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Home >> Mazda >> 2017 >> MX-5 Miata Club, Automatic Trans >> Repair and Diagnosis >> Accessories & Equipment >> Anti-Theft Systems >> On-Board Diagnostic - Retractable Fastback Control Module >> DTC B1DA7-29; Incorrect Roof Position >> Diagnostic Procedure
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Diagnostic Procedure

Step Inspection Action
1 VERIFY OTHER RETRACTABLE FASTBACK CONTROL MODULE DTCs
 Yes Replace the retractable fastback control module, then go to Step 17.
(See RETRACTABLE FASTBACK CONTROL MODULE REMOVAL/INSTALLATION ).
No Go to the next step.
2 TOP LOCK SWITCH CIRCUIT FOR OPEN CIRCUIT
  • Switch the ignition off.
  • Disconnect the negative battery cable.

    (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION ).

  • Disconnect the retractable fastback control module and top lock switch connectors.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side):
    • Retractable fastback control module terminal 1G and top lock switch terminal A
  • 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 fastback control module terminal 1G and top lock switch 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 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 17.
3 TOP LOCK SWITCH CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable fastback control module and top lock switch connectors are disconnected.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side) and body ground:
    • Top lock switch terminal B and body ground
  • 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:
  • Top lock switch terminal B and body ground

    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 17.
4 TOP LOCK SWITCH
 Yes Go to the next step.
No Replace the top lock switch, then go to Step 17.
(See TOP LOCK STRIKER REMOVAL/INSTALLATION ).
5 FRONT ROOF LINK LIMIT SWITCH (RH) CIRCUIT FOR SHORT TO GROUND
  • Disconnect the retractable fastback control module and front roof link limit switch (RH) connectors.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Front roof link limit switch (RH) terminal A
    • Front roof link limit switch (RH) terminal B
    • Front roof link limit switch (RH) terminal C
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Retractable fastback control module terminal 4B and front roof link limit switch (RH) terminal A
  • Retractable fastback control module terminal 4C and front roof link limit switch (RH) terminal B
  • Retractable fastback control module terminal 4A and front roof link limit switch (RH) terminal C

    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 17.
No Go to the next step.
6 FRONT ROOF LINK LIMIT SWITCH (RH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable fastback 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 fastback control module terminal 4B and front roof link limit switch (RH) terminal A
    • Retractable fastback control module terminal 4C and front roof link limit switch (RH) terminal B
    • Retractable fastback control module terminal 4A and front roof link limit switch (RH) terminal C
  • 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 fastback control module terminal 4B and front roof link limit switch (RH) terminal A
  • Retractable fastback control module terminal 4C and front roof link limit switch (RH) terminal B
  • Retractable fastback control module terminal 4A and front roof link limit switch (RH) terminal C

    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 17.
7 FRONT ROOF LINK LIMIT SWITCH (RH)
 Yes Go to the next step.
No Replace the front roof link limit switch (RH), then go to Step 17.
(See ROOF LINK LIMIT SWITCH REMOVAL/INSTALLATION ).
8 FRONT ROOF LINK LIMIT SWITCH (LH) CIRCUIT FOR SHORT TO GROUND
  • Disconnect the retractable fastback control module and front roof link limit switch (LH) connectors.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Front roof link limit switch (LH) terminal C
    • Front roof link limit switch (LH) terminal D
    • Front roof link limit switch (LH) terminal B
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Retractable fastback control module terminal 4L and front roof link limit switch (LH) terminal C
  • Retractable fastback control module terminal 4M and front roof link limit switch (LH) terminal D
  • Retractable fastback control module terminal 4K and front roof link limit switch (LH) terminal B

    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 17.
No Go to the next step.
9 FRONT ROOF LINK LIMIT SWITCH (LH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable fastback control module and front roof link motor (LH) connectors are disconnected.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side):
    • Retractable fastback control module terminal 4L and front roof link limit switch (LH) terminal C
    • Retractable fastback control module terminal 4M and front roof link limit switch (LH) terminal D
    • Retractable fastback control module terminal 4K and front roof link limit switch (LH) terminal B
  • 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 fastback control module terminal 4L and front roof link limit switch (LH) terminal C
  • Retractable fastback control module terminal 4M and front roof link limit switch (LH) terminal D
  • Retractable fastback control module terminal 4K and front roof link limit switch (LH) terminal B

    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 17.
10 FRONT ROOF LINK LIMIT SWITCH (LH)
 Yes Go to the next step.
No Replace the front roof link limit switch (LH), then go to Step 17.
(See ROOF LINK LIMIT SWITCH REMOVAL/INSTALLATION ).
11 REAR ROOF LINK LIMIT SWITCH (RH) CIRCUIT FOR SHORT TO GROUND
  • Disconnect the retractable fastback control module and rear roof link limit switch (RH) connectors.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Rear roof link limit switch (RH) terminal B
    • Rear roof link limit switch (RH) terminal C
    • Rear roof link limit switch (RH) terminal A
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Retractable fastback control module terminal 4A and rear roof link limit switch (RH) terminal B
  • Retractable fastback control module terminal 4E and rear roof link limit switch (RH) terminal C
  • Retractable fastback control module terminal 4D and rear roof link limit switch (RH) 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 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 17.
No Go to the next step.
12 REAR ROOF LINK LIMIT SWITCH (RH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable fastback control module and rear roof link motor (RH) connectors are disconnected.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side):
    • Retractable fastback control module terminal 4A and rear roof link limit switch (RH) terminal B
    • Retractable fastback control module terminal 4E and rear roof link limit switch (RH) terminal C
    • Retractable fastback control module terminal 4D and rear roof link limit switch (RH) terminal A
  • 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 fastback control module terminal 4A and rear roof link limit switch (RH) terminal B
  • Retractable fastback control module terminal 4E and rear roof link limit switch (RH) terminal C
  • Retractable fastback control module terminal 4D and rear roof link limit switch (RH) 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 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 17.
13 REAR ROOF LINK LIMIT SWITCH (RH)
 Yes Go to the next step.
No Replace the rear roof link limit switch (RH), then go to Step 17.
(See REAR ROOF LINK LIMIT SWITCH REMOVAL/INSTALLATION ).
14 REAR ROOF LINK LIMIT SWITCH (LH) CIRCUIT FOR SHORT TO GROUND
  • Disconnect the retractable fastback control module and rear roof link limit switch (LH) connectors.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Rear roof link limit switch (LH) terminal A
    • Rear roof link limit switch (LH) terminal B
    • Rear roof link limit switch (LH) terminal C
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Retractable fastback control module terminal 4I and rear roof link limit switch (LH) terminal A
  • Retractable fastback control module terminal 4J and rear roof link limit switch (LH) terminal B
  • Retractable fastback control module terminal 4F and rear roof link limit switch (LH) terminal C

    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 17.
No Go to the next step.
15 REAR ROOF LINK LIMIT SWITCH (LH) CIRCUIT FOR OPEN CIRCUIT
  • Verify that the retractable fastback control module and rear roof link motor (LH) connectors are disconnected.
  • Inspect the wiring harness for continuity between the following terminals (wiring harness-side):
    • Retractable fastback control module terminal 4I and rear roof link limit switch (LH) terminal A
    • Retractable fastback control module terminal 4J and rear roof link limit switch (LH) terminal B
    • Retractable fastback control module terminal 4F and rear roof link limit switch (LH) terminal C
  • 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 fastback control module terminal 4I and rear roof link limit switch (LH) terminal A
  • Retractable fastback control module terminal 4J and rear roof link limit switch (LH) terminal B
  • Retractable fastback control module terminal 4F and rear roof link limit switch (LH) terminal C

    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 17.
16 REAR ROOF LINK LIMIT SWITCH (LH)
 Yes Go to the next step.
No Replace the rear roof link limit switch (LH), then go to Step 17.
(See REAR ROOF LINK LIMIT SWITCH REMOVAL/INSTALLATION ).
17 VERIFY THAT REPAIRS HAVE BEEN COMPLETED
 Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
18 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 FASTBACK CONTROL MODULE] ).
No DTC troubleshooting completed.
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