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Fuel Pump Amperage Test

NOTE: Perform FUEL PUMP AMPERAGE TEST in conjunction with FUEL PUMP CAPACITY TEST, FUEL PUMP PRESSURE TEST and FUEL PRESSURE LEAKDOWN TEST.

Ensure fuel tank temperature is more than 50°F (10°C). Connect DRB Low Current Shunt (LCS) adapter into DRB-III scan tool SET 1 connector. See Fig 1. Connect DRB-III scan tool to Data Link Connector (DLC). Connect test lead cables into 10-amp (10A +) and common (-) connectors on LCS. Access MAIN MENU on scan tool. Press DVOM button.

Fig 1: Identifying DRB-III Low Current Shunt (LCS) Adapter
Courtesy of DAIMLERCHRYSLER CORP.

NOTE: Changing scan tool from 2-amp to 10-amp scale must be done to avoid damage to scan tool or LCS adapter.

Use left/right arrow keys to highlight CHANNEL 1 function on scan tool. Press ENTER 3 times. Use up/down arrow keys to high light RANGE on scan tool. Press ENTER to change from 2-amp scale to 10-amp scale. Remove Power Distribution Center (PDC) cover and remove fuel pump relay. Depending on make or model of vehicle, 3 different relays are used. Use the following procedure for appropriate relay:
1. Type 1 Fuel Pump Relay
  
  Attach test leads from LCS adapter into PDC relay cavities No. 30 and 87. See Fig 2.
2. Type 2 Fuel Pump Relay
  
  Attach test leads from LCS adapter into PDC relay cavities No. 30 and 87. See Fig 3.
3. Type 3 Fuel Pump Relay
  
  Attach test leads from LCS adapter into PDC relay cavities No. 3 and 5. See Fig 4.
  
  Fig 2: Identifying Type 1 Fuel Pump Relay
  Courtesy of FORD MOTOR CO.
  
  Fig 3: Identifying Type 2 Fuel Pump Relay
  Courtesy of DAIMLERCHRYSLER CORP.
  
  Fig 4: Identifying Type 3 Fuel Pump Relay
  Courtesy of FORD MOTOR CO.
Fuel pump will be operated when LCS adapter leads are connected to relay cavities. Read fuel pump amperage from DRB scan tool screen. Amperage should be less than 10 amps. If amperage is 10 amps or more, replace fuel pump module assembly. If amperage is less than 10 amps and FUEL PUMP PRESSURE, FUEL PUMP CAPACITY and FUEL PRESSURE LEAK DOWN test readings are okay, fuel pump module is okay.