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 input 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.
Conditions for Setting the DTC
| • | The ignition switch is ON. |
| • | The Passlock module is unable to produce the 9-16 volts required for the Passlock™ Sensor operation. This may be due to a module, wiring, or sensor problem. |
Action Taken When the DTC Sets
| • | The vehicle will not run if the fault occurs before the vehicle is started. The security telltale will be ON. |
| • | If the vehicle is running when the fault occurs, the Passlock™ Module will be in the fail enabled mode allowing the vehicle to start and run. The security telltale will be ON. |
Conditions for Clearing the DTC
| • | The DTC will clear after an ignition cycle has occurred without the fault. |
| • | Passlock module history codes will be cleared after 100 ignition cycles with no current codes active. |
| • | Using a scan tool. |
Diagnostic Aids
| • | When replacing the Passlock™ Sensor, all sensor components lock, sensor, filter, and harness are included as a replacement part and must be replaced. |
| • | Use the scan tool in order to inspect the Passlock™ data voltage and the Passlock™ code. |
| • | Perform a visual check of the wiring and the connectors. |
| • | Inspect the Passlock sensor harness for an intermittent or a short to battery. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verifies the existence of this current DTC.
-
This step tests for a short to ground in the Passlock™ sensor or the pigtail harness.
-
This step tests for a short to ground in the 12 V reference circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Theft Deterrent (VTD) Diagnostic System Check? | -- | Go to Step 2 | |
Does the scan tool display DTC B2947 as a current DTC? | -- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | |
Does the voltage measure within the specified range? | B+ | Go to Step 6 | Go to Step 4 | |
Test the 12 V reference circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 5 | |
5 | Inspect for poor connections at the Passlock module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 7 |
6 | Inspect for poor connections at the Passlock™ sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 8 |
7 | Replace the Passlock module. Refer to Theft Deterrent Module Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
8 | Replace the Passlock™ sensor in the electronic column lock module assembly. Refer to Electronic Column Lock Module - Disassemble - Off Vehicle or Electronic Column Lock Module - Assemble - Off Vehicle in Steering Wheel and Column. Did you complete the replacement? | -- | Go to Step 9 | -- |
9 | Perform the PASSLOCK Reprogramming Auto Learn procedure. Is the repair complete? | -- | Go to Step 10 | -- |
10 |
Does the DTC reset? | -- | Go to Step 3 | System OK |
