AutoCodes – Generic – B1440

B1440 Code - Power Mode Master Input Circuits Mismatch

Quick Answer

The vehicle Power Mode Master (PMM) is the Body Control Module (BCM). Common causes include Faulty Ignition Switch, Ignition Switch harness is open or shorted, Ignition Switch circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B1440 indicates Power Mode Master Input Circuits Mismatch.
Common causes: Common causes include Faulty Ignition Switch, Ignition Switch harness is open or shorted, Ignition Switch circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 38,494

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 17, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B1440 Description

The vehicle Power Mode Master (PMM) is the Body Control Module (BCM). The ignition switch is a low current switch with multiple discrete ignition switch signals to the PMM for determination of the power mode. The PMM receives the ignition switch signals, and additionally a reference voltage signal from the BCM, through the ignition switch, and back to the BCM. There are redundancies within the PMM system that can allow operation of certain subsystems when there are faults in the ignition switch circuits. Other information such as serial data input from other modules and DTCs is also used to determine what power mode signals and information is transmitted by the PMM. The BCM logic uses all this information to identify the operator's desired power mode and activate specific discrete signals, and serial data messages for the operation of different subsystems as necessary. Other modules which have switched voltage inputs may operate in a default mode if the PMM serial data message does not match what the individual module can detect from its own connections.
The PMM will activate relays and other direct outputs of the PMM as needed according to the calculated power mode. Some relays controlled by the BCM are switched ignition voltage outputs that are pass through circuits within the BCM directly from the ignition switch. If these circuits short to ground, the B+ circuit fuse to the ignition switch will open.

OBDII Code B1440 - Power Mode Master Input Circuits Mismatch - AutoCodes.com — B1440 Code - Power Mode Master Input Circuits Mismatch

What does this mean?

What are the Possible Causes of the DTC B1440?

Faulty Ignition Switch
Ignition Switch harness is open or shorted
Ignition Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B1440?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1440 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B1440 code?

Need more information on how to fix the B1440 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1440 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B1440 Buick — Power Mode Master Input Circuits Mismatch
B1440 Cadillac — Power Mode Master Input Circuits Mismatch
B1440 Chevrolet — Power Mode Master Input Circuits Mismatch
B1440 GMC — Power Mode Master Input Circuits Mismatch
B1440 Pontiac — Power Mode Master Input Circuits Mismatch
B1440 Saturn — Power Mode Master Input Circuits Mismatch

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B1440 Code

1. What are the common symptoms of OBDII code B1440, Power Mode Master Input Circuits Mismatch?

The common symptoms of OBDII code B1440 include issues with starting the vehicle, intermittent power loss, and dashboard warning lights related to the power mode.

2. What causes the OBDII code B1440 to trigger?

The OBDII code B1440 is triggered when there is a mismatch detected in the power mode master input circuits, typically due to faulty wiring, connectors, or components related to the power mode control system.

3. How serious is the OBDII code B1440, Power Mode Master Input Circuits Mismatch?

The seriousness of the OBDII code B1440 depends on the extent of the mismatch in the power mode master input circuits. Ignoring this issue can lead to potential starting problems or power loss while driving.

4. Can I still drive my vehicle with the OBDII code B1440 present?

It is not recommended to drive your vehicle with the OBDII code B1440 present, as it can lead to unexpected power-related issues and potential safety hazards on the road.

5. How can I diagnose the OBDII code B1440, Power Mode Master Input Circuits Mismatch?

Diagnosing the OBDII code B1440 typically involves inspecting the wiring, connectors, and components related to the power mode control system, as well as using a diagnostic scanner to pinpoint the exact source of the mismatch.

6. Are there any DIY repair tips for fixing the OBDII code B1440?

DIY repair tips for the OBDII code B1440 may include checking and securing the wiring connections, inspecting for any visible damage, and resetting the code to see if the issue persists.

7. Is it necessary to visit a mechanic for the OBDII code B1440 repair?

If you are not confident in diagnosing or repairing electrical issues, it is recommended to visit a qualified mechanic who can properly identify and fix the underlying cause of the Power Mode Master Input Circuits Mismatch.

8. How much does it cost to repair the OBDII code B1440?

The cost of repairing the OBDII code B1440 can vary depending on the extent of the issue and the rates of the mechanic or repair shop. It is advisable to get a few quotes from different professionals.

9. Can a faulty battery or alternator trigger the OBDII code B1440?

Yes, a faulty battery or alternator can potentially trigger the OBDII code B1440 if they are affecting the power supply or input circuits that the system relies on.

10. Will resetting the OBDII code B1440 make it go away permanently?

Resetting the OBDII code B1440 may temporarily clear the error code, but if the underlying issue causing the Power Mode Master Input Circuits Mismatch is not resolved, the code is likely to reappear.