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For 1990-2009 cars only

Circuit Description

The folding top stowage compartment lid cylinder position sensor is a hall effect sensor mounted on the folding top stowage compartment lid cylinder. The folding top stowage compartment lid latch sensors are two hall effect sensors wired in parallel and are part of the folding top stowage compartment latch assembly. The hall sensors are supplied with a 12-volt reference signal from the roof door module (RDM). When the folding top stowage compartment lid cylinder reaches full travel, the folding top stowage compartment lid cylinder position sensor will be active sending a voltage signal between 0.35 and 1.33 volts to the RDM. When the folding top stowage compartment lid is in the closed position, the folding top stowage compartment lid latch sensors will be active sending a voltage signal between 0.82 and 1.80 volts to the RDM. The RDM monitors the folding top stowage compartment lid position sensor and folding top stowage compartment lid latch sensors at least once every 200 milliseconds.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3666 Rear Tonneau Position Error

Conditions for Running the DTC

    • The battery voltage is between 9-16 volts.
    • Ignition is in the Accessory or Run position or retained accessory power (RAP) is active.
    • A request for folding top operation has been received by the RDM, and the RDM attempts to operate the folding top.

Conditions for Setting the DTC

    • If the RDM detects the folding top stowage compartment lid position sensor signal circuit or folding top stowage compartment lid latch sensor circuit is shorted to power.
    • If the RDM detects the folding top stowage compartment lid position sensor signal circuit or folding top stowage compartment lid latch sensor circuit is shorted to ground or open.
    • If the RDM detects the folding top stowage compartment lid position sensor 12-volt reference is open or shorted to ground.

Action Taken When the DTC Sets

    • Stores a current DTC B3666 in the RDM.
    • DTCs B1310, B1311, B3665, and B3667 will also be set in history when the folding top stowage compartment lid cylinder position sensor signal is shorted to voltage.
    • The folding top operation is suspended.

Conditions for Clearing the DTC

    • This DTC will clear on the current status after the condition for setting the fault is corrected.
    • A history DTC will clear after 50 consecutive ignition cycles without a fault present.
    • History and current DTC can be cleared using the scan tool.

Diagnostic Aids

The code that is set as current should be diagnosed first due to multiple codes set in history.

If the DTC does not reset after the code is cleared, then the sensor may be the source of an intermittent fault. Refer to Testing for Intermittent Conditions and Poor Connections .

Step

Action

Yes

No

Schematic Reference: Folding Top Schematics

Connector End View Reference: Power Roof Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Manually move the folding top storage lid to the up and down positions. Refer to Folding Top Manual Operation if necessary.
  2. With a scan tool, observe the Storage Lid Closed Left/Right Sensors Data Parameter in the Open/Short Data List for each position. Refer to Scan Tool Data List and Scan Tool Data Definitions for typical values and definitions.

Does the scan tool display the appropriate data in the each position?

Go to Step 3

Go to Step 4

3

  1. Manually move the folding top storage lid to the up and down positions. Refer to Folding Top Manual Operation if necessary.
  2. With a scan tool, observe the Storage Lid Cyl. Extended Sen. Data Parameter in the Open/Short Data List for each position. Refer to Scan Tool Data List and Scan Tool Data Definitions for typical values and definitions.

Does the scan tool display the appropriate data in the each position?

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the affected folding top stowage compartment lid latch sensor or folding top stowage compartment lid cylinder position sensor.
  3. Connect a test lamp to a good ground.
  4. Test the 12-volt reference circuit at the affected folding top stowage compartment lid latch sensor or folding top stowage compartment lid cylinder position sensor.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

5

With the test lamp connected to a good ground, test the affected folding top stowage compartment lid latch sensor signal circuit or folding top stowage compartment lid cylinder position sensor signal circuit.

Does the test lamp illuminate?

Go to Step 10

Go to Step 6

6

Test the affected folding top stowage compartment lid latch sensor signal circuit or folding top stowage compartment lid cylinder position sensor signal circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 8

7

Test the 12-volt reference circuit at the affected folding top stowage compartment lid latch sensor or folding top stowage compartment lid cylinder position sensor for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 9

8

Inspect for poor connections at the harness connector of the affected folding top stowage compartment lid latch sensor or folding top stowage compartment lid cylinder position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 11

9

Inspect for poor connections at the harness connector of the RDM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 12

10

Repair the short to battery voltage in the affected folding top stowage compartment lid latch sensor signal circuit or folding top stowage compartment lid cylinder position sensor signal circuit. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 13

--

11

Replace the inoperative folding top stowage compartment lid latch sensor or folding top stowage compartment lid cylinder position sensor. Refer to Folding Top Stowage Compartment Lid Latch Replacement or Folding Top Stowage Compartment Lid Hydraulic Cylinder Replacement .

Did you complete the replacement?

Go to Step 13

--

12

  1. Replace the RDM. Refer to Control Module References for replacement, setup, and programming.
  2. Perform the reinitialization of the power windows procedure for the RDM. Refer to Power Window Reinitialization .

Did you complete the replacement?

Go to Step 13

--

13

  1. Use the scan tool in order to clear the DTCs .
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK