VARIABLE GEAR RATIO STEERING SYSTEM, Diagnostic DTC:C15A1, C15A2, C15A6

DTC Code DTC Name
C15A1 Short in Motor Circuit
C15A2 Open in Motor Circuit
C15A6 Actuator Motor Power Distribution Malfunction

DESCRIPTION

If the VGRS ECU (front steering control ECU) detects excessive current, it stores DTC C15A1, turns on the master warning light.

If the VGRS ECU (front steering control ECU) detects excessive current flowing into the steering actuator assembly or an internal malfunction, it turns the master warning light on, and stores DTC C15A2.

If the VGRS ECU (front steering control ECU) detects a malfunction in the motor drive circuit, it turns the master warning light on, and stores DTC C15A6.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Return-to-normal Condition
C15A1 Short in Motor Circuit

Either condition is met:


  • After the power switch is turned on (IG), a short in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 1.2 seconds or more before control starts.

  • After the power switch is turned on (IG), a short in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 0.03 seconds or more.

  • Steering actuator assembly

  • VGRS ECU (front steering control ECU)

  • Harness or connector

 Comes on Power switch on (IG) again
C15A2 Open in Motor Circuit

Either condition is met:


  • After the power switch is turned on (IG), an open in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 1.2 seconds or more before control starts.

  • After the power switch is turned on (IG), an open in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 0.03 seconds or more.

  • Steering actuator assembly

  • VGRS ECU (front steering control ECU)

  • Harness or connector

 Comes on Power switch on (IG) again
C15A6 Actuator Motor Power Distribution Malfunction

Either condition is met:


  • After the power switch is turned on (IG), an open in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 1.2 seconds or more before control starts.

  • After the power switch is turned on (IG), an open in the motor circuit or an internal ECU (motor drive circuit) malfunction continues for approximately 0.03 seconds or more.

  • Steering actuator assembly

  • VGRS ECU (front steering control ECU)

  • Harness or connector

 Comes on Power switch on (IG) again
DTC Detection Conditions: C15A1
Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4
Diagnosis Condition After the power switch is turned on (IG) and before control starts ○ ○ - -
After the power switch is turned on (IG) - - ○ ○
Malfunction Status A short in the motor circuit ○ - ○ -
An internal ECU (motor drive circuit) malfunction - ○ - ○
Detection Time Approximately 1.2 seconds or more Approximately 1.2 seconds or more Approximately 0.03 seconds or more Approximately 0.03 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

DTC Detection Conditions: C15A2
Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4
Diagnosis Condition After the power switch is turned on (IG) and before control starts ○ ○ - -
After the power switch is turned on (IG) - - ○ ○
Malfunction Status An open in the motor circuit ○ - ○ -
An internal ECU (motor drive circuit) malfunction - ○ - ○
Detection Time Approximately 1.2 seconds or more Approximately 1.2 seconds or more Approximately 0.03 seconds or more Approximately 0.03 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

DTC Detection Conditions: C15A6
Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 2
Diagnosis Condition After the power switch is turned on (IG) and before control starts ○ ○ - -
After the power switch is turned on (IG) - - ○ ○
Malfunction Status An open in the motor circuit ○ - ○ -
An internal ECU (motor drive circuit) malfunction - ○ - ○
Detection Time Approximately 1.2 seconds or more Approximately 1.2 seconds or more Approximately 0.03 seconds or more Approximately 0.03 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

B004T1TE16

CAUTION / NOTICE / HINT

Note


  • When replacing the VGRS ECU (front steering control ECU) or steering actuator assembly, perform actuator angle neutral point calibration and initialization after replacing parts.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

When DTC C15A2 is output, a short circuit inside the steering actuator assembly or inside the VGRS ECU (front steering control ECU) is suspected.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (PIG, PGND TERMINAL)


    1. B004R1SC67
      *a

      Component with harness connected

      (VGRS ECU [Front Steering Control ECU])

      Turn the power switch off.

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

      Tech Tips

      Perform the inspection from the rear of the connector with the connector connected to the VGRS ECU (front steering control ECU).

      Standard Resistance
      Tester Connection Condition Specified Condition
      A20-1(PGND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A20-2(PIG) - A20-1(PGND) Power switch off 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT STEERING ACTUATOR ASSEMBLY


    1. Disconnect the G77 VGRS ECU (front steering control ECU) connector.

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

      Tech Tips

      Measure the resistance of the steering actuator assembly at the connector of the VGRS ECU (front steering control ECU).

      Standard Resistance
      Tester Connection Condition Specified Condition
      G77-2 (BMV) - G77-3 (BMU) Always Below 1 Ω
      G77-2 (BMV) - G77-1 (BMW) Always Below 1 Ω
      G77-3 (BMU) - G77-1 (BMW) Always Below 1 Ω
      G77-1 (BMW) - Body ground Always 100 kΩ or higher
      G77-2 (BMV) - Body ground Always 100 kΩ or higher
      G77-3 (BMU) - Body ground Always 100 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (VGRS ECU (FRONT STEERING CONTROL ECU) - STEERING ACTUATOR ASSEMBLY) Click here

    OK

  3. RECONFIRM DTC


    1. Reconnect the G77 VGRS ECU (front steering control ECU) connector.

    2. Clear the DTCs.

      Click here


      Chassis > VGRS > Clear DTCs

    3. Turn the power switch on (READY).

    4. Check for DTCs.

      Click here


      Chassis > VGRS > Trouble Codes
      Result
      Result Proceed to
      DTCs C15A1, C15A2 and C15A6 are not output A
      DTCs C15A1, C15A2 or C15A6 is output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE VGRS ECU (FRONT STEERING CONTROL ECU) Click here

  4. CHECK HARNESS AND CONNECTOR (VGRS ECU (FRONT STEERING CONTROL ECU) - STEERING ACTUATOR ASSEMBLY)


    1. Turn the power switch off.

    2. Disconnect the G77 VGRS ECU (front steering control ECU) connector.

    3. Disconnect the G33 steering actuator assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G77-2 (BMV) - G33-5 (BMV+) Always Below 1 Ω
      G77-3 (BMU) - G33-4 (BMU+) Always Below 1 Ω
      G77-1 (BMW) - G33-13 (BMW+) Always Below 1 Ω
      G77-2 (BMV) - G77-3 (BMU) Always 100 kΩ or higher
      G77-2 (BMV) - G77-1 (BMW) Always 100 kΩ or higher
      G77-3 (BMU) - G77-1 (BMW) Always 100 kΩ or higher
      G77-2 (BMV) or G33-5 (BMV+) - Body ground Always 100 kΩ or higher
      G77-3 (BMU) or G33-4 (BMU+) - Body ground Always 100 kΩ or higher
      G77-1 (BMW) or G33-13 (BMW+) - Body ground Always 100 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE STEERING ACTUATOR ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR