Diagnostic Aids

Visually inspect circuit No. 423 (IC circuit) for chafed wiring (short to ground). Inspect circuit No. 424 (by-pass circuit) for cut wire and good OCM and module contact. Wiggle wires while monitoring scan tester to see if codes will reset.

Fig 1: Codes 41 & 42 Schematic Simultaneous, By-Pass Open Or Grounded

Fig 2: Codes 41 & 42 Diagnostic Flow Chart Simultaneous, By-Pass Open Or Grounded