AutoCodes – GMC – C1278 GMC

C1278 GMC Code - TCS Temporarily Inhibited By PCM

Quick Answer

The Powertrain Control Module (PCM) monitors various parameters. Common causes include Faulty Electronic Brake Control Module (EBCM), Faulty Powertrain Control Module (PCM). 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: C1278 GMC indicates TCS Temporarily Inhibited By PCM.
Common causes: Common causes include Faulty Electronic Brake Control Module (EBCM), Faulty Powertrain Control Module (PCM).
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 1,157

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 Sep 02, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C1278 GMC Description

The Powertrain Control Module (PCM) monitors various parameters. The PCM sets the OBDII code and will not allow traction control operation if any parameter falls outside a specified range.

OBDII Code C1278 GMC - TCS Temporarily Inhibited By PCM - AutoCodes.com — C1278 GMC Code - TCS Temporarily Inhibited By PCM

What does this mean?

What are the Possible Causes of the DTC C1278 GMC?

Faulty Electronic Brake Control Module (EBCM)
Faulty Powertrain Control Module (PCM)

How to Fix the DTC C1278 GMC?

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 C1278 GMC 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 C1278 GMC Code

1. What are the common symptoms of OBDII code C1278 GMC indicating TCS temporarily inhibited by PCM?

The common symptoms include the traction control system (TCS) light being illuminated on the dashboard, loss of traction control functionality, and potential issues with the vehicle's stability control system.

2. What does it mean when the TCS is temporarily inhibited by the PCM in a GMC vehicle?

When the TCS is temporarily inhibited by the powertrain control module (PCM), it usually indicates a fault or issue with the traction control system that needs to be addressed to ensure proper vehicle safety and performance.

3. What are the possible causes of OBDII code C1278 GMC related to TCS inhibition by the PCM?

Possible causes include faulty wheel speed sensors, damaged wiring or connectors in the TCS system, issues with the ABS modulator, or a malfunctioning PCM.

4. How can I diagnose the issue causing OBDII code C1278 GMC on my GMC vehicle?

Diagnosis typically involves using a diagnostic scanner to retrieve the trouble codes, conducting a visual inspection of the TCS components, and testing the wheel speed sensors and related wiring for faults.

5. Can driving with OBDII code C1278 GMC posing TCS inhibition be dangerous?

Driving with the TCS temporarily inhibited can impact the vehicle's stability and traction control, potentially leading to reduced handling and safety on slippery or uneven road surfaces. It is recommended to address the issue promptly.

6. What are the recommended repair tips for resolving OBDII code C1278 GMC related to TCS inhibition?

Repair tips may include replacing faulty wheel speed sensors, repairing damaged wiring, ensuring proper connection of TCS components, and performing a PCM reset or reprogramming if necessary.

7. Is it possible to reset OBDII code C1278 GMC indicating TCS inhibition without fixing the underlying issue?

While clearing the trouble code may temporarily turn off the warning light, it is crucial to address the root cause of the problem to ensure the TCS functions correctly and maintain vehicle safety.

8. Can a DIY enthusiast fix OBDII code C1278 GMC associated with TCS temporarily inhibited by PCM?

Depending on the underlying cause, DIY enthusiasts with automotive repair experience may be able to address the issue by following repair guides, utilizing proper tools, and conducting thorough diagnostic procedures.

9. How much does it typically cost to repair OBDII code C1278 GMC related to TCS inhibition in a GMC vehicle?

The cost of repair can vary based on the specific issue causing the trouble code, the labor rates of the repair shop, and the cost of replacement parts. It is recommended to obtain estimates from reputable mechanics.

10. Are there any recalls or technical service bulletins related to OBDII code C1278 GMC concerning TCS inhibition by the PCM?

It is advisable to check with authorized GMC dealerships or visit the manufacturer's website to inquire about any recalls or technical service bulletins related to OBDII code C1278 GMC and TCS issues in specific vehicle models.