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Home >> Mazda >> 2023 >> MX-5 Miata Club >> Repair and Diagnosis >> Body & Frame >> Door Locks >> On-Board Diagnostic - Retractable Fastback Control Module >> DTC B1DA1-94: Error Signal Received From Top Lock Motor [Retractable Hardtop Control Module] >> Diagnostic Procedure
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Diagnostic Procedure

DTC B1DA1:94 (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 TOP LOCK MOTOR CIRCUIT FOR SHORT TO POWER SUPPLY  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:
  • Retractable hardtop control module terminal 2B and top lock motor terminal E
  • Retractable hardtop control module terminal 2F and top lock motor terminal A

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 4.
3 INSPECT TOP LOCK MOTOR  Yes Go to the next step.
No Replace the top lock motor, then go to the next step. (See TOP LOCK MOTOR 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.