Powertrain Chart 3, Powertrain Ground Check

The 3 vehicle grounds are essential for proper powertrain system operation. They are:

• Circuit G104, located on lower right front of engine, right of starter motor.
• Circuit G301, located behind right kick panel.
• Circuit G401, located on left rear seat to left of diagonal brace.

Circuit G401 is ground location for fuel pump. Circuit G104 is cooling fan and A/C compressor clutch ground. Circuit G301 is ground for all powertrain electronics, including PCM.

Loose or poor ground connections may cause a variety of problems, including flickering telltales, PCM codes and several driveability problems. POWERTRAIN GROUND CHECK should be performed when referred to by other diagnostics or when erratic or intermittent problem is present.

Fig 1: Powertrain Chart 3 Schematic, Powertrain Ground Check

Courtesy of GENERAL MOTORS CORP.

Fig 2: Powertrain Chart 3 Diag. Flow Chart, Powertrain Ground Check

Courtesy of GENERAL MOTORS CORP.