12 VDC AND 24 VDC CIRCUITS DO NOT OPERATE

TM 9-2320-366-20-1

e3. 12 VDC AND 24 VDC CIRCUITS DO NOT OPERATE

INITIAL SETUP

Equipment Conditions

Tools and Special Tools

Engine shut down (TM 9-2320-366-10-1).

Tool Kit, Genl Mech (Item 46, Appendix C)

STE/ICE-R (Item 41, Appendix C)

Materials/Parts

Multimeter, Digital (Item 22, Appendix C)

Dispenser, Pressure Sensitive Adhesive Tape

Apron, Rubber (Item 3, Appendix C)

(Item 20, Appendix D)

Goggles, Industrial (Item 15, Appendix C)

Lockwasher (Item 75, Appendix G)

Gloves, Rubber (Item 13, Appendix C)

Lockwasher (Item 83, Appendix G)

Socket Set, Socket Wrench (Item 36, Appendix C)

Lockwasher (Item 86, Appendix G)

Tester, Antifreeze and Battery (Item 42, Appendix C)

Lockwasher (Item 87, Appendix G)

Wire, Relay Test (Item 9, Appendix E)

Lockwasher (4) (Item 96, Appendix G)

Wrench, Torque, 0-175 lb-ft. (Item 58, Appendix C)

Lockwasher (2) (Item 72, Appendix G)

Wrench, Torque, 0-200 lb-in. (Item 59, Appendix C)

Self-locking Nut (Item 167, Appendix G)

Ties, Cable, Plastic (Item 69 Appendix D)

References

Wire, Elect, 50 ft (Item 71, Appendix D)

TM 9-6140-200-14

TM 9-4910-571-12&P

Personnel Required

(2)

KNOWN INFO

TEST OPTIONS

NOTE

Circuit breaker CB70 OK.

Battery Specific Gravity Test

Perform electrical troubleshooting e1.

Circuit Breaker Does Not Operate on circuit

POSSIBLE PROBLEMS

REASON FOR QUESTION

breaker CB70 prior to beginning this task.

Faulty battery(ies).

If battery(ies) is unserviceable,

Faulty cab to chassis ground

12 vdc circuits will not operate.

strap.

START

Faulty PDP to cab ground cable.

Faulty dashboard cable assembly.

Faulty shunt.

Faulty starter to shunt 24 VDC

WARNING

cable.

Read WARNING

Faulty battery to shunt cable

on following page.

assembly.

Faulty starter to chassis ground

cable.

Are batteries serviceable?

Faulty 100 AMP reverse polarity

relay.

Faulty battery to 100 AMP

reverse polarity relay 12 VDC

cable.

Faulty 100 AMP reverse polarity

relay to PDP 12 VDC cable.

Faulty 200 AMP reverse polarity

relay.

Faulty 200 AMP terminal block.

Faulty 200 AMP terminal block

Charge battery(ies)

to PDP 12 VDC cable.

(TM 9-6140-200-14) or

YES

Faulty 200 AMP terminal block

replace battery(ies)

to reverse polarity relay 12 VDC

(para 7-55).

load cable.

Faulty 200 AMP terminal block

to reverse polarity relay 12 VDC

battery cable.

Faulty battery to 200 AMP

terminal block 12 VDC cable

assembly.

2-264

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