AutoCodes – Cadillac – P15C6 Cadillac

P15C6 Cadillac Code - Electric A/C Compressor Speed Request Signal Message Counter Incorrect

Quick Answer

The hybrid powertrain control module 2 receives serial data messages from the A/C compressor. Common causes include Faulty Electric A/C Compressor, Electric A/C Compressor harness is open or shorted, Electric A/C Compressor 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: P15C6 Cadillac indicates Electric A/C Compressor Speed Request Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Electric A/C Compressor, Electric A/C Compressor harness is open or shorted, Electric A/C Compressor 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 765

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 Jan 03, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P15C6 Cadillac Description

The hybrid powertrain control module 2 receives serial data messages from the A/C compressor. If the message counter from the A/C compressor is not incrementing based on the currently commanded state, the hybrid powertrain control module 2 sets the DTC.

OBDII Code P15C6 Cadillac - Electric A/C Compressor Speed Request Signal Message Counter Incorrect - AutoCodes.com — P15C6 Cadillac Code - Electric A/C Compressor Speed Request Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P15C6 Cadillac?

Faulty Electric A/C Compressor
Electric A/C Compressor harness is open or shorted
Electric A/C Compressor circuit poor electrical connection

How to Fix the DTC P15C6 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 P15C6 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 P15C6 Cadillac Code

1. What does the OBDII code P15C6 mean on a Cadillac?

Code P15C6 indicates an issue with the Electric A/C Compressor Speed Request Signal Message Counter, suggesting a communication problem between the HVAC control module and the electric A/C compressor.

2. What are the common symptoms of code P15C6?

Common symptoms include reduced or no air conditioning performance, inconsistent cabin cooling, and the A/C system failing to operate as intended.

3. What causes the P15C6 code to appear?

This code is often caused by issues such as a faulty electric A/C compressor, wiring problems, a malfunctioning HVAC control module, or corrupted communication signals.

4. Can a bad A/C compressor cause the P15C6 code?

Yes, a malfunctioning electric A/C compressor or its internal electronics can trigger this code.

5. How do I diagnose the P15C6 code?

Diagnosis involves checking the wiring and connectors between the HVAC control module and the A/C compressor, scanning for additional codes, and testing the communication signals with a diagnostic tool.

6. Is it safe to drive with the P15C6 code?

While you can generally drive with this code, you may experience discomfort due to the A/C not functioning properly. Prolonged operation without repair may lead to further system issues.

7. Can clearing the P15C6 code fix the problem?

Clearing the code may temporarily reset the system, but if the underlying issue isnâ€™t resolved, the code will likely return.

8. How much does it cost to fix the P15C6 code?

Repair costs vary depending on the root cause. Replacing a damaged compressor can cost $1,000â€“$2,500, while simpler fixes like repairing wiring may cost significantly less.

9. Can a software update resolve the P15C6 code?

In some cases, a software update for the HVAC control module can fix communication issues causing the code, but this depends on the specific Cadillac model and year.

10. Should I take my Cadillac to a professional for the P15C6 code?

Yes, due to the complexity of the A/C system and the need for specialized diagnostic tools, itâ€™s recommended to have a professional address the issue.