Komatsu 830E-AC Shop Manual page 828

Electrical Troubleshooting
Connect a 24VDC supply to terminal 65S on Relay Board 8, relay 5.
•
(This signals the shutters to close by bypassing the engine ECM signal.)
Be certain the A/C system is turned OFF, or disconnect wire 65T at relay 3.
•
(If 24 VDC is present at terminal 65T, shutters will not close.)
YES
Use a V.O.M.
to check for 24
VDC in circuit
65T2 at shut-
ter solenoid
valve.
Check for 24
VDC in circuit
65T1 at relay
NO
• Turn keyswitch ON
•
Turn disable switch
ON
M19-10
YES
5.
Check for 24
VDC in circuit
712ST at relay
NO
5.
Radiator Shutters
YES
YES
Check for 24
VDC in circuit
712R at relay
NO
3.
NO
Cause Remedy
Hydraulic Repair
problem hydraulic
system
Open cir- Repair
cuit open cir-
between cuit
65T1 &
65T2
Replace
Relay 5 relay 5
defective
Replace
Relay 3 relay 3
defective
Repair cir-
Open cir- cuit 712R.
cuit in
712R from
key switch
M19003