Tempo L4-140 2.3L CFI (1985)
Isolating the Problem
Battery, starting system, and lamp system problems can be caused by poor charging system performance. It is also possible to suspect the charging
system because of an overload in another area of the electrical system.
To avoid guesswork, it is necessary to isolate the battery, the charging system and the electrical circuits to correctly identify the area where the difficulty
lies. The best method to do this is to check the battery first before any electrical system diagnosis. The battery must be in proper state of charge and
operating properly before other areas of the electrical system can perform normally.
Battery & Charging System Check
Battery Check
The battery should be checked to see if it has capacity and ability to accept and hold a charge (Section 31-02, Batteries). If the battery is good, then the
charging system should be checked to see that it performs the function of keeping the battery charged.
The battery capacity, specific gravity and cell comparison test (non-maintenance free batteries only) will determine the ability of a battery to accept and
hold a charge. If the battery cannot meet the specifications, it should be replaced and the new battery fully charged before further diagnosis of other areas
of the electrical system.
If the battery is found to meet the required specifications, it should be fully charged before proceeding with the diagnosis of other electrical system
components.
Charging System Check
The General Charging System Test should be performed before testing any of the individual charging system components. The road map type of layout
should reduce confusion in determining "what to do next" and speed up diagnosis. The components tests will determine the type of component service
that is to be made.
The test instruments used in the General Charging System Test are a voltmeter (0-20 or 0-30 volt scale) and an ohmmeter, such as Rotunda Digital Volt/
Ohmmeter 014-00407. Special care should be given when using the ohmmeter near hot circuits. The components to be checked should be disconnected
from the circuit or the battery terminals should be disconnected.
Charging System Diagnosis
CONDITION
POSSIBLE SOURCE
RESOLUTION
^
Battery does not stay charged ^ Battery ^ Test battery, replace if necesary
-
engine starts OK ^ Loose or worn alternator belt ^ Adjust or replace belt
^
Wiring or cables ^ Service as required
^
Alternator ^ Service as required
^
Regulator ^ Replace
^
Other vehicle electrical ^ Check other systems for current systems draw, service as required
^
Alternator noisy ^ Loose or worn alternator belt ^ Adjust tension or replace belt
^
Bent pulley flanges ^ Replace pulley
^
Alternator ^ Service as required
^
Lights and/or fuses burn out ^ Sensing (A) circuit ^ Service as required frequently ^ Regulator ground
^ Service as required
^
Regulator ^ Replace
^
Alternator field circuit ^ Service as required
^
Charge indicator light flickers ^ Loose or worn alternator belt ^ Adjust tension or replace belt after engine starts or comes ^ Stator (S)
circuit ^ Service as required
on while vehicle is being
^ Lamp (1) circuit wiring inter-
^ Service as required
driven
mittent ground
^
Alternator ^ Service as required
^
Regulator ^ Replace
^
Charge indicator light on ^ Loose or worn alternator belt ^ Adjust tension or replace belt while vehicle is being driven ^ Open or
grounded wiring ^ Service as required
^
Improper wiring hook-up ^ Service or replace wiring
^
Alternator ^ Service as required
^
Regulator ^ Replace
