Circuit Description

1999 GMC Savana Special 7.4 JSECTION Circuit Description

The Passlock™ module supplies power to the Passlock™ sensor on CKT 812.

When the Passlock™ sensor is powered and the ignition switch is rotated to the CRANK position, the hall effect security sensor will latch holding an internal code value. The Passlock™ module will compare this code to the value that the Passlock™ module measured in the last ignition cycle. If the latched value is the same as the last ignition cycle value, the test has passed. When the ignition switch is turned to the OFF position, the sensor is no longer powered and the sensor latch circuit resets.

In the next ignition cycle, the Passlock™ sensor waits for an ignition switch crank input. The Passlock™ sensor compares the ignition switch crank to the last recognized code. If the Passlock™ sensor power is shorted to ground, the sensor circuitry will not function and produce the required code.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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