DTC U1675: Lin Communication Bus 3 Error Body Control Module: 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 BODY CONTROL (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

CHECK DTC .
1. Turn the ignition switch to OFF.
2. Turn the ignition switch to ON.
3. Wait for 5 seconds.
4. Read the DTC of [Body Control] using the Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
  Is DTC U1675 displayed? (Current malfunction)
  
  Yes : Go to 2 .
  
  No : Even if DTC is displayed, the circuit has returned to a normal condition at this time.
  
  Reproduce the failure, and then perform the diagnosis again.
  
  NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
CHECK CONTROL MODULE .
1. Turn the ignition switch to OFF.
2. Disconnect the power seat Control Module connector.
3. Turn the ignition switch to ON.
4. Wait for 5 seconds.
5. Read the DTC of [Body Control] using the Subaru Select Monitor, Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
  Is DTC U1675 displayed? (Current malfunction)
  
  Yes : Go to 3 .
  
  No : Replace the power seat Control Module. Ref. to SEATS>POWER SEAT SYSTEM .
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Disconnect the body integrated unit connector.
3. Measure the resistance between the body integrated unit connector and power seat Control Module connector.
  Connector & terminal
  
  (R502) No. 18 - (B281) No. 10:
  
  Is the resistance less than 10 Ω?
  
  Yes : Go to 4 .
  
  No : Repair the open circuit of harness.
CHECK HARNESS (SHORT CIRCUIT TO POWER SUPPLY) .
Measure the voltage between power seat Control Module connector and chassis ground.

Connector & terminal

(R502) No. 18 (+) - Chassis ground (-):

Is the voltage less than 1 V?

Yes : Go to 5 .

No : Repair the short circuit to power supply in harness.
CHECK HARNESS (GROUND SHORT CIRCUIT) .
Measure the resistance between power seat Control Module connector and chassis ground.

Connector & terminal

(R502) No. 18 - Chassis ground:

Is the voltage 1 MΩ or more?

Yes : Replace the body integrated unit. Ref. to SECURITY AND LOCKS>BODY INTEGRATED UNIT .

No : Repair the ground short circuit of harness.