2004 Mercedes-Benz C-Class Problems: 1 Known Issue
2004 model year · 2,500+ owner reports · Updated October 2026
According to Au7o's analysis of 2,500+ owner reports, the 2004 Mercedes-Benz C-Class has 1 documented issue, with 1 rated critical. The most serious is SAM Module Failure ($600-$1,800 repair). The most commonly reported issue is SAM Module Failure with 2,500 owner reports. Across all issues with published estimates, repair costs range from $600 to $1,800. DIY maintenance guides at au7o.io.
2004 · All trims · All engines
Choose the year and equipment for your written issues and visual request.
No email neededHow interest is saved
Interest applies to the selected vehicle and configuration; it is not a reservation. Voting stores a first-party identifier for up to 180 days to prevent repeat votes. No account or email is needed. Clearing cookies or using another device may count separately. Privacy
Visual coming soon
Your interest helps us choose what to build next.
Visual Known Issues · Coming soon
$4.99/month plus taxes at launch · No payment today
All 1 Known Issue
Join 600+ people using Au7o to better understand their vehicles.
Don't see your problem? Describe your symptoms to get a diagnosis, or get a full repair guide.
Other Mercedes-Benz Models
Frequently Asked Questions
What are the most common Mercedes-Benz C-Class problems?
According to Au7o's analysis of 2,500+ owner reports, the 2004 Mercedes-Benz C-Class has 1 documented issue. The documented issue is: SAM Module Failure. Of these, 1 is rated critical and should be addressed promptly.
Is the Mercedes-Benz C-Class reliable?
The 2004 Mercedes-Benz C-Class has 1 known issue documented across 2,500+ owner reports. 1 issue is rated critical: SAM Module Failure. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Mercedes-Benz C-Class problems?
Repair costs for known Mercedes-Benz C-Class issues range from $600 to $1,800, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, SAM Module Failure, typically costs $600-$1,800 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2001-2007 Mercedes-Benz C-Class SAM Module Failure?
The Signal Acquisition Module (SAM) — essentially the fuse box and body control module — fails due to water intrusion or internal solder joint cracking. Causes erratic electrical behavior including lights, wipers, and windows malfunctioning. Repairs typically run $600-$1,800. Severity: high.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.