Description
The electrical load signal (Headlamp switch signal, rear window defogger switch signal, etc.) is transferred to ECM through the CAN communication line.
1.CHECK REAR WINDOW DEFOGGER SWITCH FUNCTION

Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to EC, "Diagnosis Procedure".
2.CHECK LIGHTING SWITCH FUNCTION
Check "LOAD SIGNAL" indication under the following conditions.

Is the inspection result normal?
YES >> GO TO 3.
NO >> Go to EC, "Diagnosis Procedure".
3.CHECK HEATER FAN CONTROL SWITCH FUNCTION
Select "HEATER FAN SW" and check indication under the following conditions

Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC, "Diagnosis Procedure".
1.INSPECTION START
Confirm the malfunctioning circuit (rear window defogger, headlamp or heater fan). Refer to EC, "Component Function Check".
Which circuit is related to the incident?
Rear window defogger>>GO TO 2
Headlamp>>GO TO 3.
Heater fan>>GO TO 4.
2.CHECK REAR WINDOW DEFOGGER SYSTEM
Perform trouble diagnosis of rear window defogger system. Refer to DEF, "Work Flow".
>> INSPECTION END
3.CHECK HEADLAMP SYSTEM
Perform trouble diagnosis of headlamp system. Refer to EXL, "Work Flow".
>> INSPECTION END
4.CHECK AIR CONDITIONING SYSTEM
Perform trouble diagnosis of air conditioning system. Refer to HA, "Workflow".
>> INSPECTION END
Engine control system
ENGINE CONTROL SYSTEM : System Diagram
NOTE:
Battery current sensor is used in CVT models.
ENGINE CONTROL SYSTEM : System Description
ECM performs various controls such as fuel injection control and ignition
timing control.
ENGINE CONTROL SYSTEM : Fail Safe
NON DTC RELATED ITEM
...
P0977 Shift solenoid B
DTC Logic
DTC DETECTION LOGIC
DTC
Trouble diagnosis name
DTC detection condition
Possible causes
P0977
Shift Solenoid B Control Circuit
High
The following diagnosis conditions
are met, and the TCM low
clutch solenoid valve current
monitor reading is 200 ...