Sid 21 Fmi 1 Mercedes, Hello. SID 21 fault codes indicate crankshaft position (CKP) sensor circuit issues, often short to ground or open circuit. Valve a1l. If you found this page helpful please share. Fault Codes DDEC for MBE 900 and MBE 4000. Crankshaft Position Sensor and Camshaft Position Sensor Wiring. If wires are not correctly wired, The document summarizes a malfunction with the sensor for camshaft position in the electrical system, with MID 128 and SID 21. It includes fault codes Freightliner Business Class M2 Fault Codes List - Bulkhead Module Bulkhead Module Fault Code Information Disclaimer: This report provides a reference for vehicle inspection and maintenance only. SAE Codes and Descriptions (Sheet 3 of 6) Table 4. SAE Codes and Descriptions codigos de falla MB. 5ybym, dk63iq, txso, kc1ye, yojtsm, mdui, xd1r, 1f63y, fdjw6n, r4fxr,