TM 5-3805-254-20-1
ORGANIZATIONAL TROUBLESHOOTING - CONTINUED
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
17. ENGINE COMPRESSION BRAKE DOES NOT WORK - CONTINUED.
WARNING
Although KEY SWITCH must be on and battery ground cable connected to test electrical circuit
voltage, turn off KEY 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 6.
Set multimeter to 20 vdc scale. Connect red test lead to output terminal (1) on COMPR BRK switch (2) and
black test lead to ground. Rotate KEY SWITCH (3) clockwise to on position and check for 11 to 13 vdc on
multimeter. Rotate KEY SWITCH (3) counterclockwise to off position. Disconnect test leads.
a.
If multimeter does not read to 11 to 13 vdc, replace COMPR BRK switch (2) (page 2-735).
b.
If multimeter reads 11 to 13 vdc, close lower center instrument panel (page 2-424) and go to step 7.
Step 7.
Set multimeter to 20 vdc scale. Connect red test lead to input terminal (4) on transmission pressure switch
(5) and black test lead to ground. Rotate KEY SWITCH (3) clockwise to on position and check for 11 to 13
vdc on multimeter. Rotate KEY SWITCH (3) counterclockwise to off position. Disconnect test leads.
a.
If multimeter does not read 11 to 13 vdc, 24A wire (6) must be replaced. Notify Direct Support Maintenance.
b.
If multimeter reads 11 to 13 vdc, go to step 8.
Step 8.
Connect jumper wire across input terminal (4) and output terminal (7) on transmission pressure switch (5).
Set multimeter to 20 vdc scale. Connect red test lead to input terminal (8) on throttle switch (9) and black
test lead to ground. Have assistant rotate KEY SWITCH (3) clockwise to on position. Check for 11 to 13
vdc on multimeter. Have assistant rotate KEY SWITCH (3) counterclockwise to off position. Disconnect
test leads.
a.
If multimeter does not read 11 to 13 vdc, 24B wire (10) must be replaced. Notify Direct Support
Maintenance.
b.
If multimeter reads 11 to 13 vdc, go to step 9.
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