and
grounded circuits causing voltage loss. Correct any
open wires, terminal connections, etc., as neces-
sary. Refer to “Charging System” in this section.
8. Attach the generator harness connector.
9. Run the engine at a moderate idle, and measure the
voltage across the battery terminals. The reading
should be above that recorded in Step 4 but less
than 15 volts. If the reading is over 15 volts or below
the previous reading, replace the generator. Refer to
“Generator” in the On-Vehicle Service section.
10. Run the engine at a moderate idle, and measure the
generator amperage output.
11. Turn on the carbon pile, and adjust it to obtain the
maximum amps while maintaining the battery volt-
age above 13 volts.
12. If the reading is within 15 amps of the generator’s
rating noted on the generator, the generator is good.
If not, replace the generator. Refer to “Generator”
in the On-Vehicle Service section.
13. With the generator operating at the maximum out-
put, measure the voltage between the generator
housing and the battery negative terminal. The volt-
age drop should be 0.5 volt or less. If the voltage
drop is more than 0.5 volt, check the ground path
from the generator housing to the negative battery
cable.
14. Check, clean, tighten, and recheck all of the ground
connections.