Engine-Codes.com
Engine-Codes – Hummer – P0804 Hummer

P0804 Hummer Code - Skip Shift Lamp Control Circuit

Quick Answer

The P0804 diagnostic trouble code (DTC) specifically pertains to the Skip Shift Lamp Control Circuit in Hummer vehicles. Common causes include Electrical faults in the control circuit, Damaged wiring leading to the skip shift lamp, Faulty connectors in the control circuit. 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
P0804 Hummer indicates Skip Shift Lamp Control Circuit.
Common causes
Common causes include Electrical faults in the control circuit, Damaged wiring leading to the skip shift lamp, Faulty connectors in the control circuit.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 11, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0804 Hummer Description

The P0804 diagnostic trouble code (DTC) specifically pertains to the Skip Shift Lamp Control Circuit in Hummer vehicles. This code indicates that there is an issue with the control circuit for the skip shift lamp, which is designed to illuminate when the skip shift feature is activated. The skip shift system is a fuel-saving mechanism that forces a skip from first to fourth gear under certain driving conditions to enhance fuel efficiency. When this code is triggered, it means that the control circuit for the skip shift lamp is not functioning properly, which can lead to various issues.

OBDII Code P0804 Hummer - Skip Shift Lamp Control Circuit
P0804 Hummer Code - Skip Shift Lamp Control Circuit

Common Causes of P0804 Hummer

  1. Electrical faults in the control circuit.
  2. Damaged wiring leading to the skip shift lamp.
  3. Faulty connectors in the control circuit.
  4. Malfunctioning skip shift lamp.
  5. Corrosion or loose connections in the circuit.

Symptoms of P0804 Hummer

  1. Check Engine Light is illuminated on the dashboard.
  2. Skip shift lamp does not illuminate when skip shift feature is activated.
  3. Poor fuel efficiency.
  4. Difficulty shifting gears.

How to Fix P0804 Hummer

  1. Diagnose the root cause of the issue by using a scan tool to retrieve the DTC and inspecting the control circuit for any visible damage.
  2. Repair or replace any damaged wiring or connectors in the control circuit.
  3. Test the skip shift lamp to ensure it is functioning correctly, replacing it if necessary.
  4. Clear the DTC and reset the system to see if the issue has been resolved.
  5. Test drive the vehicle to confirm that the skip shift feature is working properly and the skip shift lamp illuminates when needed.

Cost to Fix P0804 Hummer

The typical repair costs for addressing the P0804 code in a Hummer can range from $100 to $300, including parts and labor. However, it is important to note that specific diagnosis time and labor rates at auto repair shops can vary depending on factors such as location, vehicle make and model, and engine type. Auto repair shops commonly charge between $80 and $150 per hour for labor, but rates may be higher in metropolitan areas or at dealerships, while independent shops may charge less. It is recommended to inquire about local rates for a more accurate estimate of repair costs.

When is the Code Detected?

When the Powertrain Control Module (PCM) commands the control circuit to a component OFF, the voltage potential of the circuit should be high (near battery voltage). If the fault detection circuit senses a voltage other than what is expected, the fault line status changes causing theP0804 code is set.

Need more information about the P0804 Hummer code?

Need more information on how to fix the P0804 Hummer code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0804 Hummer code diagnosed by a professional: Find a repair shop in your area

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 P0804 Hummer Code

1. What are the common symptoms of OBDII code P0804 (Hummer) related to the Skip Shift Lamp Control Circuit?

The common symptoms include the skip shift lamp not illuminating properly or staying on constantly, difficulty shifting gears, and potential issues with the skip shift function.

2. What are the possible causes of OBDII code P0804 in a Hummer?

The code P0804 in a Hummer is typically caused by a faulty skip shift lamp control circuit, a defective skip shift solenoid, wiring issues, or a malfunctioning PCM (powertrain control module).

3. How can I diagnose the cause of OBDII code P0804 in my Hummer?

Diagnosing OBDII code P0804 involves checking the skip shift lamp operation, inspecting the skip shift solenoid and its wiring for any damage, and using a scan tool to analyze the PCM data for any related faults.

4. Can I still drive my Hummer with OBDII code P0804 present?

It is generally safe to drive your Hummer with the P0804 code, but it is recommended to address the issue promptly to prevent potential transmission problems and ensure proper functionality of the skip shift system.

5. How do I repair OBDII code P0804 in my Hummer?

Repairing OBDII code P0804 may involve replacing the skip shift solenoid, repairing or replacing damaged wiring, or resetting the PCM to clear the fault code. It is advisable to seek professional help if you are not familiar with automotive electrical systems.

6. Is OBDII code P0804 a serious issue in a Hummer?

While OBDII code P0804 may not pose an immediate danger, it can lead to transmission-related issues if left unresolved. It is best to address the problem promptly to avoid further complications.

7. Can a DIY enthusiast fix OBDII code P0804 in a Hummer?

If you have experience working on automotive electrical systems and access to the necessary tools, you may be able to diagnose and repair OBDII code P0804 yourself. However, if you are unsure or uncomfortable with the process, it is recommended to consult a professional mechanic.

8. How much does it cost to repair OBDII code P0804 in a Hummer?

The cost of repairing OBDII code P0804 in a Hummer can vary depending on the specific cause of the issue, the labor rates in your area, and whether you choose to replace parts yourself or have a mechanic perform the repairs. It is advisable to get a few quotes from different repair shops.

9. Can OBDII code P0804 in a Hummer trigger other fault codes?

In some cases, OBDII code P0804 may trigger additional fault codes related to the transmission or communication issues. It is essential to address all fault codes present to ensure a comprehensive repair.

10. How can I prevent OBDII code P0804 from recurring in my Hummer?

To prevent OBDII code P0804 from recurring, it is essential to perform regular maintenance on the skip shift system, inspect the wiring for any damage periodically, and address any related issues promptly to avoid further complications.

Discuss the causes and fixes for P0804 Hummer OBDII Code

Submit a New Comment

Code P0804 Hummer comments

No comments found for this page.