Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the light that tells you when to shift gears. It's like when a video game tells you to press a button, but the button doesn't light up to show you when to press it.
The P0804 code is triggered when there is a malfunction in the circuit that controls the upshift or skip shift lamp, which is used to indicate to the driver the optimal time to shift gears.
The P0804 code indicates a problem with the electrical circuit responsible for the upshift or skip shift lamp. This lamp is part of the vehicle's transmission management system, which helps optimize fuel efficiency and performance by signaling the driver when to shift gears. A fault in this circuit can lead to improper gear shifting indications.
• Upshift/skip shift lamp not working
• Inconsistent gear shifting indications
• Possible decrease in fuel efficiency
• Faulty upshift/skip shift lamp
• Wiring issues in the lamp circuit
• Malfunctioning transmission control module (TCM)
Upshift: Changing to a higher gear in a vehicle.
Skip Shift: A system that forces the driver to skip certain gears to improve fuel efficiency.
• Check the upshift/skip shift lamp for functionality.
• Inspect the wiring and connections in the lamp circuit.
• Test the transmission control module for faults.
• Replace the upshift/skip shift lamp if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if needed.
• Multimeter
• OBD-II scanner
• Screwdriver set
$100 - $300
Moderate
• Chevrolet Camaro
• Dodge Challenger
• Ford Mustang
• Regularly inspect electrical connections.
• Ensure proper maintenance of the transmission system.
• Avoid excessive force when shifting gears.
Sensor Issue
• Pay attention to any changes in gear shifting behavior.
• Consult a professional mechanic if the issue persists.
Check with your vehicle manufacturer for warranty coverage on electrical components.
The P0804 code has been associated with manual transmission vehicles that use a shift indicator system to enhance fuel efficiency.
Low – This code does not typically affect drivability but should be addressed to ensure optimal performance.
Driving with a malfunctioning shift indicator may not be illegal, but it can lead to inefficient driving habits.
• Vehicle in a safe, stationary position
• Engine running and transmission in neutral
The upshift/skip shift lamp is typically located on the vehicle's dashboard, near the instrument cluster.
Q: Can I drive with the P0804 code?
A: Yes, but it's best to get it checked soon to ensure your vehicle is running efficiently.
Q: Will fixing the P0804 code improve my fuel efficiency?
A: Yes, resolving this issue can help you shift gears at the optimal time, which may improve fuel efficiency.
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