Mercedes Benz

P1600 Voltage supply P1601 Voltage supply P1602 Voltage supply The OBD-II diagnostic trouble codes P1600, P1601, and P1602 all relate to issues with the voltage supply to the vehicle's engine control module (ECM) or powertrain control module (PCM), as well as related communication faults. The exact meaning of each code can vary between different car manufacturers and models.   Common causes for these codes The appearance of these codes often indicates a problem with the vehicle's electrical system, which affects the power or communication to the ECM. Weak or failing battery:  Low battery voltage is a very common cause, as the ECM needs a stable power supply to function correctly. Corroded or loose battery connections:  Poor connections at the battery terminals can cause intermittent power loss to the ECM, triggering these codes. Faulty alternator or charging system:  A malfunctioning alternator can fail to charge the battery properly, leading to low system voltage. P...