DTC B1318

BHE040243000W14

Caution
• If the battery voltage drops during the inspection, B1318 will be output as a current malfunction and the proper diagnosis cannot be made. Be careful not to let the battery voltage drop.

DTC

B1318

Power supply

DETECTION CONDITION

• The voltage at DSC HU/CM terminal K is approx. 10 V or less.

POSSIBLE CAUSE

• ENGINE 15 A fuse malfunction
• Open circuit or short to ground in the wiring harness between the DSC HU/CM terminal K and the battery
• Open circuit or faulty ground in the wiring harness between the DSC HU/CM terminal T and the body ground
• Battery deterioration
• Generator malfunction
• Poor connection at connectors (female terminal)

Diagnostic procedure

STEP

INSPECTION

ACTION

1

INSPECT BATTERY VOLTAGE

• Is the battery terminal voltage normal?
Yes
Make sure that battery terminal connection is normal.
Go to the next step.
No
Charge or replace the battery, then go to Step 6.
2

INSPECT BATTERY GRAVITY

• Is 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 tensions normal?
Yes
Go to the next step.
No
Adjust the drive belt tension if necessary.
Replace the generator and/or drive belt if necessary.
4

INSPECT DSC HU/CM POWER SUPPLY FOR OPEN CIRCUIT

• Start the engine.
• Measure the voltage between DSC HU/CM terminal K and ground.
• Is the voltage above 10 V?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between DSC HU/CM and ground, then go to Step 6.
5

INSPECT DSC HU/CM GROUND FOR POOR GROUND OR OPEN CIRCUIT

• Turn the ignition switch off.
• Measure the resistance between ground and DSC HU/CM terminal T.
• 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 DSC HU/CM and ground, then go to the next step.
If resistance is not within 0-1 ohm:
• Repair or replace harness for poor ground then go to the next step.
6

VERIFY TROUBLESHOOTING COMPLETED

• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the memory.
• Is the same DTC present?
Yes
Replace the DSC HU/CM, then go to the next step.
No
Go to the next step.
7

VERIFY AFTER REPAIR PROCEDURE

• Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
DTC troubleshooting completed.