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Diagnostic Procedure

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DTC B1238:01 (CONNECTIVITY MASTER UNIT) - DIAGNOSTIC PROCEDURE

Step Inspection Action
1 DETERMINE MALFUNCTIONING SPEAKER Yes Go to Step 27.
No No audio produced from front door speaker (LH) and tweeter (LH)
  • Go to the next step.

    No audio produced from front door speaker (RH) and tweeter (RH)

  • Go to Step 9.

    No sound produced from rear door speaker (LH)

  • Go to Step 16.

    No audio produced from rear door speaker (RH)

  • Go to Step 21.

    No audio produced from all speakers.

  • Go to Step 26.
2 INSPECT TUNER AND AMP UNIT CONNECTOR CONDITION Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
3 INSPECT FRONT DOOR SPEAKER (LH) CONNECTOR CONDITION
  • Disconnect the front door speaker (LH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
4 INSPECT TWEETER (LH) CONNECTOR CONDITION
  • Disconnect the tweeter (LH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
5 INSPECT FRONT DOOR SPEAKER (LH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the following connectors are disconnected.
    • Tuner and amp unit
    • Front door speaker (LH)
      • Tweeter (LH)
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground.
    • Front door speaker (LH) terminal C
      • Front door speaker (LH) terminal B
  • Is there continuity?
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2A and front door speaker (LH) terminal C
  • Tuner and amp unit terminal 2C and front door speaker (LH) terminal B
  • Tuner and amp unit terminal 2A and tweeter (LH) terminal B
  • Tuner and amp unit terminal 2C and tweeter (LH) terminal A

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to ground.

Go to Step 27.
No Go to the next step.
6 INSPECT FRONT DOOR SPEAKER (LH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the following connectors are disconnected.
    • Tuner and amp unit
    • Front door speaker (LH)
      • Tweeter (LH)
  • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (wiring harness-side).
    • Front door speaker (LH) terminal C
      • Front door speaker (LH) terminal B
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2A and front door speaker (LH) terminal C
  • Tuner and amp unit terminal 2C and front door speaker (LH) terminal B
  • Tuner and amp unit terminal 2A and tweeter (LH) terminal B
  • Tuner and amp unit terminal 2C and tweeter (LH) terminal A

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to the power supply.

Go to Step 27.
7 INSPECT FRONT DOOR SPEAKER (LH) Yes Go to the next step.
No Replace the front door speaker (LH), then go to Step 27.
(See FRONT DOOR SPEAKER REMOVAL/INSTALLATION .)
8 INSPECT TWEETER (LH) Yes Go to Step 27.
No Replace the tweeter (LH), then go to Step 27.
(See TWEETER REMOVAL/INSTALLATION .)
9 INSPECT TUNER AND AMP UNIT CONNECTOR CONDITION Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
10 INSPECT FRONT DOOR SPEAKER (RH) CONNECTOR CONDITION
  • Disconnect the front door speaker (RH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
11 INSPECT TWEETER (RH) CONNECTOR CONDITION
  • Disconnect the tweeter (RH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
12 INSPECT FRONT DOOR SPEAKER (RH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the following connectors are disconnected.
    • Tuner and amp unit
    • Front door speaker (RH)
      • Tweeter (RH)
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground.
    • Front door speaker (RH) terminal C
      • Front door speaker (RH) terminal B
  • Is there continuity?
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2D and front door speaker (RH) terminal C
  • Tuner and amp unit terminal 2F and front door speaker (RH) terminal B
  • Tuner and amp unit terminal 2D and tweeter (RH) terminal B
  • Tuner and amp unit terminal 2F and tweeter (RH) terminal A

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to ground.

Go to Step 27.
No Go to the next step.
13 INSPECT FRONT DOOR SPEAKER (RH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the following connectors are disconnected.
    • Tuner and amp unit
    • Front door speaker (RH)
      • Tweeter (RH)
  • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (wiring harness-side).
    • Front door speaker (RH) terminal C
      • Front door speaker (RH) terminal B
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2D and front door speaker (RH) terminal C
  • Tuner and amp unit terminal 2F and front door speaker (RH) terminal B
  • Tuner and amp unit terminal 2D and tweeter (RH) terminal B
  • Tuner and amp unit terminal 2F and tweeter (RH) terminal A

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to the power supply.

Go to Step 27.
14 INSPECT FRONT DOOR SPEAKER (RH) Yes Go to the next step.
No Replace the front door speaker (RH), then go to Step 27.
(See FRONT DOOR SPEAKER REMOVAL/INSTALLATION .)
15 INSPECT TWEETER (RH) Yes Go to Step 27.
No Replace the tweeter (RH), then go to Step 27.
(See TWEETER REMOVAL/INSTALLATION .)
16 INSPECT TUNER AND AMP UNIT CONNECTOR CONDITION Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
17 INSPECT REAR DOOR SPEAKER (LH) CONNECTOR CONDITION
  • Disconnect the rear door speaker (LH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
18 INSPECT REAR DOOR SPEAKER (LH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the rear door speaker (LH) and tuner and amp unit connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground.
    • Rear door speaker (LH) terminal C
      • Rear door speaker (LH) terminal B
  • Is there continuity?
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2S and rear door speaker (LH) terminal C
  • Tuner and amp unit terminal 2U and rear door speaker (LH) terminal B

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to ground.

Go to Step 27.
No Go to the next step.
19 INSPECT REAR DOOR SPEAKER (LH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the rear door speaker (LH) and tuner and amp unit connectors are disconnected.
  • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (wiring harness-side).
    • Rear door speaker (LH) terminal C
      • Rear door speaker (LH) terminal B
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2S and rear door speaker (LH) terminal C
  • Tuner and amp unit terminal 2U and rear door speaker (LH) terminal B

    If there is a common connector:

    • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
    • Repair or replace the malfunctioning location.

      If there is no common connector:

    • Repair or replace the wiring harness which is shorted to the power supply.

Go to Step 27.
20 INSPECT REAR DOOR SPEAKER (LH) Yes Go to Step 27.
No Replace the rear door speaker (LH), then go to Step 27.
(See REAR DOOR SPEAKER REMOVAL/INSTALLATION .)
21 INSPECT TUNER AND AMP UNIT CONNECTOR CONDITION Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
22 INSPECT REAR DOOR SPEAKER (RH) CONNECTOR CONDITION
  • Disconnect the rear door speaker (RH) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 27.
23 INSPECT REAR DOOR SPEAKER (RH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the rear door speaker (RH) and tuner and amp unit connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground.
    • Rear door speaker (RH) terminal C
      • Rear door speaker (RH) terminal B
  • Is there continuity?
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2V and rear door speaker (RH) terminal C
  • Tuner and amp unit terminal 2X and rear door speaker (RH) terminal B

    If there is a common connector:

  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to ground.

Go to Step 27.
No Go to the next step.
24 INSPECT REAR DOOR SPEAKER (RH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the rear door speaker (RH) and tuner and amp unit connectors are disconnected.
  • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (wiring harness-side).
    • Rear door speaker (RH) terminal C
      • Rear door speaker (RH) terminal B
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit terminal 2V and rear door speaker (RH) terminal C
  • Tuner and amp unit terminal 2X and rear door speaker (RH) terminal B

    If there is a common connector:

    • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
    • Repair or replace the malfunctioning location.

      If there is no common connector:

    • Repair or replace the wiring harness which is shorted to the power supply.

Go to Step 27.
25 INSPECT REAR DOOR SPEAKER (RH) Yes Go to Step 27.
No Replace the rear door speaker (RH), then go to Step 27.
(See REAR DOOR SPEAKER REMOVAL/INSTALLATION .)
26 INSPECT TUNER AND AMP UNIT CONNECTOR CONDITION Yes Go to the next step.
No Repair or replace the connector, then go to the next step.
27 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
28 VERIFY IF OTHER DTCs DISPLAYED
  • Are any other DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [CONNECTIVITY MASTER UNIT] .)
No DTC troubleshooting completed.