P0670 Trouble Code: Meaning, Symptoms, Causes & Fixes

If you’re encountering the P0670 trouble code on your car’s diagnostic system, you’re likely looking for clarity and solutions.

This guide will walk you through its meaning, symptoms, causes, and how you can fix it. You’re likely reading this because the P0670 code has popped up and you’re eager to understand what it entails and how to address it effectively.

In my years as a mechanic, I’ve tackled the P0670 issue in numerous diesel engines. Trust me, it’s fixable.

In this article, we’ll delve into how this code can affect your vehicle’s performance and provide step-by-step troubleshooting advice to get your ride running smoothly again.

Ready to roll up your sleeves and get into the nitty-gritty? Let’s jump in.

Related:P064C Trouble Code: Meaning, Symptoms, Causes & FixesP0684 Trouble Code: Meaning, Symptoms, Causes & FixesP0683 Trouble Code: Meaning, Symptoms, Causes & Fixes

What Does P0670 Trouble Code Mean?

The P0670 trouble code is a specific diagnostic alert related to the glow plug control module in diesel engines.

This module is crucial as it manages the electric current that heats the glow plugs during engine start-up.

The glow plugs are essential for igniting the diesel fuel in the combustion chamber when the engine is cold.

When your vehicle’s diagnostic system registers the P0670 code, it indicates that there is a communication problem between the glow plug control module and the engine control module (ECM).

This could mean the control module isn’t operating correctly, or there might be a fault in the communication pathways, such as the wiring or connectors.

This malfunction can manifest in various ways. Primarily, it affects the vehicle’s ability to start efficiently in cold conditions.

Since the glow plugs are integral to heating the engine to the proper temperature for ignition, any issue with the control module might result in your engine struggling to start or performing poorly during the warm-up phase.

In some cases, the engine might not start at all if the outside temperature is particularly low and the glow plugs fail to heat up adequately.

The presence of this code also triggers the check engine light on your dashboard, which is your first indicator that something is amiss.

Ignoring this warning can lead to further complications, including potential damage to the engine if the problem persists over time.

It’s crucial to address this issue promptly to ensure optimal engine performance, especially in cooler climates where diesel engines are more common.

In summary, the P0670 code is a signal that there’s a fault in the glow plug control module circuit, impacting your engine’s start and performance under cold conditions.

Addressing this quickly will help maintain your engine’s health and reliability.

P0670 Trouble Code Symptom

Here are the key symptoms that might indicate the P0670 trouble code is present in your vehicle:

• Difficulty starting the engine, especially in cold weather
• The engine takes longer than usual to start
• Poor engine performance during the initial minutes after starting
• The check engine light is illuminated on the dashboard
• Increased fuel consumption
• Occasional misfires during startup or operation in cold conditions

P0670 Trouble Code Causes

The P0670 trouble code can be triggered by several issues within the vehicle’s glow plug system:

• Faulty glow plug control module
• Damaged or corroded wiring and connectors in the glow plug circuit
• Faulty glow plugs
• Issues with the engine control module (ECM)
• Poor electrical connections affecting the glow plug system

How To Fix A P0670 Trouble Code

Fixing a P0670 trouble code involves a series of diagnostic checks and repairs. Here’s a step-by-step guide on how to diagnose and address this issue:

1. Scan and Document

Start by using an OBD-II scanner to confirm the presence of the P0670 trouble code. Document any other codes that may also appear as they can provide clues about related issues.

2. Visual Inspection

Inspect the glow plug system. Check for visible signs of damage or wear on the glow plug control module, wiring, and connectors. Look for burnt, damaged, or corroded components.

3. Check the Glow Plugs

Test each glow plug individually. A multimeter can be used to measure the resistance of each plug. Replace any that do not meet the manufacturer’s specifications.

4. Examine the Control Module

Evaluate the glow plug control module’s operation. Check its connections and ground, ensuring they are secure and free from corrosion. Consider using a diagnostic tool to test the module’s output.

5. Wiring Harness Check

Thoroughly inspect the wiring harness for shorts, breaks, or other damages. Pay special attention to connectors and junction points. Repair or replace any defective sections.

6. Replace Faulty Parts

If specific faults are found in the glow plug control module, glow plugs, or wiring, replace these parts with OEM (Original Equipment Manufacturer) or equivalent components.

7. Clear the Codes and Test Drive

Once repairs are made, clear all diagnostic trouble codes with the OBD-II scanner. Then, perform a test drive to ensure that the issue is resolved and the P0670 code does not reappear.

8. Follow-up Scan

After a test drive, use the scanner again to ensure no codes are present. This confirms the fix was successful.

Addressing the P0670 can be straightforward if systematic checks are conducted. For those uncomfortable with performing these tasks, seeking assistance from a professional mechanic is advised.

Conclusion

Now that you’re up to speed on the P0670 trouble code, you know what it signifies and the steps to fix it.

Have you ever encountered this issue with your vehicle? What was your experience?

Feel free to drop a comment below! Did these tips help, or do you have other tricks?