TM-9-2350-311-20-2

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; UNIT MAINTENANCE MANUAL FOR CAB, ARMAMENT, SIGHTING AND FIRE CONTROL, ELEVATING AND TRAVERSING SYSTEMS AND ASSOCIATED COMPONENTS

DECEMBER 1993

TM-9-2350-311-20-2 - Page 178 of 828

TM 9–2350–311–20–2

3–67

Go to step M.

1.

Turn MASTER switch to OFF.

2.

Reconnect wire 100 to power relay box assembly.

3.

Disconnect wire 104 at power relay box

assembly.

4.

Turn MASTER and CAB POWER switches to ON.

5.

Ensure that hydraulic pressure in power pack

main accumulator assembly is below 925 psi

(6378 kPa).

6.

Place red multimeter lead in power relay box

assembly connector for wire 104 and black lead

to ground.

7.

Check for voltage.

Is battery voltage present?

I

CONTINUED ON NEXT PAGE

POWER

RELAY BOX

ASSEMBLY

WIRE 104

CONTINUED FROM STEP H

yes

no

+–

yes

no

Repair or replace wire 100

(para 8–4). If malfunction

persists, clean contact

board segments and con-

tact arm assemblies (Chap-

ter 9).