For 1990-2009 cars

### Circuit Description

The Passlock system is provided in order to prevent vehicle theft if the ignition lock cylinder is forced to rotate or the ignition switch is operated while separated from the ignition lock cylinder case. The passlock module provides security system sensor power and low reference for the passlock sensor. The passlock module also measures the security system sensor voltage. When the correct key is used to start the vehicle, a magnet on the lock cylinder passes close to the passlock sensor within the ignition lock cylinder case. The magnet activates the security hall effect sensor in the passlock sensor which completes a circuit from the security sensor signal circuit through a resistor to the security sensor low reference circuit. The resistance value will vary from vehicle to vehicle. The passlock module will measure the voltage on the security sensor signal circuit and compare this voltage to a previously learned voltage. If the voltage measured is within the valid range, the passlock module will send a class 2 message to the powertrain control module (PCM) to enable vehicle starting. If the voltage measured is not within the valid range, a class 2 message will be sent to the PCM to disable starting of the vehicle.

### Conditions for Setting the DTC

• | Received a fuel disabled password from the body control module (BCM).

| Or

• | An undecided password was sent from the BCM.

### Action Taken When the DTC Sets

• | The PCM will record operating conditions at the time during which the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffers.

• | A history DTC stores

• | The fuel system is disabled by the PCM.

### Conditions for Clearing the MIL/DTC

• | A history DTC will clear after 40 consecutive warm up cycles without a fault.

• | A scan tool can clear current and history DTCs.

### Diagnostic Aids

Attempting to start the vehicle by bypassing the Passlock system or by substituting parts without performing the Programming Theft Deterrent System Components procedure may set a DTC P1631 and a P1632.

If no password is received, a DTC U1064 and P1632 may be set.

An intermittent may be caused by a poor connection, a rubbed through wire insulation, or by a wire broken inside the insulation.

Thoroughly check any suspected circuitry for the following items:

• | Backed out terminals or improper mating

• | Broken locks

• | Improperly formed or damaged terminals

• | Poor terminal to wiring connections

• | Physical damage to the wiring harness

• | Corrosion

### Test Description

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

1. The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when the fault occurred. The scan tool stores this data for later reference.

2. The PCM may not have learned the new password. Refer to Password Learn Procedure portion of the service manual.

3. The scan tool can display whether or not the BCM has received and learned the password from the lock cylinder. If the password is not received, the reason the PCM set this DTC may be due to a password that has not yet been learned due to a component being replaced or a problem in the BCM or a VTD component.

4. Replacement VCMs/PCMs must be reprogrammed. A reprogrammed PCM does not require the password learn procedure to be performed. The password will be learned on the first ignition cycle.

5. A Passlock™ theft deterrent, or BCM DTC being set indicates that a Passlock™ component may be malfunctioning.

6. If no DTCs were set and the BCM has not learned (received) a password from the ignition lock cylinder, the BCM may need to learn the password, or may be malfunctioning.

7. If no malfunctions are present at this point and no additional DTCs were set, refer to Diagnostic Aids for additional checks and information.

#### DTC P1632 - Fuel Disabled Due to Vehicle Theft Deterrent (VTD)

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Theft Deterrent System Schematics
1 | Did you perform the Vehicle Theft Deterrent (VTD) Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Theft Deterrent
2 | Was DTC P1626, or P1631 also set? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 3
3 |

1. Perform the Programming Theft Deterrent System Components Procedure. Refer to Programming Theft Deterrent System Components .
2. Attempt to restart the engine.

Does the engine start and continue to run?

Go to Step 8

Go to Step 4

4 |

1. Install a scan tool.
2. Display the data list for the BCM.

Does the scan tool indicate that the Passlock™ Data is Valid?

Go to Step 5

Go to Step 6

5 | Important: The replacement PCM must be programmed. Replace the PCM.

• | For 2.2L, refer to Powertrain Control Module Replacement in Engine Controls-2.2L (L61).

• | For 3.0L, refer to Engine Control Module Replacement in Engine Controls-3.0L (L81)

Is the action complete?

Go to Step 8

--

6 | Invalid data must be coupled with the presence of VTD system DTCs. Are there any VTD system DTCs set? | Go to Diagnostic Trouble Code (DTC) List | Go to Step 7
7 | Important: The replacement BCM must be programmed. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Is the action complete? | Go to Step 8 | --
8 |

1. Using the scan tool, clear the DTCs.
2. Start engine.
3. Idle the engine at the normal operating temperature.
4. Operate the vehicle within the conditions for setting this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic ran and passed?

Go to Step 9

Go to Step 2

9 | Check to see if any additional DTCs are set. Does the scan tool display any DTCs that you have not diagnosed? | Go to Diagnostic Trouble Code (DTC) List | System OK