AutoCodes – Cadillac – B1440 Cadillac

B1440 Cadillac 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 Cadillac 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.

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Code Popularity 2,731

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

What does this mean?

What are the Possible Causes of the DTC B1440 Cadillac?

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 Cadillac?

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 Cadillac 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.

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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 Cadillac Code

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

- Common symptoms include issues with starting the vehicle, intermittent power loss, engine stalling, and warning lights on the dashboard.

2. What can cause the OBDII code B1440 in a Cadillac?

- The code B1440 "Power Mode Master Input Circuits Mismatch" in a Cadillac can be caused by faulty wiring, damaged connectors, or a malfunctioning power mode control module.

3. How do I diagnose the OBDII code B1440 in my Cadillac?

- Diagnosing the B1440 code involves using an OBDII scanner to retrieve the code, checking the wiring and connectors for any damage, and testing the power mode control module for proper functionality.

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

- It is not recommended to drive your Cadillac with the B1440 code present, as it can lead to potential safety hazards and further damage to the vehicle.

5. How can I repair the OBDII code B1440 in my Cadillac?

- Repairing the B1440 code may involve repairing or replacing damaged wiring and connectors, as well as replacing the power mode control module if necessary.

6. Are there any DIY tips for fixing the B1440 code in a Cadillac?

- DIY tips for fixing the B1440 code include checking for loose connections, inspecting wiring for damage, and ensuring all components are securely in place.

7. Will resetting the OBDII code B1440 in my Cadillac make it go away permanently?

- Resetting the B1440 code may temporarily clear the warning light, but if the underlying issue is not fixed, the code is likely to reappear.

8. Can a mechanic help me fix the OBDII code B1440 in my Cadillac?

- Yes, a qualified mechanic can help diagnose and repair the B1440 code in your Cadillac to ensure proper functioning of the power mode master input circuits.

9. How much does it cost to repair the OBDII code B1440 in a Cadillac?

- The cost of repairing the B1440 code can vary depending on the extent of the damage, parts needed for replacement, and labor costs charged by the mechanic or dealership.

10. Is the OBDII code B1440 in a Cadillac a common issue?

- The B1440 code may not be a common issue, but it is important to address it promptly to prevent further damage and ensure the vehicle's safety and performance.