P0804 Mercedes-Benz Code - 1-4 Upshift Skip Shift Lamp Control Circuit Malfunction
Quick Answer
An ignition voltage is supplied to the Skip Shift Lamp. Common causes include Faulty Skip Shift Lamp, Skip Shift Lamp harness is open or shorted, Skip Shift Lamp 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
- P0804 Mercedes-Benz indicates 1-4 Upshift Skip Shift Lamp Control Circuit Malfunction.
- Common causes
- Common causes include Faulty Skip Shift Lamp, Skip Shift Lamp harness is open or shorted, Skip Shift Lamp 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.
Code P0804 Mercedes-Benz Description
What are the Possible Causes of the DTC P0804 Mercedes-Benz?
- Faulty Skip Shift Lamp
- Skip Shift Lamp harness is open or shorted
- Skip Shift Lamp circuit poor electrical connection
How to Fix the DTC P0804 Mercedes-Benz?
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 P0804 Mercedes-Benz 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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Frequently Asked Questions about P0804 Mercedes-Benz Code
1. What does the OBDII code P0804 mean for a Mercedes-Benz?
The P0804 code indicates a malfunction in the 1-4 Upshift Skip Shift Lamp Control Circuit, which is responsible for managing the upshift indicator light in the vehicle.
2. What are the common symptoms of the P0804 code on a Mercedes-Benz?
Common symptoms include the upshift indicator light not working properly, erratic shifting behavior, or a lack of guidance for optimal gear changes.
3. What causes the P0804 code to appear on a Mercedes-Benz?
The code can be caused by a faulty upshift lamp, damaged wiring or connectors in the control circuit, or a malfunctioning transmission control module (TCM).
4. Can I drive my Mercedes-Benz with the P0804 code?
While the vehicle may still be drivable, ignoring the code can lead to inefficient shifting, reduced fuel economy, or potential damage to the transmission.
5. How is the P0804 code diagnosed in a Mercedes-Benz?
A technician will inspect the wiring and connectors, test the upshift lamp, and use a scan tool to check the functionality of the transmission control module.
6. What repairs are needed to fix the P0804 code?
Repairs may include replacing a faulty upshift lamp, repairing or replacing damaged wiring or connectors, or reprogramming or replacing the transmission control module.
7. How much does it cost to fix the P0804 code on a Mercedes-Benz?
The cost can range from $100 to $500, depending on whether minor repairs like fixing wiring are needed or if major components such as the TCM require replacement.
8. Can a low battery cause the P0804 code?
Yes, a weak or low battery can sometimes cause circuit-related codes, including P0804, due to insufficient power supply to the control systems.
9. Can I reset the P0804 code without fixing the issue?
While you can clear the code with an OBDII scanner, it is likely to return if the underlying issue is not addressed.
10. Does the P0804 code affect fuel efficiency in a Mercedes-Benz?
Yes, if the upshift indicator is not functioning correctly, it can lead to improper gear changes, reducing fuel efficiency over time.
Discuss the causes and fixes for P0804 Mercedes-Benz OBDII Code
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