Mitsubishi Electric Lancer Evolution-VII Workshop Manual page 1187

13A-50
Code No. P1603 Battery backup line malfunction
Inspection Range
D Ignition switch: ON
Evaluation Conditions
D The backup RAM information set at the last time when the ignition switch
was turned to the OFF position is not memorized.
Is the battery terminal disconnected
before reading the diagnostic trouble
code?
NO
Measure at the C-115 engine-ECU
connector.
D Disconnect the connector to
measure at the harness side.
D Voltage between terminal No.80
and earth.
OK: System voltage
OK
Check the following connector:
C-115
OK
Check the trouble symptoms.
NG
Replace the engine-ECU
MPI -
Troubleshooting
YES
Turn the ignition switch to the
"LOCK"(OFF) position and then in 10
seconds turn the ignition switch to the
"ON" position
MUT-II Self-Diag code
D Diagnosis codes No. P1603 is
output.
NG
Check the following connector:
C-129, C-05, C-135
Check and repair the harness
between battery and engine-ECU.
D Check for disconnection and
short-circuit of the power cable.
NG
Repair
OK
Intermittent Malfunction (Refer to
GROUP 00 - Points to Note for
Intermittent Malfunction.)
Probable cause
D Battery backup line disconnection, short circuit or
connector contact defect
D Engine-ECU malfunction
NO
NG
OK
End
Repair