Diagnostic Aids

A Scan tester should indicate vehicle speed whenever vehicle is in motion. A faulty or misadjusted Park/Neutral switch can result in a false Code 24. Use Scan tester to check for proper signal while vehicle is in Drive position. For intermittent inspection, see INTERMITTENTS in TESTS W/O CODES article in the ENGINE PERFORMANCE Section.

Fig 1: Code 24 Schematic - VSS Circuit

Courtesy of ISUZU MOTOR CO.

Fig 2: Code 24 Flow Chart - VSS Circuit

Courtesy of ISUZU MOTOR CO.