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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 B1D9D-94: Error Signal Received From Rear Roof Link Motor (RH) [Retractable Hardtop Control Module] >> Diagnostic Procedure
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Diagnostic Procedure

DTC B1D9D: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 REAR ROOF LINK MOTOR (RH) CIRCUIT FOR SHORT TO POWER SUPPLY
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Disconnect the retractable hardtop control module and rear roof link motor (RH) connectors.
  • 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 (wiring harness-side):
    • Rear roof link motor (RH) terminal A
    • Rear roof link motor (RH) terminal E
  • 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:
  • Retractable hardtop control module terminal 3G and rear roof link motor (RH) terminal A
  • Retractable hardtop control module terminal 3C and rear roof link motor (RH) terminal E

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 REAR ROOF LINK MOTOR (RH)
Yes Go to the next step.
No Replace the rear roof link motor (RH), then go to the next step.
(See REAR ROOF LINK 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.