Diagnosis Procedure
1.Check connector
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair the terminal and connector.
2.Check harness for open circuit


Is the measurement value within the specification? Yes >> go to 3.
No >> repair the bcm branch line.
3.Check power supply and ground circuit
Check the power supply and the ground circuit of the bcm. Refer to the following.
Is the inspection result normal? Yes (present error)>>replace the bcm. Refer to the following.
Yes (past error)>>error was detected in the bcm branch line.
No >> repair the power supply and the ground circuit.
AV branch line circuit
Can communication circuitPrecaution
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT
BELT PRE-TENSIONER"
The supplemental restraint system such as “air bag” and “seat belt pre-tensioner”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
P0603 ECM
DTC Logic
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
P0603
ECM BACK UP CIRCUIT
[Internal control module keep
alive memory (KAM) error]
Malfunction in the internal back up RAM o ...
Precaution
Precaution for supplemental restraint system (srs)
"air bag" and "seat belt pre-tensioner"
The supplemental restraint system such as “air bag” and “seat belt pre-tensioner”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...