AutoCodes – Cadillac – P16FF Cadillac

P16FF Cadillac Code - Engine Controls Ignition Relay Request Signal Message Counter Incorrect

Quick Answer

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Common causes include Faulty Engine Controls Ignition Relay, Engine Controls Ignition Relay harness is open or shorted, Engine Controls Ignition Relay 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: P16FF Cadillac indicates Engine Controls Ignition Relay Request Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Engine Controls Ignition Relay, Engine Controls Ignition Relay harness is open or shorted, Engine Controls Ignition Relay 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 688

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 29, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P16FF Cadillac Description

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Operating information and commands are exchanged among the control modules. Each module on the serial data circuit maintains a transmit error counter and a receive error counter. The counter values increase with detected errors and decrease with error-free messages. The Diagnostic Trouble Code (DTC) will be set when the Engine Controls Ignition Relay Request Signal Message Counter Incorrect.

OBDII Code P16FF Cadillac - Engine Controls Ignition Relay Request Signal Message Counter Incorrect - AutoCodes.com — P16FF Cadillac Code - Engine Controls Ignition Relay Request Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P16FF Cadillac?

Faulty Engine Controls Ignition Relay
Engine Controls Ignition Relay harness is open or shorted
Engine Controls Ignition Relay circuit poor electrical connection

How to Fix the DTC P16FF 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 P16FF 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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Need more information on how to fix the P16FF Cadillac code? Get Access to Factory Service Manuals

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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 P16FF Cadillac Code

1. What does the OBDII code P16FF mean on a Cadillac?

P16FF indicates that the Engine Control Module (ECM) has detected an issue with the ignition relay request signal message counter, suggesting a communication or data error.

2. What are the common symptoms of code P16FF?

Symptoms may include difficulty starting the engine, stalling, reduced engine performance, or the illumination of the Check Engine Light.

3. What causes the P16FF code to appear on a Cadillac?

Common causes include a faulty ignition relay, damaged wiring or connectors in the ignition circuit, or an issue with the Engine Control Module (ECM).

4. Can a loose electrical connection cause code P16FF?

Yes, loose or corroded electrical connections in the ignition relay circuit can disrupt communication and trigger the P16FF code.

5. How is the P16FF code diagnosed?

A mechanic will inspect the ignition relay, wiring, and connectors, and use a diagnostic scanner to check for additional codes or perform communication tests with the ECM.

6. Can I drive my Cadillac with the P16FF code active?

Itâ€™s not recommended to drive with this code active, as it may lead to stalling or other engine performance issues that can affect safety.

7. How do you fix the P16FF code on a Cadillac?

Repairs may involve replacing the ignition relay, repairing or replacing damaged wiring, or reprogramming or replacing the ECM if necessary.

8. Is the P16FF code related to a failed ignition relay?

Yes, a failed ignition relay is one of the most common causes of the P16FF code.

9. Can a software update fix the P16FF code?

In some cases, a software update or ECM reprogramming performed by a dealership may resolve the issue if itâ€™s due to a communication error.

10. How much does it cost to repair the P16FF code on a Cadillac?

The cost varies depending on the root cause but typically ranges from $100 to $400 for parts and labor, with ECM replacement or programming being more expensive.