Current Consumption

On CLK class and E class models, disconnect fuel pump relay (K27). Connect DVOM to fuel pump relay socket terminals No. 2 and 8. On ML320, disconnect fuel pump relay (k3). Connect DVOM to fuel pump relay socket terminals No. 30 and 87. On all models, turn ignition on. DVOM should indicate 4-9 amps. If amperage is within specification, test is complete. If amperage is not within specification, possible cause is faulty fuel pump. Repair as necessary.