Code 46, Vehicle Anti-Theft System: Notes

Vehicle Anti-Theft System (VATS) is designed to disable vehicle operation if an incorrect ignition key or starting procedure is used. Anti-theft decoder module sends a signal to ECM if correct key is used. If proper signal does not reach ECM on circuit No. 229, ECM will not pulse injectors and vehicle will not start. Code 46 will set.

1. If engine cranks and a Code 46 is stored, VATS decoder module, which generates signal to ECM, is not operating or circuit No. 229 is open or shorted to ground. If VATS decoder module is okay, ECM may be at fault; this is not likely.
2. If Code 46 is stored and engine will not start, an anti-theft system problem exists or an incorrect ignition key or starting procedure is being used.