2024–2026 GM Truck Owners

Fix Your “Service Trailer Brake System” Warning

If your 2024–2026 Silverado, Sierra, Tahoe, Yukon, or Denali has disabled your trailer brakes, HydraStar has the fix. Our 381-7074 / 7075 modules are the only on-market solution — and GM dealerships are sending customers straight to us.

✓ Plug & Play Install✓ Ships Same Day✓ Made in USA

Shop the Fix →Which Part Do I Need?

2024 GM truck dashboard displaying Service Trailer Brake System warning message

⚠ This Warning?

Affected Vehicles

Which Trucks Have This Problem?

2024–2026 Chevrolet Silverado

2024–2026 GMC Sierra

2024–2026 Chevrolet Tahoe / Suburban

2024–2026 GMC Yukon / Denali

GM’s new body-style trucks use a different brake controller signal that disables electric-over-hydraulic trailer brakes. You’ll see a “Service Trailer Brake System” warning on your dash and your trailer brakes stop working entirely. This is not a trailer problem — it’s a vehicle compatibility issue, and the HydraStar CAM is the only fix.

The Solution

Which Part Do I Need?

Pick based on the brakes on your trailer. Not sure? Call (812) 655-4544 or use the chat — we’ll figure it out with you in under a minute.

Most Common

Hydrastar 381-7074 GM Controller Adapter Module for Electric Over Hydraulic

Part # 381-7074

For Electric-Over-Hydraulic (EOH) Brakes

If your trailer uses a HydraStar (or other-brand) EOH actuator, this is the fix. Plug-and-play install in 5–10 minutes.

$76.00

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Part # 381-7075

For Electric Drum Brakes

If your trailer uses standard electric drum brakes (no hydraulic actuator), this is the fix. Inline plug-and-play, no splicing.

$69.00$75.00

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2024 GM truck dashboard showing Service Trailer Brake System warning message

If You See This Warning

The “Service Trailer Brake System” message on a 2024+ Silverado, Sierra, Tahoe, Suburban, Yukon, or Denali means GM’s controller has disabled your trailer brakes. It’s not a trailer fault — it’s a controller compatibility issue, and the 381-7074 / 7075 modules above are the only on-market fix.

Driving a 2007–2016 Chevy or 2007–2008 Ford instead? You need our 381-7073 CAM — that’s a different fix for an older issue.

Common Questions

Before You Buy

Will this fix my “Service Trailer Brake System” warning?+

Yes. The CAM adapts the GM controller signal to work with your EOH actuator. Once installed, the warning clears and your trailer brakes function normally.

Is it hard to install?+

No. The CAM is a plug-and-play inline module. It installs between your vehicle’s 7-way connector and the trailer plug. No cutting wires, no splicing. Most installs take 5–10 minutes.

My dealer says I need this — is that right?+

Yes. GM dealerships across the country are referring customers directly to HydraStar for this fix. We’re the only manufacturer that makes a solution for this issue. There is no GM factory fix available.

Does this work with non-HydraStar actuators?+

The 381-7074 CAM works with any electric-over-hydraulic actuator (HydraStar, Tie Down, Kodiak, etc.). The 381-7075 works with standard electric drum brake setups.

What if I have a different year GM truck?+

Pre-2024 GM trucks do not have this issue. If you have a 2024 or newer truck and are experiencing the problem, the CAM is your fix. Call us at (812) 655-4544 if you’re unsure.