Tech Tip: BMW no start, bad CAS module

Sept. 8, 2017

Vehicle: 2008 BMW 335xi, AWD (E90), L6-3.0L Turbo (N54), Automatic Transmission

Mileage: 118,669

Problem: When trying to start the engine, the starter momentarily engaged then stopped.

Details: The tech found that, while attempting to crank/start the engine, the starter solenoid was only powered for a split second. He connected a scan tool and retrieved an A0C1 (Output Terminal 50) diagnostic trouble code.

The ALLDATA Tech-Assist consultant suggested he open the Car Access System (CAS) module to inspect for signs of burned spots on the circuit board.

Confirmed Repair: When the tech opened the CAS module, he found several burned circuits. He replaced the CAS module. After the repair, the engine started and ran normally.

Information provided by: ALLDATA

Sponsored Recommendations

AIRCAT Solutions - Small Ratchets With Enormous Power

Experience the power of AIRCAT's diverse ratchet selection. Each designed with a unique transmission gear for faster torque buildup and unbeatable performance. Their compact sizes...

Unmatched Power and Comfort: AIRCAT Grinders for Every Workspace

AIRCAT grinders deliver powerful performance with high RPM and efficient, quiet operation. Designed for comfort and control, they feature ergonomic handles, extended reach, and...

What Are the Advantages of Air Tools Over Cordless Tools?

Discover the advantages of air tools over cordless tools.

AIRCAT Tool Reviews: The Nitrocat 1056-XL Compact

Hear what senior autotechs have to say about the AIRCAT Nitrocat 1056-XL compact impact wrench. They’ll provide their reviews on tools they own and have been using every day on...

Voice Your Opinion!

To join the conversation, and become an exclusive member of Vehicle Service Pros, create an account today!