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B2947

Diagnostic Chart:




Schematic:




CIRCUIT DESCRIPTION,
The Body Control Module (BCM) supplies power to the passlock(TM) sensor on CKT 1459.

When the Passlock(TM) sensor is powered and the ignition switch is rotated to the CRANK position, the hall effect security sensor will latch and provide a code to the BCM. The BCM will then compare this code to the code in the previous ignition cycle. If the latched value is the same as the last ignition cycle value, the test has passed. When the ignition switch is switched to the OFF position, the sensor is no longer powered and resets the sensor latch circuit. In the next ignition cycle, the Passlock(TM) sensor waits for an ignition switch crank input and verifies the sensor code and compares the sensor code to the last stored valid code.

CONDITIONS FOR RUNNING THE DTC
The ignition switch is cycled to CRANK and released to ON.

CONDITIONS FOR SETTING THE DTC
^ The ignition switch is in the ON position.
^ The BCM is unable to produce the 9-16 volts required for the Passlock(TM) sensor operation. This may be due to a module, a wiring, or a sensor problem.

ACTION TAKEN WHEN DTC SETS
^ The BCM turns off the Passlock (TM) power as long as the current code is set.
^ If the DTC sets during cranking, the car will not start and the theft indicators remains illuminated.
^ If the DTC sets while the engine is running, the car will start on future attempts and the theft indicators flashes.
^ The SERVICE VEHICLE SOON indicators illuminates.

CONDITIONS FOR CLEARING THE DTC
^ Current DTCs will clear after one ignition cycle if the malfunction is no longer present.
^ All of the BCM history codes are cleared after 100 ignition cycles (from OFF to ON) with no current codes active during the 100 ignition cycles.

DIAGNOSTIC AIDS
^ DTC B2958 may also set along with this code.
^ Inspect for a poor connection at the Passlock (TM) Sensor and the BCM.
^ It the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while wiggling the wiring and connectors. This action often causes the malfunction to appear.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. Verifies the existence of this current DTC.
3. Tests for an open or short to ground in the Passlock(TM) sensor power circuit.