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Code 46, Pass-Key System: Notes

The Personal Automotive Security System (PASS-KEY) is designed to disable vehicle operation if an incorrect ignition key or starting procedure is used. The ECM applies and monitors a 5-volt signal to the Central Control Module (CCM). When CCM determines proper key and starting technique is being used, it will complete the PASS-KEY circuit, modifying the ECM-monitored voltage signal and enabling the starter relay. ECM will then allow enablement of the fuel injector circuits and permit vehicle to start and run. If monitored circuit No. 229 becomes open or shorted to ground, Code 46 will set and vehicle will not start.

NOTE: Test numbers refer to test numbers on diagnostic chart.

Test Number 1)  If the engine cranks and a Code 46 is stored, it indicates the CCM, which modifies the ECM-monitored signal, is not operating or circuit No. 229 is open or shorted to ground. If CCM is okay and circuit No. 229 is not open or shorted to ground, the ECM may be at fault, but this is not likely.

Test Number 2)  If Code 46 is stored and the engine will not start, it indicates an anti-theft system problem, an incorrect ignition key or starting procedure is used.

NOTE: If condition is intermittent, see INTERMITTENTS in the TESTS W/O CODES article in this section.
Fig 1: Code 46, Schematic, Pass-Key System
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Fig 2: Code 46, Flow Chart, Pass-Key System
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