1998 Mercedes SLK230 P0806 Code: Check Engine Light On, Won't Crank, Fan Stays On After Shutdown

Model: 1998 Mercedes 230 SLK Fault Code: P0806 Posted: 2017-11-17 06:03

A previous member reported their 1998 Mercedes SLK230 was running normally until the check engine light illuminated and a P0806 diagnostic code appeared. Despite following common repair steps—replacing the electromagnetic clutch pulley, repairing and replacing the K40 sensor, and having the ECM repaired—the code persists. After reassembling all components, the vehicle now fails to crank; instead, it produces only a clicking sound. The battery is fully charged and shows no signs of failure. A new issue has emerged: when the ignition key is removed, the cooling fan continues running for an extended period—something that did not occur before. This 1998 SLK230 is equipped with an automatic transmission. Given the persistent P0806 code and the sudden loss of cranking ability, what should be investigated next? The user is concerned about potential damage from improper repairs or underlying electronic faults in the transmission control system.