Jeep Cherokee XJ 1999 Manual - page 11
(7) If the voltmeter reading falls below 9.6 volts, at
a minimum battery temperature of 21° C (70° F), the
battery is faulty and must be replaced.
VOLTAGE DROP TEST
The voltage drop test will determine if there is
excessive resistance in the battery terminal connec-
tions or the battery cables. When performing these
tests, it is important to remember that the voltage
drop is giving an indication of the resistance between
the two points at which the voltmeter probes are
attached.
Example: When testing the resistance of the bat-
tery positive cable, touch the voltmeter leads to the
battery positive cable clamp and the cable connector
at the starter solenoid. If you probe the battery pos-
itive terminal post and the cable connector at the
starter solenoid, you are reading the combined volt-
age drop in the battery positive cable clamp-to-termi-
nal post connection and the battery positive cable.
WARNING:
•
IF THE BATTERY SHOWS SIGNS OF FREEZ-
ING, LEAKING, LOOSE POSTS, OR LOW ELECTRO-
LYTE LEVEL, DO NOT TEST, ASSIST-BOOST, OR
CHARGE. THE BATTERY MAY ARC INTERNALLY
AND EXPLODE. PERSONAL INJURY AND/OR VEHI-
CLE DAMAGE MAY RESULT.
•
EXPLOSIVE HYDROGEN GAS FORMS IN AND
AROUND THE BATTERY. DO NOT SMOKE, USE
FLAME, OR CREATE SPARKS NEAR THE BATTERY.
PERSONAL INJURY AND/OR VEHICLE DAMAGE
MAY RESULT.
•
THE BATTERY CONTAINS SULFURIC ACID,
WHICH IS POISONOUS AND CAUSTIC. AVOID CON-
TACT WITH THE SKIN, EYES, OR CLOTHING. IN
THE EVENT OF CONTACT, FLUSH WITH WATER
AND CALL A PHYSICIAN IMMEDIATELY. KEEP OUT
OF THE REACH OF CHILDREN.
•
IF THE BATTERY IS EQUIPPED WITH REMOV-
ABLE CELL CAPS, BE CERTAIN THAT EACH OF
THE CELL CAPS IS IN PLACE AND TIGHT BEFORE
THE BATTERY IS RETURNED TO SERVICE. PER-
SONAL INJURY AND/OR VEHICLE DAMAGE MAY
RESULT FROM LOOSE OR MISSING CELL CAPS.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing the
tests, be certain the following procedures are accom-
plished:
•
The battery is fully-charged. Refer to Battery
Charging in the Service Procedures section of this
group for more information.
•
Fully engage the parking brake.
•
If the vehicle is equipped with an automatic
transmission, place the gearshift selector lever in the
Park position. If the vehicle is equipped with a man-
ual transmission, place the gearshift selector lever in
the Neutral position and fully depress the clutch
pedal.
•
Unplug the Automatic ShutDown (ASD) relay to
prevent the engine from starting. The ASD relay is
located in the Power Distribution Center (PDC). See
the label on the PDC for ASD relay identification and
location.
(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable clamp (Fig. 10). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor contact between
the cable clamp and the terminal post.
(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
clamp (Fig. 11). Rotate and hold the ignition switch
in the Start position. Observe the voltmeter. If volt-
age is detected, correct the poor contact between the
cable clamp and the terminal post.
(3) Connect the voltmeter to measure between the
battery positive terminal post and the starter sole-
noid battery terminal stud (Fig. 12). Rotate and hold
Fig. 9 Load 50% CCA Rating - Note Voltage - Typical
Load Test Temperature
Minimum Voltage
Temperature
°F
°C
9.6 volts
70° and above
21° and above
9.5 volts
60°
16°
9.4 volts
50°
10°
9.3 volts
40°
4°
9.1 volts
30°
-1°
8.9 volts
20°
-7°
8.7 volts
10°
-12°
8.5 volts
0°
-18°
XJ
BATTERY
8A - 11
DIAGNOSIS AND TESTING (Continued)