AutoCodes – GMC – P1804 GMC

P1804 GMC Code - Ground Control Relay

Quick Answer

P1804 GMC indicates Ground Control Relay. Common causes include Faulty Ground Control Relay, Ground Control Relay harness is open or shorted, Ground Control 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: P1804 GMC indicates Ground Control Relay.
Common causes: Common causes include Faulty Ground Control Relay, Ground Control Relay harness is open or shorted, Ground Control 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 1,770

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 20, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1804 GMC Description

OBDII Code P1804 GMC - Ground Control Relay - AutoCodes.com — P1804 GMC Code - Ground Control Relay

What does this mean?

What are the Possible Causes of the DTC P1804 GMC?

Faulty Ground Control Relay
Ground Control Relay harness is open or shorted
Ground Control Relay circuit poor electrical connection

How to Fix the DTC P1804 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 P1804 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.

Need more information about the P1804 GMC code?

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Need Help with the Code?

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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 P1804 GMC Code

1. What are the common symptoms of OBDII code P1804 GMC (Ground Control Relay)?

The common symptoms of code P1804 GMC include difficulty starting the vehicle, engine stalling, and issues with the transmission shifting properly.

2. What can cause OBDII code P1804 GMC to trigger?

Code P1804 GMC is typically triggered by a faulty ground control relay, wiring issues related to the relay circuit, or a problem with the transmission control module.

3. How can I diagnose the cause of OBDII code P1804 GMC?

Diagnosing code P1804 GMC involves checking the ground control relay for continuity, inspecting the wiring for any damage or loose connections, and testing the transmission control module for proper functioning.

4. What should I do if I encounter OBDII code P1804 GMC?

If you encounter code P1804 GMC, it is recommended to address the issue promptly to prevent further damage to the transmission system. Consult a professional mechanic for a thorough diagnosis and repair.

5. Can I drive my vehicle with OBDII code P1804 GMC?

It is not advisable to drive your vehicle with code P1804 GMC present, as it can lead to transmission issues and potential safety hazards. It is best to have the problem resolved before continuing to drive the vehicle.

6. Is repairing OBDII code P1804 GMC a DIY task?

Repairing code P1804 GMC may require advanced knowledge of automotive electrical systems and transmission components. It is recommended to seek the assistance of a qualified mechanic for proper diagnosis and repair.

7. What are some tips for preventing OBDII code P1804 GMC from recurring?

To prevent code P1804 GMC from recurring, ensure proper maintenance of the transmission system, address any electrical issues promptly, and avoid overloading the vehicle beyond its capacity.

8. Can resetting the OBDII codes clear P1804 GMC?

Resetting the OBDII codes may temporarily clear code P1804 GMC, but if the underlying issue is not addressed, the code is likely to reappear. It is important to diagnose and repair the root cause of the problem.

9. How much does it cost to repair OBDII code P1804 GMC?

The cost of repairing code P1804 GMC can vary depending on the extent of the issue, the parts needed for repair, and the labor rates of the repair shop. It is advisable to obtain quotes from different mechanics for an accurate estimate.

10. Is OBDII code P1804 GMC a serious issue?

Code P1804 GMC should be taken seriously as it can lead to transmission problems and affect the overall drivability of the vehicle. Prompt diagnosis and repair are recommended to avoid potential complications.