DTC B2782: Power Source Control ECU Malfunction: Procedure

1. Disconnect the C18 steering lock ECU connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C18-1 (GND) - Body ground	Always	Below 1 Ω

3. Reconnect the C18 steering lock ECU connector.
4. Turn the engine switch off, make sure that the steering is unlocked and move the shift lever to P (for Automatic Transaxle).
5. Check the signal waveform according to the condition(s) in the table below.
   Fig 1: Inspecting Steering Lock ECU With Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Steering Lock ECU)
   *b	Steering lock motor not operating
   *c	Steering lock motor operating

   MEASUREMENT CONDITIONS
   
   

   Item	Content
   Tester Connection	C18-3 (IGE) - C18-1 (GND)
   Tool Setting	2 V/DIV., 200 ms./DIV.
   Vehicle Condition	Steering lock motor not operating → Steering lock motor operating → Steering lock motor not operating

   HINT: 

   • When taking measurements when the lock motor is stopped, it is not necessary to perform any operations.
   • In order to take measurements when the lock motor is operating, perform either of the following operations:
     • To unlock the steering, carry the electrical key transmitter and turn the engine switch on (ACC) or on (IG) while the shift lever is in P*.
     • To lock the steering, turn the engine switch off with the shift lever in P*, and then open a door.

   *: for Automatic Transaxle

NG → See step   4 

OK: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK/CLEAR .
2. Disconnect the cable from the negative (-) battery terminal, wait for 30 seconds or more, and then reconnect the cable to the negative (-) battery terminal to clear the record of malfunctions stored in Power Supply Open in the Data List.

NEXT: Go to next step 

1. Perform the DTC output confirmation operation.
2. Check if DTC B2782 is output. Refer to DTC CHECK/CLEAR .
3. Use the Data List to check if steering lock control is functioning properly.
   SMART KEY
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Power Supply Open	Record of malfunction of signal sent to steering lock actuator assembly (motor) from power source control ECU (open circuit) (DTC B2782 stored)/OK or NG(Past)	OK: No record of malfunction (open circuit) NG(Past): Record of malfunction (open circuit) exists	This item records malfunctions in the circuit between the power source control ECU and steering lock actuator assembly (motor).

   RESULT
   
   

   Result	Proceed to
   B2782 is not output "OK" is displayed on the Techstream	A
   B2782 is output "NG (Past)" is displayed on the Techstream	B

B → See step   5 

A → SYSTEM RETURNED TO NORMAL (DTC STORED DUE TO BAD CONNECTION, BUT SYSTEM RETURNED TO NORMAL BY RECONNECTING CONNECTOR) 

1. Disconnect the C43 power source control ECU connector.
2. Disconnect the C18 steering lock ECU connector.
3. Check for deformation and corrosion of the connector case and terminals.

   OK

   There is no deformation or corrosion of the connector case or terminals.

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C43-8 (SLR+) - C18-3 (IGE)	Always	Below 1 Ω
   C43-8 (SLR+) or C18-3 (IGE) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   6