🔧 ECM Diagnostics: Method 2 🔧 Discover the second method to diagnose an ECM! Here's an example on a Detroit DDEC III 1️⃣ Connection: We hook the ECM to a bench harness for communication. 2️⃣ Diagnostic Codes: We used Detroit Diagnostic Link and found it has non-volatile memory failure and zero engine hours. 3️⃣ Result: This DDEC III ECM (12.7 Detroit) needs repair—100% confirmed! 🔍 Advanced Testing: I also manually check voltages and inspect signals in our lab for injector or sensor issues us