John Deere stx38 - Manual (Page 155)

3/21/97
4 - 71
ELECTRICAL TESTS AND ADJUSTMENTS
PTO SWITCH TESTS
IMPORTANT: PTO switch can fail from prolonged
exposure to moisture. Original switch has seven
terminals not six. The extra terminal is not
needed for STX application.
Reason:
To make sure terminal continuity is correct in the ON
and OFF positions.
Equipment:
• Ohmmeter or Continuity Tester
Connections:
1. Put transaxle in neutral.
2. Engage park brake.
3. Put key switch in OFF position.
4. Disconnect PTO switch harness connector.
Procedure:
1. Put PTO switch in OFF position.
2. Check for continuity between terminals (A and F)
only.
3. Put PTO switch in ON position.
4. Check for continuity between terminals (B and E)
and (C and D).
Specifications:
PTO switch OFF continuity . . . . terminals (A and F)
PTO switch ON continuity
. . . . . . . . . . . . . terminals (B and E) and (C and D)
Results:
• If continuity is not to specification, replace the PTO
switch.
PTO CLUTCH TEST
Reason:
To check operation of PTO clutch coil.
Equipment:
• Jumper Wire
• Ohmmeter
Connections:
1. Put transaxle in neutral.
2. Engage park brake.
3. Put key switch in OFF position.
4. Disconnect PTO clutch connector (A).
Procedure:
1. Connect jumper wire to negative battery terminal
and PTO clutch terminal.
2. Connect jumper wire to positive battery terminal
and PTO clutch terminal.
Results:
• PTO must engage. If clutch does not engage or
does not release when power removed, perform
coil resistance test:
PTO Coil Resistance
3. Remove jumpers to PTO clutch.
4. Connect ohmmeter to PTO terminals and test
resistance of coil.
Results:
• Resistance should range between 3-10 ohms,
if not, replace the PTO clutch.
A
B
C
D E
F
M58365
A
M55948