Engine-CodesCadillac – P135B Cadillac

P135B Cadillac Code - Ignition Coil Supply Voltage Circuit Bank 2

Quick Answer

The P135B diagnostic trouble code (DTC) for Cadillac vehicles refers to a problem with the Ignition Coil Supply Voltage Circuit on Bank 2. Common causes include Faulty wiring or connections in the ignition coil supply circuit, Malfunctioning ignition coil on Bank 2, Issue with the engine control module (ECM). 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
P135B Cadillac indicates Ignition Coil Supply Voltage Circuit Bank 2.
Common causes
Common causes include Faulty wiring or connections in the ignition coil supply circuit, Malfunctioning ignition coil on Bank 2, Issue with the engine control module (ECM).
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.
Table of contents Created and updated by William Orellana on Sep 07, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P135B Cadillac Description

The P135B diagnostic trouble code (DTC) for Cadillac vehicles refers to a problem with the Ignition Coil Supply Voltage Circuit on Bank 2. This code indicates that there is an issue with the electrical circuit that supplies power to the ignition coil on the second bank of cylinders in the engine. The ignition coil plays a crucial role in the ignition system by converting the low voltage from the battery into the high voltage needed to create a spark for the spark plugs.

OBDII Code P135B Cadillac - Ignition Coil Supply Voltage Circuit Bank 2
P135B Cadillac Code - Ignition Coil Supply Voltage Circuit Bank 2

Common Causes of P135B Cadillac

  1. Faulty wiring or connections in the ignition coil supply circuit
  2. Malfunctioning ignition coil on Bank 2
  3. Issue with the engine control module (ECM)
  4. Electrical system problems affecting power supply to the ignition coil
  5. Water or moisture intrusion into the ignition coil circuit

Symptoms of P135B Cadillac

  1. Engine misfires
  2. Rough idling
  3. Decreased fuel efficiency
  4. Hesitation during acceleration
  5. Stalling

How to Fix P135B Cadillac

  1. Begin by conducting a thorough visual inspection of the ignition coil supply circuit on Bank 2, checking for any loose connections, damaged wiring, or signs of corrosion.
  2. Test the ignition coil on Bank 2 using a multimeter to determine if it is functioning properly. Replace the ignition coil if necessary.
  3. Check the engine control module (ECM) for any fault codes related to the ignition coil supply voltage circuit. If necessary, reprogram or replace the ECM.
  4. Inspect the vehicle's electrical system to ensure a consistent power supply to the ignition coil. Address any issues with the battery, alternator, or wiring as needed.
  5. Clear the diagnostic trouble code (DTC) from the vehicle's computer using an OBD-II scanner and test drive the vehicle to confirm that the issue has been resolved.

Cost to Fix P135B Cadillac

The typical repair costs for addressing the P135B DTC on a Cadillac vehicle can range from $150 to $400, depending on the extent of the damage and the specific components that need to be replaced. This estimate includes the cost of parts such as the ignition coil, wiring harness, or ECM, as well as labor costs for diagnosis and repair. It's important to note that labor rates at auto repair shops can vary widely, so it's advisable to check with local shops for a more accurate estimate based on your location and vehicle model.

Need more information about the P135B Cadillac code?

Need more information on how to fix the P135B Cadillac code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P135B Cadillac code diagnosed by a professional: Find a repair shop in your area

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 P135B Cadillac Code

What does the OBDII code P135B mean on a Cadillac?

The P135B code indicates an issue with the ignition coil supply voltage circuit for Bank 2, meaning the power supply to one or more ignition coils is disrupted.

What are the common symptoms of the P135B code?

Symptoms include engine misfires, rough idling, reduced power, poor fuel economy, and the check engine light being illuminated.

What causes the P135B code to appear?

Causes can include a faulty ignition coil, damaged wiring or connectors in the ignition coil circuit, a blown fuse, or issues with the powertrain control module (PCM).

How do you diagnose the P135B code on a Cadillac?

Diagnosis involves inspecting the ignition coil wiring and connectors, testing the ignition coil for proper function, checking for blown fuses, and verifying the PCM is functioning correctly.

Can a faulty ignition coil trigger the P135B code?

Yes, a malfunctioning ignition coil on Bank 2 can disrupt the supply voltage and trigger the P135B code.

Is it safe to drive with the P135B code active?

It’s not recommended to drive with this code active, as it can lead to engine misfires, reduced performance, and potential damage to other engine components.

How can I fix the P135B code on my Cadillac?

Repairs may involve replacing a faulty ignition coil, repairing or replacing damaged wiring, inspecting and replacing a blown fuse, or reprogramming or replacing the PCM if necessary.

How much does it cost to repair the P135B code?

The cost varies depending on the root cause, with ignition coil replacement typically costing $150–$300, while wiring repairs or PCM replacement may cost more.

Can a weak battery cause the P135B code?

A weak or failing battery can potentially cause voltage irregularities that affect the ignition coil circuit, leading to the P135B code.

What tools are needed to troubleshoot the P135B code?

Common tools include an OBDII scanner, a digital multimeter for testing voltage, and basic hand tools for inspecting and repairing wiring or components.

Discuss the causes and fixes for P135B Cadillac OBDII Code

Code P135B Cadillac comments

No comments found for this page.