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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 B1D99-14: Front Roof Link Motor (RH) Circuit Malfunction [Retractable Hardtop Control Module] >> Diagnostic Procedure
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Diagnostic Procedure

DTC B1D99:14 (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 6.
(See RETRACTABLE HARDTOP CONTROL MODULE REMOVAL/INSTALLATION .)
No Go to the next step.
2 VERIFY RETRACTABLE HARDTOP CONTROL MODULE POWER SUPPLY VOLTAGE
  • Measure the voltage at the following terminal (wiring harness-side):
    • Retractable hardtop control module terminal 1A
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the CABIN+B 50 A fuse, RHT R 30 A fuse.
  • Any fuse is blown:
  • Refer to the wiring diagram and verify whether or not there is a common connector between the following:
  • Retractable hardtop control module terminal 1A and battery positive terminal

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.
    • Replace the fuse.

Any fuse is damaged:
  • Replace the fuse.

All fuses are normal:
  • Refer to the wiring diagram and verify whether or not there is a common connector between the following:
  • Retractable hardtop control module terminal 1A and battery positive terminal

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 6.
3 INSPECT FRONT ROOF LINK MOTOR (RH) 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 front roof link motor (RH) connectors.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Front roof link motor (RH) terminal A
    • Front roof link motor (RH) terminal E
  • 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 3F and front roof link motor (RH) terminal A
  • Retractable hardtop control module terminal 3J and front 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 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 6.
No Go to the next step.
4 INSPECT FRONT ROOF LINK MOTOR (RH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable hardtop control module and front roof link motor (RH) connectors are disconnected.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side):
    • Retractable hardtop control module terminal 3F and front roof link motor (RH) terminal A
    • Retractable hardtop control module terminal 3J and front roof link motor (RH) terminal E
  • 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:
  • Retractable hardtop control module terminal 3F and front roof link motor (RH) terminal A
  • Retractable hardtop control module terminal 3J and front 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 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 6.
5 INSPECT FRONT ROOF LINK MOTOR (RH) Yes Go to the next step.
No Replace the front roof link motor (RH), then go to the next step.
(See ROOF LINK MOTOR REMOVAL/INSTALLATION .)
6 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
7 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.