Battery Hydrometer Displays Dark or Yellow Dot Abnormal Result
Caution: Batteries produce explosive gases. Batteries contain corrosive acid.
Batteries supply levels of electrical current high enough to cause burns.
Therefore, in order to reduce the risk of personal injury while working
near a battery, observe the following guidelines:
| • | Always shield your eyes. |
| • | Avoid leaning over the battery whenever possible. |
| • | Do not expose the battery to open flames or sparks. |
| • | Do not allow battery acid to contact the eyes or the skin. |
| - | Flush any contacted areas with water immediately and thoroughly. |
Molded into the top of the maintenance-free battery is a built-in temperature
compensated hydrometer. Make sure that the battery top is clean when observing
the hydrometer. Use a flashlight to observe the hydrometer in poorly lit areas.
Do not produce any sparks. Use this hydrometer with the following diagnostic
procedure.
Under normal operation, one of the following three indications will
be observed:
- The green dot is visible (A).
| • | Any green appearance in the hydrometer is interpreted as a green
dot. |
| • | The green dot means the battery is at least 65% charged and is
ready for testing. |
- When the green dot can not be seen (B). The charging is below
65 %.
| • | If there is a cranking complaint, refer to generator diagnosis
for further testing. |
| • | To check the charging system for excessive draw, refer to Parasitic
Load Test. |
- The dot appears clear or light yellow (C).
| • | A diagnosis can not be made at this fluid level. |
| • | A clear or light yellow dot means that the fluid level is below
the bottom of the hydrometer. |
The following can cause a low fluid condition:
A battery found with a low fluid condition can indicate a high charging
voltage, caused by a faulty charging system. The charging system must be checked
for specified output. The electrical system must be tested for a parasitic
drain. Refer to Diagnosis of the Charging System.
Replace the battery when there is a yellow or clear hydrometer along
with a cranking complaint.
Battery Hydrometer Displays Dark or Yellow Dot Normal Result
Visual Inspection
- Before performing the load test, visually inspect the battery
for obvious damage, such as a cracked or broken case.
- Repair the cause of any damage or replace the battery. Refer to
Battery Replacement
.
Hydrometer Check
- If the green dot is visible (A), perform the load test. Refer to
Battery Load Test
.
- If the green dot is not visible (B), charge the battery. Refer
to
Battery Charging
.
- If the dot is clear or yellow (C), replace the battery. Refer
to
Battery Replacement
.
