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) |
Reassembly
REASSEMBLY
PROCEDURE
1. INSTALL BRAKE MASTER CYLINDER RESERVOIR ASSEMBLY
(a) Apply a light layer of lithium soap base glycol grease to the entire circumference
of 2 new brake master cylinder reservoir grommets.
(b) Install the 2 brake master cylinder res ...
Removal
REMOVAL
CAUTION / NOTICE / HINT
HINT:
Use the same procedure for the LH side and RH side.
The following procedure listed is for the LH side.
PROCEDURE
1. REMOVE FRONT WHEEL
2. DRAIN BRAKE FLUID
NOTICE:
If brake fluid leaks onto any pa ...
Installation
INSTALLATION
CAUTION / NOTICE / HINT
HINT:
When installing new name plates and emblem, heat the vehicle body, name plates
and emblem using a heat light.
Heating Temperature
Item
Temperature
Vehicle Body
...