DESCRIPTION
Detection Item |
Symptom |
Trouble Area |
---|---|---|
Certification ECU Communication Stop Mode |
Either condition is met:
|
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
NOTICE:
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DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.
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HINT:
PROCEDURE
1. |
CHECK FOR OPEN IN CAN BUS LINES (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) BRANCH LINE) |
(a) Disconnect the cable from the negative (-) battery terminal.
(b) Disconnect the certification ECU (smart key ECU assembly) connector. |
|
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
C29-7 (CANH) - C29-8 (CANL) |
Cable disconnected from negative (-) battery terminal |
54 to 69 Ω |
*a |
Front view of wire harness connector (to Certification ECU (Smart Key ECU Assembly)) |
NG | ![]() |
REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) |
|
2. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) |
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
(b) Connect the cable to the negative (-) battery terminal.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
C29-10 (+B) - Body ground |
Always |
11 to 14 V |
*a |
Front view of wire harness connector (to Certification ECU (Smart Key ECU Assembly)) |
OK | ![]() |
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) |
Lost Communication with ECM (C1437)
DESCRIPTION
The skid control ECU (brake actuator assembly) receives signals from the ECM
via the CAN communication system.
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
C1437
Lost Communication with ECM
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System Diagram
SYSTEM DIAGRAM
Communication Table
Transmitting ECU (Transmitter)
Receiving ECU (Receiver)
Signal
Line
Certification ECU
(Smart Key ECU Assembly)
Main Body ECU
(Multiplex Network Body ECU)
...