AutoCodes – Generic – P1E42

P1E42 Code - Electric Servo Brake System Fail-Safe Relay Stuck Off

Quick Answer

The Engine Control Module (ECM) monitors the Electric Servo Brake. Common causes include Faulty Electric Servo Brake, Electric Servo Brake harness is open or shorted, Electric Servo Brake 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: P1E42 indicates Electric Servo Brake System Fail-Safe Relay Stuck Off.
Common causes: Common causes include Faulty Electric Servo Brake, Electric Servo Brake harness is open or shorted, Electric Servo Brake 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 1,956

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 24, 2020

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 P1E42 Description

The Engine Control Module (ECM) monitors the Electric Servo Brake. The ECM sets the OBDII code when the Electric Servo Brake is not to factory specifications.

OBDII Code P1E42 - Electric Servo Brake System Fail-Safe Relay Stuck Off - AutoCodes.com — P1E42 Code - Electric Servo Brake System Fail-Safe Relay Stuck Off

What does this mean?

What are the Possible Causes of the DTC P1E42?

Faulty Electric Servo Brake
Electric Servo Brake harness is open or shorted
Electric Servo Brake circuit poor electrical connection

How to Fix the DTC P1E42?

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 P1E42 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 P1E42 code?

Need more information on how to fix the P1E42 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1E42 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1E42 Acura — Electric Servo Brake System Fail-Safe Relay Stuck Off
P1E42 Honda — Electric Servo Brake System Fail-Safe Relay Stuck Off

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 P1E42 Code

1. What does the OBDII code P1E42 mean?

The P1E42 code indicates that the Electric Servo Brake System's fail-safe relay is stuck in the "off" position, preventing proper brake operation.

2. What are the symptoms of a P1E42 code?

Symptoms may include a brake warning light, reduced braking performance, ABS or traction control system malfunctions, and potentially longer stopping distances.

3. What causes the P1E42 code?

Common causes include a faulty fail-safe relay, damaged wiring or connectors in the brake system, or issues with the Electric Servo Brake System control module.

4. Is it safe to drive with a P1E42 code?

No, driving with a P1E42 code can compromise braking performance, increasing the risk of an accident. Repairs should be addressed immediately.

5. How can I diagnose the P1E42 code?

Use an OBDII scanner to confirm the code, then inspect the fail-safe relay, wiring, and connectors for damage or corrosion. Check the control module for faults.

6. How is the P1E42 code repaired?

Repairs may include replacing the fail-safe relay, repairing or replacing damaged wiring, cleaning corroded connections, or reprogramming the brake system control module.

7. Can a weak battery cause the P1E42 code?

Yes, a weak or failing battery can cause electrical issues that may trigger the P1E42 code. Ensure the battery is fully charged and in good condition.

8. How much does it cost to fix the P1E42 code?

Repair costs vary but can range from $100 to $500 or more, depending on whether the relay, wiring, or control module requires replacement.

9. Can the P1E42 code cause other OBDII codes to appear?

Yes, the P1E42 code may be accompanied by other brake or ABS-related codes if the Electric Servo Brake System is malfunctioning.

10. Do I need a professional mechanic to fix the P1E42 code?

While basic inspections can be done at home, diagnosing and repairing the fail-safe relay or control module often requires specialized tools and expertise, so professional assistance is recommended.