Chapter A: General Diagnosis
24
Fig. 1-28.
Typical component locator chart.
How to Use Connector End Views
Connector end views show the cavity or terminal loca-
tions for all the most connectors shown in the system
schematic(s). The drawings show the connector's face
as seen after the harness connector has been discon-
nected from a component or mating connector. Unused
cavities are left blank in the table.
In addition, the color and part number of the connector
body is provided along with the family/series name are
often included, figure 1-29.
BATTERY SERVICE AND TESTING
Battery voltage that is out of specifications can have an
adverse effect on the electronic engine control system.
If the voltage is too low, actuators such as the fuel in-
jectors may not open far or long enough to deliver the
correct amount of fuel. As an opposite effect, when bat-
tery voltage is too high the injectors may open too far
or too long and deliver more than the designed amount
of fuel to the engine. These conditions posed a prob-
lem in the early years of electronic controls but most
modern system feature a voltage correction strategy
that corrects for the voltage variations.
Battery Testing
State-of-charge and capacity tests are performed to
determine the condition of the battery. In addition, a
preliminary evaluation on a low-maintenance or main-
tenance-free battery is required to determine if the bat-
tery is capable of accepting a recharge.
State-Of-Charge Testing
Until the appearance of sealed, maintenance-free bat-
teries, testing the specific gravity of the electrolyte with
a hydrometer was a universal method of determining
battery condition. However, the procedure can be used
today only on the minority of batteries that are unsealed
and have removable filler caps.
Some sealed maintenance-free batteries are equipped
with a built-in state-of-charge indicator in one cell. This
indicator has two functions: It shows whether electrolyte
has fallen below a minimum level and also serves as a
go/no-go hydrometer. The indicator is a plastic rod in-
serted in the top of the battery and extended into the
electrolyte. One design uses a single plastic ball, usual-
ly colored green, red, or blue, suspended in a cage from
the bottom of the rod, figure 1-30. Depending on the
specific gravity of the electrolyte, the ball will float or
sink in its cage, changing the appearance of the indica-
tor "eye."
Generally, a green dot in the indicator means the battery
is charged enough for testing. If this dot is not visible,
the battery must be charged before it is tested. If the in-
dicator eye is black and color is not visible, the battery
is below a 65 percent state-of-charge and must be
recharged before testing. If the indicator is clear or light
yellow, the electrolyte level has fallen below the bottom
of the indicator rod and attached cage. When this clear
or light yellow appearance is noted, lightly tap the top of
the indicator to dislodge any gas bubbles that might be
giving a false indication of low electrolyte level. If the
color does not change, replace the battery. Do not at-
tempt to recharge a battery if the electrolyte level is too
low.
Some battery indicators contain both a red and a green
ball. This gives the indicator a green, dark, red, and clear
appearance, in that order. The red dot indicates the bat-
tery is approaching complete discharge and must be
charged before being used. Complete indicator infor-
mation is printed on a label attached to the battery and
should be used to make an accurate interpretation of
the built-in indicator.
Summary of Contents for ASE-A8
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