DTC B2275 STSW Monitor Malfunction: Wiring Diagram

WARNING: This page is about a different car, the 2006 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Wiring Diagram - STSW Monitor Malfunction

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK FOR DTCS
1. Delete the DTC (See DIAGNOSIS SYSTEM ).
  HINT:
  
  After all DTCs are cleared, turn the engine switch on (IG) and depress the brake pedal. After 15 seconds have elapsed, check if the trouble occurs again.
2. Check for DTCs again.
  OK: No DTC is output.
NG : Go to step 2

OK : CHECK INTERMITTENT PROBLEMS

CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - ECM)

Disconnect the J55 ECU connector.
Disconnect the A5 ECM connector.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection (Symbols)	Specified Condition
J55-39 (STSW) - A5-19 (STSW)	Below 1 Ω
J55-39 (STSW) or A5-19 (STSW) - Body ground	10 kΩ or higher

Fig 2: Identifying J55 Power Source Control ECU Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

OK : GO TO NEXT STEP

INSPECT ECM

Reconnect the A5 ECM connector.

Measure the voltage according to the value(s) in the table below.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
J55-39 (STSW) - Body ground	Brake pedal depressed, Engine switch START	10 to 14 V
J55-39 (STSW) - Body ground	Always	Below 1 V

Fig 3: Identifying J55 ECU Connector

HINT:

Voltage is output for 0.3 seconds after engine start.

NG : REPLACE ECM

OK : GO TO NEXT STEP

CHECK AND REPLACE POWER SOURCE CONTROL ECU
1. Temporarily replace the power source control ECU with a new or normally functioning one.
2. Delete the DTC (See DIAGNOSIS SYSTEM ).
3. Recheck for DTCs again.
  OK: No DTC is output.
NG : REPLACE ECM

OK : END (POWER SOURCE CONTROL ECU IS DEFECTIVE)