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Toyota Tacoma (2015-2018) Service Manual / 2gr-fks Starting / Smart Key System(for Start Function) / Steering Lock Position Signal Circuit Malfunction (B2285)

Toyota Tacoma (2015-2018) Service Manual: Steering Lock Position Signal Circuit Malfunction (B2285)

DESCRIPTION

This DTC is stored when the steering lock position signal sent by the steering lock ECU (steering lock actuator or upr bracket assembly) via direct line and the steering lock position signal sent via LIN communication do not match.

HINT:

When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.

DTC Code

DTC Detection Condition

Trouble Area

DTC Output Confirmation Operation

B2285

The steering lock position signal sent by the steering lock ECU (steering lock actuator or upr bracket assembly) via direct line and the steering lock position signal sent via LIN communication (1-trip detection logic*) do not match.
  • AM2 NO. 2 fuse
  • Steering lock ECU (steering lock actuator or upr bracket assembly)
  • Certification ECU (smart key ECU assembly)
  • Wire harness or connector

Disconnect the cable from the negative (-) battery terminal, wait 30 seconds and then reconnect the cable to the negative (-) battery terminal. Wait 40 seconds or more with the engine switch off (with the steering wheel locked), then turn the engine switch on (ACC) (with the steering unlocked) and wait 40 seconds or more.
  • *: Only detected while a malfunction is present and the engine switch is on (IG)
Vehicle Condition and Fail-safe Function when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Function when Malfunction Detected

The engine cannot be started.

The ECU does not send an engine start request.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
  • The smart key system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting.

    Click here Troubleshoot the smart key system (for Start Function) after confirming

    Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.

  • Before replacing the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator or upr bracket assembly), refer to the smart key system (for Start Function) precaution (See page Inspect the fuses of circuits related to this system before performing ).
  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.
  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.
Related Data List and Active Test Items

DTC

Data List Item

Active Test Item

B2285

Power Source Control

Steering Unlock Switch

Smart Key

  • Power Supply Short
  • Motor Driver Short
  • Lock Bar Stuck Error

-

PROCEDURE

1.

CHECK FOR DTC (LIN COMMUNICATION SYSTEM)

(a) Check for DTCs (See page OK: ).

OK:

LIN communication system DTC B2785 is not output simultaneously.

HINT:

  • If the steering wheel cannot be locked or unlocked, the engine switch cannot be turned on (IG) and the engine cannot be started.
  • If LIN communication is not available, the steering wheel cannot be locked or unlocked.
NG

GO TO DTC B2785

OK

2.

READ VALUE USING TECHSTREAM (STEERING UNLOCK SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Power Source Control / Data List.

(e) According to the display on the Techstream, read the Data List.

Power Source Control

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Steering Unlock Switch

State of steering unlock sensor signal output from steering lock actuator assembly/ON or OFF

ON: Steering unlocked

OFF: Steering locked
  • When the shift lever is in P and the engine switch is off, if any door is opened then closed, the steering is locked.
  • When the key is inside the vehicle and the engine switch is turned on (ACC) or on (IG), the steering unlocks.
  • The engine cannot be started when the steering unlock signal is off.
Result

Result

Proceed to

Data List item does not change

A

Data List item changes

B
B

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPR BRACKET ASSEMBLY)

A

3.

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE
OK

4.

CHECK HARNESS AND CONNECTOR (GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Positive (+) tester probe → S45-4 (SLP1)

Negative (-) tester probe → Body ground

Steering locked*

10 kΩ or higher

Steering unlocked*

Below 1 Ω

HINT:

  • *: If any of the doors are opened then closed with the shift lever in P and the engine switch off, the steering wheel will be locked. If the engine switch is then turned on (ACC) or on (IG), the steering wheel will be unlocked.
  • DTC B2285 may be stored due to a malfunction in the steering lock ECU (steering lock actuator or upr bracket assembly). The steering lock position signal and unlock position signal are sent from the steering lock ECU (steering lock actuator or upr bracket assembly) to the certification ECU (smart key ECU assembly) individually.
Text in Illustration

*a

Component with harness connected

(Steering Lock ECU (steering lock actuator or upr bracket assembly))
NG

REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPR BRACKET ASSEMBLY)

OK

6.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPR BRACKET ASSEMBLY))

(a) Disconnect the C29 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the S45 steering lock ECU (steering lock actuator or upr bracket assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

C29-23 (SLP) - S45-4 (SLP1)

Always

Below 1 Ω

C29-23 (SLP) or S45-4 (SLP1) - Body ground

Always

10 kΩ or higher
OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
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