(3) Using an multi-meter, that has least a milliam-
pere range of 200 mA. Set meter to the highest mA
range. Install meter between the battery negative
cable and battery negative post. After all modules
time-out the total vehicle IOD should be less than 35
milliamperes. If ignition off draw is more than 35
milliamperes go to Step 4.
(4) Each time the milliampere meter is discon-
nected and connected, all electronic timer functions
will be activated for approximately one minute. The
Body Control Module (BCM) ignition off draw can
reach 90 milliamperes.
(5) Remove the PDC fuses:
• Interior lamps
• Brake lamp
• IOD
(6) If there is any reading, with fuses removed
there is a short circuit in the wiring. Refer to Group
8W, wiring diagrams. Repair as necessary. If reading
is less than 35 mA go to Step 8.
(7) Install all fuses. After installing fuse, the cur-
rent can reach 90 mA. After time-out the reading
should not exceed 35 mA. If OK go to Step 9. If not,
disconnect:
• Radio
• Body control module
• Remote keyless entry module
(8) Disconnect one component at time, to see if any
component is at fault. If the high reading is not elim-
inated there is a short circuit in the wiring. Refer to
Group 8W, for wiring diagrams and circuit informa-
tion.
(9) Remove interior and brake lamp fuses. Install
the fuses. The milliampere reading should be 2-4 mA.
If reading is higher than 4 mA:
(a) Disconnect PCM.
(b) If reading is OK, replace PCM.
(c) If reading does not change, disconnect the
TCM.
(d) If reading is OK, replace TCM.
(e) If reading stays, there is a short circuit to
one of the modules. Refer to Group 8W, Wiring
Diagrams.
BATTERY LOAD TEST
A fully charged battery must have cranking capac-
ity, to provide the starter motor and ignition system
enough power to start the engine over a broad range
of ambient temperatures. A battery load test will ver-
ify the actual cranking capability of the battery.
WARNING: IF BATTERY SHOWS SIGNS OF FREEZ-
ING, LEAKING, LOOSE POSTS, OR EXCESSIVELY
LOW ELECTROLYTE LEVEL, DO NOT TEST. ACID
BURNS OR AN EXPLOSIVE CONDITION MAY
RESULT.
(1) Remove battery from vehicle. The battery top,
cables and posts should be clean. If green dot is not
visible in indicator, charge the battery. Refer to Bat-
tery Charging Procedures.
(2) Connect a Volt/Ammeter/Load tester to the bat-
tery posts (Fig. 6). Rotate the load control knob of the
Carbon pile rheostat to apply a 300 amp load. Apply
this load for 15 seconds to remove the surface charge
from the battery, and return the control knob to off
(Fig. 7).
(3) Allow the battery to stabilize for 2 minutes,
and then verify open circuit voltage.
(4) Rotate the load control knob on the tester to
maintain 50% of the battery cold crank rating for 15
seconds (Fig. 8). Record the loaded voltage reading
and return the load control to off. Refer to the Bat-
tery Specifications at the rear of this Group.
(5) Voltage drop will vary according to battery
temperature at the time of the load test. Battery
temperature can be estimated by the temperature of
exposure over the preceding several hours. If the bat-
Fig. 6 Volt-Ammeter Load Tester Connections
1 – INDUCTION AMPMETER CLAMP
2 – NEGATIVE CLAMP
3 – POSITIVE CLAMP
Fig. 7 Remove Surface Charge From Battery
8A - 6 BATTERY LH
DIAGNOSIS AND TESTING (Continued)
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