DTC B1318

id060200809400

DTC B1318
Battery power supply
DETECTION CONDITION
•  Voltage of 9 V or less detected by EHPAS CM internal battery voltage observation.
POSSIBLE CAUSE
•  Battery and/or generator malfunction
•  EHPAS 80A fuse malfunction
•  Open or short circuit in wiring harness between EHPAS CM terminal 1B and battery
•  Open or short circuit in wiring harness between EHPAS CM terminal 1A and body ground
SYSTEM WIRING DIAGRAM

Diagnostic procedure

STEP

INSPECTION

ACTION
1
INSPECT BATTERY VOLTAGE
•  Is the battery terminal voltage normal?
Yes
Make sure that battery terminal connection is okay.
Go to the next step.
No
Charge or replace the battery, then go to Step 6.
2
INSPECT BATTERY GRAVITY
•  Is the battery specific gravity as specified?
Yes
Go to the next step.
No
Replace the battery, then go to Step 6.
3
INSPECT CHARGING SYSTEM
•  Are the generator and drive belt tension normal?
Yes
Go to the next step.
No
Replace the generator and/or drive belt if necessary.
Go to step 6.
4
INSPECT EHPAS CM POWER SUPPLY CIRCUIT FOR OPEN OR SHORT CIRCUIT
•  Start the engine.
•  Measure the voltage between following EHPAS CM terminal (wiring harness-side) and ground.
―  EHPAS CM: 1B—ground
•  Is the voltage 9 V or more?
Yes
Go to the next Step.
No
Repair or replace the wiring harness (including fuse) between the EHPAS CM and ground, then go to Step 6.
5
INSPECT EHPAS CM GROUND CIRCUIT FOR POOR GROUND OR OPEN CIRCUIT
•  Switch the ignition OFF (LOCK).
•  Measure the resistance between the following EHPAS CM terminal (wiring harness-side) and ground.
―  EHPAS CM: 1A—ground
•  Is the resistance within 0—1 ohm?
Yes
Go to the next step.
No
If there is no continuity:
•  Repair or replace the wiring harness for open circuit between the EHPAS CM and ground, then go to the next step.
If the resistance is not within 0—1 ohm:
•  Repair or replace the wiring harness for poor ground, then go to the next step.
6
VERIFY THAT THE SAME DTC IS NOT PRESENT
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the memory.
•  Is the same DTC present?
Yes
Replace the electric power steering oil pump component, then go to the next step.
(See ELECTRIC POWER STEERING OIL PUMP COMPONENT REMOVAL/INSTALLATION.)
No
Go to the next step.
7
VERIFY THAT NO OTHER DTCS ARE PRESENT
•  Are any other DTCs output?
Yes
Go to the applicable DTC inspection.
(See ELECTRO HYDRAULIC POWER ASSIST STEERING (EHPAS) ON-BOARD DIAGNOSIS.)
No
DTC troubleshooting completed.