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Home >> Pontiac >> 2004 >> Aztek Base, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 129 (Theft Deterrent System) >> Diagnostic Information and Procedures >> DTC B2955: Security System Sensor Data Circuit >> Test Description
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Test Description

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  Verifies that DTC B2955 is current.
  2. 3:  Tests for proper operation of the circuit in the high voltage range.
  3. 6:  Test for any device that may prevent proper Passlock system operation.
  4. 7:  Tests for a voltage drift within the Passlock sensor.
  5. 8:  Verifies correct signal circuit voltage to Passlock sensor.
  6. 9:  Test for proper operation of the circuit in the low voltage range.
  7. 10:  Tests for high resistance or an open in the 12v reference circuit.
  8. 12:  Tests for a short to ground in the Passlock signal circuit.
DTC B2955

Step Action Values Yes No
Schematic Reference: Theft Deterrent System Schematics 
1 Did you perform the Theft Deterrent Diagnostic System Check? - Go to Step 2  Go to Diagnostic System Check - Theft Deterrent 
2 
  1. Install a scan tool.
  2. Momentarily rotate the ignition switch to CRANK (do not start the vehicle).
  3. Release the ignition switch to ON.
  4. Select the body control module (BCM) display DTCs function on the scan tool.
Does the scan tool display DTC B2955 as a current DTC?		 - Go to Step 3  Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3 
  1. Install a scan tool
  2. Momentarily rotate the ignition switch to CRANK (do not start the vehicle).
  3. Release the ignition switch to ON.
  4. With a scan tool, observe the Passlock data voltage in the Body Control Module Security Data list.
Does the scan tool indicate that the Passlock data voltage is within the specified range?		 0.4-4.9 V Go to Step 4  Go to Step 8 
4 Have you replaced the Passlock sensor on this vehicle? - Go to Step 5  Go to Step 6 
5 Have you performed a Passlock learn procedure after replacing the Passlock sensor? - Go to Step 7  Go to Step 19 
6  Inspect the area around the ignition lock cylinder for any device which could create a magnetic field (audio speaker, magnet, ect.).
Is there a magnet device near the ignition lock cylinder?		 - Go to Step 17  Go to Step 7 
7  With a scan tool, observe the Passlock data voltage for one minute.
Does the scan tool indicate that the Passlock data voltage is changing more than the specified value?		 +/- 0.02 volts Go to Step 16  Go to Step 8 
8 
  1. Turn OFF the ignition.
  2. Disconnect the Passlock sensor.
  3. Turn ON the ignition with the engine OFF.
  4. With a scan tool observe the Passlock Data Voltage in the Body Control Module Security Data list.
Does the scan tool indicate that the Passlock Data Voltage is greater than the specified value?		 4.9 volts Go to Step 9  Go to Step 12 
9 
  1. Turn OFF the ignition.
  2. Connect a 3 amp fused jumper wire between the signal circuit of the Passlock sensor and the ground circuit of the Passlock sensor.
  3. Turn ON the ignition with the engine OFF.
  4. With a scan tool observe the Passlock Data Voltage in the Body Control Module Security Data list.
Does the scan tool indicate that the Passlock Data Voltage is less than the specified value?		 0.4 volts Go to Step 10  Go to Step 11 
10 
  1. Disconnect the fused jumper wire.
  2. Measure the voltage between the 12v reference circuit of the Passlock sensor and ground circuit of the Passlock sensor.
Does the voltage measure less than the specified value?		 12.0 volts Go to Step 13  Go to Step 16 
11 Test the signal circuit of the Passlock sensor for a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 21  Go to Step 14 
12  Test the Passlock sensor 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 21  Go to Step 15 
13 Test the 12v reference circuit of the Passlock sensor for a high resistance or an open. Refer toCircuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 21  Go to Step 14 
14 Test the ground circuit of the Passlock sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 21  Go to Step 15 
15 Inspect for poor connections and the BCM. 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 21  Go to Step 20 
16 Inspect for poor connections and 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 21  Go to Step 18 
17 Remove the device creating the magnetic force.
Did you find and correct the condition?		 - Go to Step 21  -
18 Replace the Passlock sensor. Refer to Ignition Lock Cylinder Case Replacement in Steering Wheel and Column.
Did you complete the repair?		 - Go to Step 19  -
19 Perform the Programming Theft Deterrent System Components  .
Is the repair complete?		 - Go to Step 21  -
20
IMPORTANT: When replacing the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.
Replace the body control module. Refer to Body Control Module Replacement in Body Control System.Did you complete the replacement?		 - Go to Step 21  -
21 You may have to wait up to 10 minutes in order to reset the BCM and synchronize all of the Passlock components.
  1. Use the scan tool in order to clear the DTC's.
  2. Turn OFF the ignition.
  3. Momentarily rotate the ignition switch to CRANK (do not start the vehicle).
  4. Release the ignition switch to ON.
  5. Select the body control module display DTC's function on the scan tool.

Does the DTC reset?		 - Go to Step 3  Go to Step 22 
22 Attempt to start the vehicle.
Does the engine start and run?		 - System OK Go to Step 3 
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