Mazda 626 1989 Workshop Manual page 428

Number: 002/95
4. CHARGING SYSTEM DIAGNOSTIC PROCEDURE (Equipment Procedures)
1. Check the following:
• Connectors
• Grounds
• Alternator Condition
• Fuses
(USING VAT-40 OR EQUIVALENT)
2. Start engine and confirm that alternator warning light is not illuminated.
NOTE: If the warning light is illuminated, the self diagnostic function is operating. Check the alternator and related
harness. Refer to the instructions in section
3. Check the alternator belt tension and condition.
Turn the vehicle headlights "ON". Check engine belt and alternator bearing for unusual noise by raising and lower­
4.
ing the engine RPM.
5. Turn ignition and all accessories "OFF".
6. Connect a load tester.
7. Apply the load test referring to the table and flow chart on page 3 or 4 (depending on the test equipment). The final
voltage must be above the minimum value shown in the table. Record the voltage on the "Battery Check Sheet".
• If the voltage is more than the minimum, measure the open circuit voltage. Charge the battery if less than 12.4V.
• If the voltage is less than the minimum, "quick" or "boost" charge the battery for 30 minutes. Perform a load test -
again. If the battery is still below the minimum, replace the battery and proceed to step 8.
8. Start the vehicle and raise the RPM to 2500.
Connect the battery load tester and apply a load equal to the alternator rating.
9.
• If the voltage is 13.5V to 15.0V, the alternator and battery are functioning correctly.
• If the voltage is more than 15.0V, replace the alternator.
• If the voltage is 14.1V or under, check for resistance between the battery and terminals "B"
and "S". Inspect the harness for damage. Repair as necessary. Retest the alternator. If the
voltage is still less than 14.1V, replace the alternator.
(USING MIDTRONICS PowerSensor Plus TESTER)
1. Connect the MIDTRONICS PowerSensor Plus tester. If low voltage is found (less than 10.2V) charge the battery
for two (2) hours and recheck. If the voltage is greater than 10.2V, test battery condition without pre-charging. If
low voltage is still found, replace the battery according to the information in the warranty section of this bulletin.
2. If the tester indicates that the battery is not at fault, refer to the appropriate workshop manual or BETM
(Body Electrical Troubleshooting Manual) for troubleshooting and repair information.
The following are additional MIDTRONICS PowerSensor Plus tester features:
will test for an open circuit (bad cell or broken internal circuit). This is indicated by a "Red" LED light.
P osition " A "
If an open circuit is indicated, replace the battery using the criteria described in the warranty section (
of this bulletin.
a "green" LED indicates that the battery has at least 10.2V and can therefore be tested without pre-
P osition " B"
charging. This position indicates battery cold cranking amperage (CCA). This position requires that
the CCA rating be set on the MIDTRONICS PowerSensor Plus Tester dial. Refer to the attached
chart to determine CCA. The MIDTRONICS PowerSensor Plus tester then determines actual CCA
by measuring the actual condition of the battery voltage and plate condition.
measures the alternator output when the engine is started and also indicates "Open-Circuit Voltage"
P osition " C"
incilcites actual CCA condition of the battery. By comparing the indicated reading to the battery's
P osition " D"
rated CCA, the battery capacity is determined (ex. Indicated CCA of 400 for a battery with a 600
rating = the battery is 2/3 down on capacity). This decline will occur through normal aging and does
not necessarily indicate that the battery requires replacement.
S e e page 6 for the appropriate ratings.
P a g e 5 of 7
D ate Issued: 4/5 /9 5
of the applicable workshop manual.
G
Revised: