AutoCodes – GMC – P135A 2018 GMC Sierra

P135A 2018 GMC Sierra Code - Ignition Coil Supply Voltage Circuit Bank 1

Quick Answer

The ignition system uses an individual ignition coil for each cylinder. Common causes include Blown Ignition Coil Fuse, Ignition Coil Fuse harness is open or shorted, Ignition Coil Fuse 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: P135A 2018 GMC Sierra indicates Ignition Coil Supply Voltage Circuit Bank 1.
Common causes: Common causes include Blown Ignition Coil Fuse, Ignition Coil Fuse harness is open or shorted, Ignition Coil Fuse 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 491

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 Aug 13, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P135A 2018 GMC Sierra Description

The ignition system uses an individual ignition coil for each cylinder. The Engine Control Module (ECM) monitors the ignition voltage from the fuse to the individual coils. The Diagnostic Trouble Code (DTC) will be set if the ECM detects less than 2.5 V on the ignition coil supply voltage circuit.

OBDII Code P135A 2018 GMC Sierra - Ignition Coil Supply Voltage Circuit Bank 1 - AutoCodes.com — P135A 2018 GMC Sierra Code - Ignition Coil Supply Voltage Circuit Bank 1

What does this mean?

What are the Possible Causes of the DTC P135A 2018 GMC Sierra?

Blown Ignition Coil Fuse
Ignition Coil Fuse harness is open or shorted
Ignition Coil Fuse circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P135A 2018 GMC Sierra?

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 P135A 2018 GMC Sierra 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 P135A 2018 GMC Sierra code?

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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 P135A 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P135A in a 2018 GMC Sierra related to the Ignition Coil Supply Voltage Circuit Bank 1?

- Common symptoms include engine misfires, rough idling, loss of power, and illuminated check engine light.

2. What are the possible causes of OBDII code P135A in a 2018 GMC Sierra?

- Possible causes may include a faulty ignition coil, damaged wiring or connectors in the ignition coil circuit, or issues with the power supply to the ignition coil.

3. How can I diagnose the Ignition Coil Supply Voltage Circuit Bank 1 issue causing OBDII code P135A in my 2018 GMC Sierra?

- You can use a multimeter to test the voltage at the ignition coil, inspect the wiring and connectors for damage, and perform a visual inspection of the ignition coil itself.

4. Can a DIY enthusiast repair OBDII code P135A related to the Ignition Coil Supply Voltage Circuit Bank 1 in a 2018 GMC Sierra?

- While some basic troubleshooting can be done by a DIY enthusiast, repairing this issue may require advanced diagnostic tools and expertise. It's recommended to consult a professional mechanic for accurate diagnosis and repair.

5. Are there any safety precautions to consider when dealing with OBDII code P135A in a 2018 GMC Sierra?

- It's important to disconnect the vehicle's battery before working on any electrical components to prevent accidents or damage. Always follow proper safety procedures when handling ignition system components.

6. How does the Ignition Coil Supply Voltage Circuit Bank 1 affect the performance of a 2018 GMC Sierra?

- The Ignition Coil Supply Voltage Circuit Bank 1 is crucial for proper ignition system function. If this circuit has issues, it can lead to misfires, decreased engine performance, and potential damage to other engine components.

7. Can a bad spark plug cause OBDII code P135A in a 2018 GMC Sierra?

- While a bad spark plug can contribute to ignition issues, OBDII code P135A specifically relates to the supply voltage circuit for the ignition coil in Bank 1. It's important to focus on diagnosing and repairing the ignition coil circuit first.

8. How can regular maintenance help prevent OBDII code P135A issues in a 2018 GMC Sierra?

- Regularly checking and replacing spark plugs, inspecting ignition system components, and maintaining proper engine health can help prevent issues that may trigger OBDII code P135A related to the Ignition Coil Supply Voltage Circuit Bank 1.

9. Is it safe to continue driving a 2018 GMC Sierra with OBDII code P135A related to the Ignition Coil Supply Voltage Circuit Bank 1?

- It's not recommended to drive the vehicle with this code present, as it can lead to further engine damage and performance issues. It's best to address the underlying problem promptly to avoid more significant problems down the road.