BATTERIES WILL NOT HOLD A CHARGE (cont) -624880123

TM 5-2420-222-20-1

ORGANIZATIONAL TROUBLESHOOTING - CONTINUED

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. BATTERIES WILL NOT HOLD A CHARGE - CONTINUED

WARNING

Although ignition lock switch must be on and battery ground cable connected to test electrical circuit

voltage, turn off ignition lock switch and disconnect battery ground cable before doing resistance tests or

replacing parts. This will keep you from getting shocked and prevent damage to parts and equipment.

Step 5.

Turn ignition lock switch (1) clockwise to ignition. Using multimeter set to 30 vdc scale, place red

probe on ac generator terminal (2) and black probe on ac generator terminal (3). Check for reading of

1.5 to 2.0 vdc with 55 amp ac generator or 2.0 to 3.0 with 35 amp ac generator on multimeter.

If multimeter reads as specified, go to step 6.

If multimeter does not read as specified, go to step 7.

Step 6.

Start and run engine at 1400 rpm for 15 minutes (TM 5-2420-222-10). Using thermometer and 6-inch

machinist's steel rule, measure temperature 1-inch (25.4mm) from voltage regulator (4). Using

multimeter set to 30 vdc scale, place red probe on ac generator terminal (2) and black probe on ac

generator terminal (3). Check for reading of 0.8 to 1.2 vdc plus temperature voltage correction from

chart below. Move red probe to ac generator terminal (5) and check multimeter reading. Multimeter

reading should be approximately 1 vdc less than reading obtained at ac generator terminal (2). Shut

down engine (TM 5-2420-222-10).

Temperature

Voltage

40F (4C)

14.4 - 14.9 volts

60F (16C)

14.3 - 14.7 volts

80F (27C)

14.2 - 14.6 volts

100F(38C)

14.0 - 14.4 volts

120F(49C)

13.8 - 14.3 volts

140F(60C)

13.6 - 14.1 volts

If multimeter reading is not correct at ac generator terminal (2), go to step 7.

If multimeter reading is not correct at ac generator terminal (5), replace ac generator (page

2436).

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