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Diagnostic Procedure

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
DTC B10A4:87 ADAPTIVE FRONT LIGHTING SYSTEM (AFS) CONTROL MODULE DIAGNOSTIC PROCEDURE

Step Inspection Action
1 INSPECT FRONT COMBINATION LIGHT (RH) CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Disconnect the front combination light (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 7.
2 INSPECT AFS CONTROL MODULE CONNECTOR CONDITION
  • Disconnect the AFS control module 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 7.
3 INSPECT SWIVEL ACTUATOR (RH) CIRCUIT FOR SHORT TO GROUND
  • Verify that the front combination light (RH) and AFS control module connectors are disconnected.
  • Inspect for continuity between the following terminals (vehicle wiring harness side) and body ground.
    • Front combination light (RH) terminal J
      • Front combination light (RH) terminal L
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • AFS control module terminal P and front combination light (RH) terminal J
  • AFS control module terminal R and front combination light (RH) terminal L

If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to ground.

Go to Step 7.
No Go to the next step.
4 INSPECT SWIVEL ACTUATOR (RH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the front combination light (RH) and AFS control module connectors are disconnected.
  • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (vehicle wiring harness side).
    • Front combination light (RH) terminal J
      • Front combination light (RH) terminal L
  • Is the voltage 0 V?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • AFS control module terminal P and front combination light (RH) terminal J
  • AFS control module terminal R and front combination light (RH) terminal L

If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to power supply.

Go to Step 7.
5 INSPECT SWIVEL ACTUATOR (RH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the front combination light (RH) and AFS control module connectors are disconnected.
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Inspect the wiring harness between the following terminals (vehicle wiring harness side) for continuity.
    • AFS control module terminal P and front combination light (RH) terminal J
      • AFS control module terminal R and front combination light (RH) terminal L
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • AFS control module terminal P and front combination light (RH) terminal J
  • AFS control module terminal R and front combination light (RH) terminal L

If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to Step 7.
6 PERFORM DTC INSPECTION AND VERIFY IF MALFUNCTIONING PART IS SWIVEL ACTUATOR (RH) Yes Replace the front combination light (RH), then go to the next step.
(See FRONT COMBINATION LIGHT REMOVAL/INSTALLATION .)
No Go to Step 8.
7 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
No Go to the next step.
8 VERIFY IF OTHER DTCs DISPLAYED
  • Are any other DTCs displayed?
 Yes Repair the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE (ADAPTIVE FRONT LIGHTING SYSTEM (AFS) CONTROL MODULE) .)
No DTC troubleshooting completed.
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