B1440 Power Mode Master Input Circuits Mismatch

OBD2 Code: B1440

Description: Power Mode Master Input Circuits Mismatch

Definition: This code indicates a discrepancy or mismatch in the power mode master input circuits, which are responsible for determining the vehicle’s power mode status (such as off, accessory, run, etc.). The issue may arise due to faulty wiring, connectors, or components within these circuits.

b1440 – Power Mode Master Input Circuits Mismatch

Typical Severity: Moderate

Common Causes

b1440 – Power Mode Master Input Circuits Mismatch

Common Causes:

• Faulty power mode master switch
• Wiring issues in the power mode master circuit
• Defective power mode master control module

Common Misdiagnosis

OBD2 Code: B1440

Description: Power Mode Master Input Circuits Mismatch

Common Misdiagnosis: Faulty ignition switch or key fob battery issues are often misdiagnosed as the cause, when in fact the problem may lie within wiring harness faults or a malfunctioning Body Control Module (BCM).

Common Diagnostic Steps

OBD2 Code: B1440
Description: Power Mode Master Input Circuits Mismatch

• Check for any stored codes that might indicate related issues.
• Inspect the ignition switch and its wiring for damage or loose connections.
• Verify the integrity of the power mode master input circuits using a multimeter.
• Examine the Body Control Module (BCM) for proper operation and signs of failure.
• Ensure all connectors are securely attached and free from corrosion or debris.
• Test the battery voltage to confirm it is within specification.
• If applicable, update the vehicle’s software to address known issues with this code.
• If necessary, replace faulty components such as switches, relays, or modules after thorough testing.