TM 5-3805-258-24-1
9 5 0 B O P E R A T O R ’ S S T A T I O N
E L E C T R I C A L T R O U B L E S H O O T I N G
Engine Oil Pressure Indicator
Loss of engine oil pressure can cause much damage to the engine. If oil pressure
indicator turns ON, STOP MACHINE AND STOP ENGINE IMMEDIA-
TELY. Check engine oil level.
With the engine stopped and therefore no oil pressure, the oil pressure switch
must be open.
1. Remove the GY wire from the 9G8010 Engine Oil Pressure Switch and put it
to machine ground.
Indicator Turns OFF
Indicator Does NOT Turn OFF
Operator panel and harness to the switch are good.
Go to Step 2.
Go to Step 3.
2. Connect the GY wire, that connects to the oil pressure switch, to machine
ground.
Disconnect the harness plug from the operator panel and check for continuity
between Sockets 2 and 5. Socket 2 is the system ground and Socket 5 goes to the
oil pressure switch.) Use an 8S4627 Circuit Tester.
Continuity
No Continuity
The harness is good. Replace the operator panel.
Use the electrical schematic or the simplified sche-
matic to find the harness with an open (broken) wire.
Repair or replace the harness.
3. Check for continuity between the ground terminal on the oil pressure switch
(B wire) and machine ground. Use an 8S4627 Circuit Tester.
Continuity
No Continuity
The ground connection is good. Either the pressure
Repair or replace the harness or fasten a wire from
switch has a failure in the open position or there is a
the switch ground terminal to machine ground.
failure in the oil pump. Go to Step 4.
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