DTC B2605: Battery Control Low

DTC detecting condition:

When low voltage (9 V or less) or high voltage (16 V or more) continues for 10 seconds.

Trouble symptom:

Seat operation is possible with manual operation, but the following situations may occur.

Seat position memory registration is unable to be performed.
Memory cannot be reloaded.

Wiring diagram:

Power seat system Ref. to WIRING SYSTEM>POWER SEAT SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to POWER SEAT MEMORY (DIAGNOSTICS)>General Description>CAUTION .

CHECK DTC .
1. Turn the ignition switch to ON.
2. Read the DTC of [Power Seat Memory] using the Subaru Select Monitor. Ref. to POWER SEAT MEMORY (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is a DTC other than DTC B2605 displayed? (Current malfunction)

Yes: Perform the diagnosis for the displayed DTCs.

No: Go to 2 .
CHECK DTC .
Make sure that DTC B2605 is not displayed as past malfunction.

Is B2605 displayed? (Past malfunction)

Yes: Perform the memory recall after re-registering the memory.

No: Go to 3 .
CHECK POWER SEAT CONTROL MODULE .
Using the Subaru Select Monitor, check the following items in the [Data monitor] of [Power Seat Memory]. Ref. to POWER SEAT MEMORY (DIAGNOSTICS)>DATA MONITOR .
- Battery Voltage
Is the voltage 8 - 16 V?

Yes: Go to 5 .

No: Go to 4 .
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Disconnect the Power Seat and Remote Control Mirror control module connector.
3. Turn the ignition switch to ON.
4. Using a tester, measure the voltage between Power Seat and Remote Control Mirror control module connector and chassis ground.
  Connector and terminal
  
  (R502) No. 2 (+) - Chassis ground (-):
  
  (R502) No. 8 (+) - Chassis ground (-):
  
  (R504) No. 1 (+) - Chassis ground (-):
  
  (R504) No. 22 (+) - Chassis ground (-):
Is the voltage 8 - 16 V?

Yes: Replace Power Seat and Remote Control Mirror control module. Ref. to SEATS>POWER SEAT SYSTEM .

No: Repair the open circuit of the harness between Power Seat and Remote Control Mirror control module connector and the fuse.
CHECK BATTERY VOLTAGE .
Measure the battery voltage while the power seat is in operation.

Is the voltage 8 - 16 V?

Yes: Ask the user if the power window or passenger's power seat was operated or cranking was performed while the driver's power seat was in operation.

NOTE: Even when the battery voltage is normal under ordinary circumstance, the voltage may drop to 7.5 V or less in some cases, for example at cranking.

No: Check the battery. Ref. to STARTING/CHARGING SYSTEMS (H4DO)>BATTERY>INSPECTION .