EXPERTEC Technical Service Bulletins (11-94-24)

EXPERTEC TECHNICAL SERVICE BULLETINS

TECHNICAL SERVICE BULLETIN

PASS-KEY STARTER INHIBIT OPERATION

Model(s): 1995 Oldsmobile Aurora

Bulletin No.: 11-94-24

Section: Engine Fuel And Emissions

Date: November 1, 1994

SERVICE INFORMATION

The 1995 Aurora has a starter inhibit function that prevents engagement of the starter once the engine is running. See Fig 1 .

HOW IT WORKS

The PCM (Powertrain Control Module) looks for an engine RPM signal greater than engine cranking speed. Once the engine is running, the PCM provides a ground through the starter disable circuit of the PCM. This ground allows the starter disable control in the PASS-Key decoder module to energize, which opens the starter enable relay control. Once the relay control is prevented from closing, any ignition key input is ignored and the starter is prevented from engaging while the engine is running.

The Tech 1 will display a "PKEY STARTER INH" display under ENGINE MESSAGE 1 SCAN DATA VALUES. This will tell you whether or not the starter is inhibited.

The starter inhibit input circuit in the PCM has a (5) five second delay after the engine is running before the PCM will provide a ground to the PASS-Key module to prevent crank during engine run. If the engine is started and the ignition key is cycled to start position within 5 seconds, the starter MAY engage and damage the flywheel.