DTC U0131: Lost Communication with Power Steering Control Module: Procedure

1. Reconfirm DTCs.

   HINT: 

   If CAN No. 2 bus DTC U1002 is output from the power the management control ECU (Techstream display/Power Management1), troubleshoot for U1002 and check for malfunctions in the CAN No. 2 main bus circuit.

   Result

   Result	Proceed to
   U1002 is not output from power management control ECU (Techstream display/Power Management1)	A
   U1002 is output from power management control ECU (Techstream display/Power Management1)	B

B → See step   5 

A: Go to next step 

1. Turn the power switch off.
2. Disconnect the power steering ECU connector.
   Fig 1: Identifying F53 Power Steering ECU Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Power Steering ECU)

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F53-1 (CANH) - F53-7 (CANL)	Power switch off	54 to 69 Ω

NG → REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (POWER STEERING ECU) 

OK: Go to next step 

1. Turn the power switch on (IG).
2. Disconnect the power steering ECU connector.
   Fig 2: Identifying A34 Power Steering ECU Connector (Power Source Circuit)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Power Steering ECU)

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A34-2 (PGND) - Body ground	Always	Below 1 Ω

4. Measure the voltage according to the value(s) in the table below.
   Fig 3: Identifying F53 To Power Steering ECU Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   F53-6 (IG) - Body ground	Power switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Power Steering ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

OK → See step   4