DESCRIPTION
This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and power management control ECU stops for more than 10 seconds.
DTC Code |
DTC Detection Condition |
Trouble Area |
---|---|---|
B278C |
No communication between the certification ECU (smart key ECU assembly) and power management control ECU for more than 10 seconds. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Connect the Techstream to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the Techstream and vehicle begins.
PROCEDURE
1. |
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY AND BODY GROUND) |
(a) Disconnect the D43 ECU connector. |
|
(b) Measure the resistance and voltage according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
D43-5 (GND2) - Body ground |
Always |
Below 1 Ω |
D43-6 (GND) - Body ground |
Always |
Below 1 Ω |
Standard Voltage:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
D43-1 (AM22) - Body ground |
Always |
11 to 14 V |
D43-2 (AM21) - Body ground |
Always |
11 to 14 V |
*1 |
Power Management Control ECU |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
2. |
CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER MANAGEMENT CONTROL ECU) |
(a) Disconnect the D25 ECU connector. |
|
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
D25-29 (LIN) - D43-24 (LIN2) |
Always |
Below 1 Ω |
D25-29 (LIN) - Body ground |
Always |
10 kΩ or higher |
*1 |
Front view of wire harness connector (to Certification ECU (Smart Key ECU Assembly)) |
*2 |
Front view of wire harness connector (to Power Management Control ECU) |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
3. |
REPLACE POWER MANAGEMENT CONTROL ECU |
(a) Replace the power management control ECU (See page
).
|
4. |
CHECK DTC OUTPUT |
(a) Clear the DTC (See page ).
(b) Recheck for DTCs.
OK:
DTC B278C is not output.
OK | ![]() |
END (POWER MANAGEMENT CONTROL ECU WAS DEFECTIVE) |
NG | ![]() |
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) |
Removal
REMOVAL
CAUTION / NOTICE / HINT
NOTICE:
Do not replace the spiral cable with the battery connected and the ignition
switch ON.
Do not rotate the spiral cable without the steering wheel with the battery
connected and the ignition switch O ...
Wheels
If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause loss of handling control.
- Wheel selection
When replacing wheels, care should be taken to ensure that they are equivalent ...
Precaution
PRECAUTION
1. TROUBLESHOOTING PRECAUTION
NOTICE:
Be sure to read the supplemental restraint system precautions thoroughly
before servicing the brake system (See page
).
Care must be taken to replace each part properly as it could affect ...