Pickup Box Bed Sensor Inoperative

Pickup Box Bed Sensor Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information





Circuit/System Description

The bed sensor is a component of the content theft deterrent (CTD) system which monitors the status of the tailgate. The body control module (BCM) applies B+ to the bed sensor signal circuit. The bed sensor is a switch that opens and closes based on the position of the tailgate. With the switch closed, the signal circuit is switched to ground, indicating the tailgate has been opened. If the content theft deterrent (CTD) system is armed and the BCM sees the tailgate open, the CTD alarm will be activated.

Diagnostic Aids

The bed sensor is a dealer installed accessory. Not all vehicles are equipped with a bed sensor. To determine if a particular vehicle is equipped with a bed sensor, visually inspect the installation location for the sensor based on the information contain in the installation instructions.

Reference Information
Schematic Reference

Theft Deterrent System Schematics (Theft Deterrent System Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Content Theft Deterrent (CTD) Description and Operation (Content Theft Deterrent (CTD))
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the bed sensor.
2. Test for less than 10 ohms between the ground circuit terminal B and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Test for B+ between the signal circuit terminal A and ground.

• If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, test or replace the bed sensor.

Component Testing

1. Ignition OFF, disconnect the harness connector at the bed sensor.
2. With the switch open, test for infinite resistance between the signal circuit terminal A and the ground circuit terminal B.

• If not the specified value, replace the bed sensor.

3. With the switch closed, test for less then 5 ohms between the signal circuit terminal A and the ground circuit terminal B.

• If greater than the specified range, replace the bed sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Refer to Control Module References (Programming and Relearning) for BCM replacement, setup and programming