AutoCodes – Cadillac – U0420 Cadillac

U0420 Cadillac Code - Invalid Data Received From Power Steering Control Module

Quick Answer

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Common causes include Faulty Power Steering Control Module, Power Steering Control Module harness is open or shorted, Power Steering Control Module 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: U0420 Cadillac indicates Invalid Data Received From Power Steering Control Module.
Common causes: Common causes include Faulty Power Steering Control Module, Power Steering Control Module harness is open or shorted, Power Steering Control Module 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 2,789

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 Apr 12, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0420 Cadillac Description

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Operating information and commands are exchanged among the devices. The devices have programmed information about what messages are needed to be exchanged on the serial data circuits. Some devices are constantly receiving information from other devices through serial data communication network. The invalid data Diagnostic Trouble Code (DTC) will be set when a receiving device detects a discrepancy in the information it receives from the Power Steering Control Module causing its integrity to be questioned.

OBDII Code U0420 Cadillac - Invalid Data Received From Power Steering Control Module - AutoCodes.com — U0420 Cadillac Code - Invalid Data Received From Power Steering Control Module

What does this mean?

What are the Possible Causes of the DTC U0420 Cadillac?

Faulty Power Steering Control Module
Power Steering Control Module harness is open or shorted
Power Steering Control Module circuit poor electrical connection

How to Fix the DTC U0420 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 U0420 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 U0420 Cadillac Code

1. What are common symptoms of the U0420 OBDII code in a Cadillac indicating invalid data received from the power steering control module?

Possible symptoms include loss of power steering assist, illuminated warning lights on the dashboard (such as the power steering light or check engine light), and difficulty steering the vehicle.

2. What are the potential causes of the U0420 OBDII code in a Cadillac related to the power steering control module?

The code U0420 typically indicates a communication issue between the power steering control module and other vehicle modules, such as the engine control module or body control module. This could be caused by wiring issues, a faulty power steering control module, or a problem with the CAN bus system.

3. How can I diagnose the U0420 code in my Cadillac related to invalid data from the power steering control module?

Diagnostic steps may include checking for other related trouble codes, inspecting the wiring and connections to the power steering control module, and using a professional diagnostic scan tool to communicate with the affected modules.

4. Can I still drive my Cadillac with the U0420 code indicating invalid data from the power steering control module?

It is not recommended to drive the vehicle with an active U0420 code as it can affect the power steering function, potentially leading to unsafe driving conditions. It is best to address the issue promptly to ensure safe operation of the vehicle.

5. How can I repair the U0420 OBDII code in my Cadillac caused by invalid data from the power steering control module?

Repair options may include repairing or replacing damaged wiring, checking and reprogramming the power steering control module, and ensuring proper communication between all modules through diagnostic procedures.

6. Are there any DIY tips for addressing the U0420 code in a Cadillac related to the power steering control module?

While some basic troubleshooting steps can be taken, such as inspecting visible wiring connections and ensuring they are secure, diagnosing and repairing the U0420 code typically requires professional knowledge and equipment due to the complex nature of the vehicle's electronic systems.

7. What should I expect in terms of repair costs for fixing the U0420 OBDII code in my Cadillac with invalid data received from the power steering control module?

Repair costs can vary depending on the exact cause of the issue. Costs may include parts replacement, labor charges, and diagnostic fees. It is advisable to consult with a qualified mechanic or dealership for an accurate estimate.

8. Can resetting the vehicle's computer clear the U0420 code related to the power steering control module in a Cadillac?

Resetting the vehicle's computer may temporarily clear the code, but if the underlying issue causing the U0420 code persists, the code is likely to return. It is important to diagnose and address the root cause of the problem for a lasting solution.

9. How urgent is it to address the U0420 code indicating invalid data from the power steering control module in my Cadillac?

It is recommended to address the U0420 code promptly to prevent potential safety hazards while driving, such as loss of power steering assist. Ignoring the code could lead to further damage or issues with the vehicle's steering system.

10. Is the U0420 OBDII code related to invalid data from the power steering control module a common issue in Cadillacs?

While the U0420 code specifically related to the power steering control module may not be as common as other codes, communication errors between modules can occur in modern vehicles. Proper diagnosis and repair are key to resolving the issue effectively.