Circuit Description
The Theft Deterrent Module produces the Fuel Enable Signal based on input from the door lock cylinders, shock sensor, and rear compartment lock cylinder. The PCM monitors the Fuel Enable Signal during crank. If the proper signal is present on the Theft Deterrent Fuel Enable Circuit, the PCM enables fuel delivery to allow the engine to start. If the PCM detects that the fuel enable signal is not present or incorrect while an attempt is made to start the engine, DTC P1626 will set. A problem that affects inputs to the Theft Deterrent Module will also result in a missing or incorrect fuel enable signal to the PCM. The engine will not start as long as either condition is present. For further information on the Theft Deterrent System, Refer to Vehicle Theft Deterrent (VTD) System Check in Theft Deterrent.
Conditions for Running the DTC
| • | DTC 1629 is not present. |
| • | An attempt is made to start the engine. |
Conditions for Setting the DTC
| • | The PCM detects an incorrect signal on the Theft Deterrent Fuel Enable Circuit. |
| • | The above conditions are present for longer than 2 seconds. |
Action Taken When the DTC Sets
The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.
Conditions for Clearing the MIL/DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | The PCM receives a clear code command from the scan tool. |
Diagnostic Aids
Inspect for the following:
Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | Loose terminal connection |
| - | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| - | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
| • | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On Board Diagnostic (OBD) System Check? | -- | ||
2 |
Important: : Before continuing diagnosis, ensure that the vehicle battery is fully charged. Attempt to start the engine. Does the engine crank? | -- | Go to Diagnostic System Check - Engine Electrical in Engine Electrical | |
3 |
Does voltage measure near the specified value? | 5.0V | ||
4 |
Is the frequency between the specified values? | 40-60 Hz | ||
5 |
Does the vehicle start and continue running? | -- | Go to Diagnostic Aids | |
6 | Test the vehicle theft deterrent fuel enable circuit for an open, short to ground, or short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
7 | Test the theft deterrent fuel enable circuit for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | ||
8 | Inspect for poor connections at the Theft Deterrent Module. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | Go to Vehicle Theft Deterrent (VTD) System Check in Theft Deterrent | |
|
Important: : The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the repair? | -- | -- | ||
10 |
Does VTD Fuel Disable display Active? | -- | System OK |
