Code No. P1609: Battery Current Sensor Circuit Range/Performance <Except vehicles for Russia>


FUNCTION



  • The battery current sensor detects a battery current and inputs a signal into the engine-ECU.
  • In response to the signal, the engine-ECU controls charging and discharging.

TROUBLE JUDGMENT


Check Condition
  • Engine speed is more than 200 r/min.
Judgment Criterion
  • When there is no change in battery current sensor output voltage

FAIL-SAFE AND BACKUP FUNCTION



  • Prohibits alternator output suppression control against current consumers. (Operates as a normal alternator.)
  • The auto stop is prohibited. <Vehicles with AS&G system>

PROBABLE CAUSES



  • Battery degradation
  • Failed battery current sensor
  • Harness damage in battery current sensor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery fluid amount and specific gravity.

  • Check battery fluid amount and specific gravity (Refer to GROUP 54A - Battery - On-vehicle Service - Fluid Level and Specific Gravity Check ).

Q. Is the check result normal?
Go to Step 2 .
Repair.

STEP 2. Check battery

  • Check battery (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).

Q. Is the check result normal?
Go to Step 3 .
Replace the battery.

STEP 3. Check battery current sensor itself.

  • Check battery current sensor itself (Refer GROUP 54A - Battery - Inspection - Battery Current Sensor Check ).

Q. Is the check result normal?
Go to Step 4 .
Replace the battery current sensor.

STEP 4. Connector check: A-41 battery current sensor connector and B-27 engine-ECU connector

Q. Are the check results normal?
Go to Step 5 .
Repair or replace the connector.

STEP 5. Check harness between A-41 (terminal No. 1) battery current sensor connector and B-27 (terminal No. 99) engine-ECU connector.

  • Check power supply line for damage.

Q. Is the check result normal?
Go to Step 6 .
Repair the damaged harness wire.

STEP 6. Check harness between A-41 (terminal No. 3) battery current sensor connector and B-27 (terminal No. 101) engine-ECU connector.

  • Check earthing line for damage.

Q. Is the check result normal?
Go to Step 7 .
Repair the damaged harness wire.

STEP 7. Check harness between A-41 (terminal No. 4) battery current sensor connector and B-27 (terminal No. 100) engine-ECU connector.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 8 .
Repair the damaged harness wire.

STEP 8. M.U.T.-III diagnosis code

  • Reconfirmation of diagnosis code.

Q. Is diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).