Kohler 27EFOZ, Service Manual

Page: 34 / 80

TP-5936 7/04 22 Section 6 Controller Troubleshooting
6.3.4 Troubleshooting
Use the following flow chart as an aid in troubleshooting
the main circuit board and the entire generator set. If the prescribed remedy does not correct the problem, the
circuit board may have to be replaced.
Is 10-amp controller
circuit breaker okay?
Reset the
circuit breaker
Press the start switch
(Local or remote)
Does the engine crank?
Yes
No
Is K2 relay LED lit?
Yes
No
Is K3 relay LED lit?
Yes
No
Yes No
--Check condition/
connections of the
start/stop switch
(N, 43, and 47).
--Check the battery
condition and
connections.
--Check the connections
at P1--14.
Is K2 relay
functioning?
No
Yes
Replace
the circuit
board K3 relay or K1
relay faulty.
Replace the
circuit board
Is voltage present
at the S relay coil?
Yes
Is the K20 relay
functioning
correctly?
Is voltage present at
the S relay contact
(starter motor side)?
No
Yes
Replace the S relay
Replace
the starter
motor
Go to A
(next page)
Replace the
K20 relay Check P4--22
connection
Is voltage present at K20 relay coil?
Yes
Is K3 relay
functioning?
No
Replace
the circuit
board
No
Yes
Check the P1--4
connection
No
Yes No
Replace the circuit
board (D9 open)
Figure 6-3 Troubleshooting Relay Controller Circuit Board (1 of 4)