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B1405



DTC B1405

Diagnostic Instructions

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

DTC Descriptor

DTC B1405 00
- Device Voltage Reference Output 2 Circuit - Battery Current Sensor

Diagnostic Fault Information






Circuit/System Description

The battery current sensor is a 3 wire hall effect current sensor. The battery current sensor monitors the battery current. It directly inputs to the body control module (BCM). It creates a 5 volt pulse width modulation (PWM) signal of 128 Hz with a duty cycle of 0-100 percent. Normal duty cycle is between 5-95 percent. Between 0-5 percent and 95-100 percent are for diagnostic purposes.

Conditions for Running the DTC

* The ignition is ON.
* The engine is running.

Conditions for Setting the DTC

The BCM detects a duty cycle of PWM input signal is less than 5 percent or greater than 95 percent for 33 seconds.

Action Taken When the DTC Sets

The driver information center (DIC) displays the SERVICE BATTERY CHARGING SYSTEM warning message.

Conditions for Clearing the DTC

The DTC status changes to history when the battery sensed current returns to 5-95 percent for 5 seconds.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the battery current sensor.
2. Test for less than 1 ohm between the low reference circuit terminal B and ground.

^ If greater than the specified range, test the low reference circuit for an open/high. If the circuit tests normal, replace the BCM.

3. Ignition ON, test for 5 volts between the 5-volt reference circuit terminal A and ground.

^ If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Test for 5 volts between the signal circuit and ground.

^ If less than 5 volts, test the signal circuit terminal C for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the battery current sensor.

Repair Instructions

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

* Battery Current Sensor Replacement