Diagnostic Aids

When vehicle is moving greater than 3 MPH, Tech 1 should indicate a vehicle speed. Code P0502 indicates an intermittent and may not set immediately or under all conditions. Check sensor circuits for proper connections. Ensure they are clean and tight and harness is correctly routed.

Fig 1: Code P0501/P0502 Schematic (3.8L) VSS Circuit

Fig 2: Code P0501/P0502 Flow Chart (3.8L) VSS Circuit