Fuel Pump Circuit Wiring Diagram (1996 3.1L V6 Buick Century)

APPLIES TO: This fuel pump circuit wiring diagram applies to the following vehicles:

• 3.1L V6 Buick Century: 1996.

Basic Operating Theory Of The Fuel Pump Relay

The fuel pump relay allows the PCM to control when battery power is sent to the in-tank fuel pump.

When the ignition key is turned to the ON position, the PCM energizes the relay for approximately 2 seconds. This primes the fuel system by building fuel pressure before the engine is started.

If the engine isn't started during this 2-second prime cycle, the PCM switches the relay OFF. As soon as the engine is cranking and the PCM detects ignition reference signals, it energizes the relay again so the fuel pump can run continuously.

The system also includes a backup oil pressure switch. Once engine oil pressure reaches about 4 PSI (28 kPa), the switch closes and provides an alternate path for battery power to the fuel pump. This allows the engine to continue running even if the fuel pump relay fails.

If the relay stops working, the engine may crank for an extended period before starting or may not start at all, depending on whether the oil pressure switch is able to power the fuel pump.

FUEL PUMP TESTS: How To Test The Fuel Pump (1994-2005 3.1L V6 Buick Century).

Other Fuel Pump Wiring Diagrams

• Fuel Pump Circuit Wiring Diagram (1994-1995 3.1L V6 Buick Century).
• Fuel Pump Circuit Wiring Diagram (1997 3.1L V6 Buick Century).
• Fuel Pump Circuit Wiring Diagram (1998-1999 3.1L V6 Buick Century).
• Fuel Pump Circuit Wiring Diagram (2000-2001 3.1L V6 Buick Century).
• Fuel Pump Circuit Wiring Diagram (2002-2005 3.1L V6 Buick Century).

More 3.1L V6 Buick Century Tutorials

You can find a complete list of 3.1L V6 Buick Century tutorials and wiring diagrams in this index:

• 3.1L V6 Buick Century Index of Articles.

Here's a sample of the tutorials you'll find in the index:

• How To Test The TPS With A Multimeter (1997-2005 3.1L V6 Buick Century).
• Common Causes Of Spark Plug Failure (1994-2005 3.1L V6 Buick Century).
• How To Test For A Blown Head Gasket (1994-2005 3.1L V6 Buick Century).
• How To Test Engine Compression (1994-2005 3.1L V6 Buick Century).