TM 10-3930-675-20-1
0012 00-4
ELECTRONIC CONTROL UNIT (ECU) INPUT VOLTAGE TROUBLESHOOTING - CONTINUED
0012 00
NOTE
ECU (790) has detected a 10V reference voltage out of range (9.3-10.4V).
Table 3. Error Code 123 - 10V Reference Voltage for Servo ECU (790) Failure Troubleshooting Procedures.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Error Code 123 - 10V Reference Voltage for
Servo ECU (790) Failure
1. Ensure that emergency stop
switch is not activated.
Release emergency stop switch
as required (TM 10-3930-675-
10).
2. Remove cab circuit breaker
panel cover and ensure that
circuit breakers F30 and F32
are not tripped.
Reset
circuit
breakers
as
required (WP 0073 00).
3. Remove servo ECU (790)
cover from operator’s seat
base and slide ECU mounting
tray out (WP 0079 00).
4. Disconnect ECU (790) con-
nectors X155 and X157.
5. Enter “DIAG SERVO 1 (13)”
menu and check voltage of
10V REF OUT. Voltage
should be 9.3-10.4V.
a. If
voltage
is
correct,
connect connector X155
and
continue
with
troubleshooting
pro-
cedure.
b. If voltage is not as
specified, check continuity
between servo ECU (790)
connector 1 in 26 and
connector X155 pin 13 and
between servo ECU (790)
connector 1 pin 27 and
connector X155 pin 12.
a. If continuity is present,
replace servo ECU (790)
(WP 0079 00).
b. If continuity is not present,
notify SRA.
DIAG SERVO
1(13)
SYSTEM POWER
24.00V
POWER RI CAN
24.00V
POWER LE CAN
24.00V
10V REF OUT
10.00V
