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Home >> Mazda >> 2021 >> MX-5 Miata Club, Standard Trans >> Repair and Diagnosis >> Body & Frame >> Door Locks >> On-Board Diagnostic - Retractable Fastback Control Module >> DTC B1DA9-2A: Retractable Hardtop Switch Circuit Malfunction [Retractable Hardtop Control Module] >> Diagnostic Procedure
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Diagnostic Procedure

DTC B1DA9:2A (RETRACTABLE HARDTOP CONTROL MODULE) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 VERIFY OTHER RETRACTABLE HARDTOP CONTROL MODULE DTCs
Yes Replace the retractable hardtop control module, then go to Step 4.
(See RETRACTABLE HARDTOP CONTROL MODULE REMOVAL/INSTALLATION .)
No Go to the next step.
2 INSPECT INDICATOR UNIT CIRCUIT FOR SHORT TO GROUND
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Disconnect the retractable hardtop control module and indicator unit connectors.
  • Inspect for continuity between the following terminal (wiring harness-side) and body ground:
    • Indicator unit terminal I
  • Is there continuity?
Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Retractable hardtop control module terminal 1J and indicator unit terminal I

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 4.

No Go to the next step.
3 INSPECT INDICATOR UNIT
Yes Go to the next step.
No Replace the indicator unit, then go to the next step.
(See INDICATOR UNIT REMOVAL/INSTALLATION .)
4 VERIFY THAT REPAIRS HAVE BEEN COMPLETED
Yes Repeat the inspection from Step 1.
No Go to the next step.
5 VERIFY IF OTHER DTCs DISPLAYED
  • Are any other DTCs displayed?
Yes Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [RETRACTABLE HARDTOP CONTROL MODULE] .)
No DTC troubleshooting completed.