Circuit Description
The Vehicle Theft Deterrent module produces the theft deterrent fuel enable signal when the ignition is on and the proper key resistor pellet is sensed by the Vehicle Theft Deterrent Module. The PCM monitors the fuel enable circuit during crank. If the proper signal is present on the 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 is incorrect while the engine is running, DTC P1626 will be set. The engine will continue to start and run as long as DTC P1626 is stored and the fault condition effects only the Vehicle Theft Deterrent fuel enable circuit.
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 will not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data. |
Conditions for Clearing the MIL/DTC
| • | A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using the scan tool Clear Info function. |
Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation. Check for:
| • | Poor connection. Inspect the PCM and Theft Deterrent module harness and connectors for improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. Refer to Intermittents and Poor Connections Diagnosis . |
| • | Damaged harness. Inspect the wiring harness for damage. |
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:
-
This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||
2 |
Important: : Before continuing diagnosis, ensure that the vehicle battery is fully charged. Attempt to start vehicle. Does engine crank? | -- | Refer to Vehicle Theft Deterrent (VTD) System Check in Theft Deterrent. | |
3 |
Does voltage measure near the specified value? | 5.0V | ||
4 |
Is the frequency between the specified values? | 40-60 Hertz | ||
5 |
Does the vehicle start and continue running? | -- | Go to Diagnostic Aids | |
6 |
Was a problem found? | -- | ||
7 |
Was a problem found? | -- | ||
8 |
Was a problem found? | -- | ||
|
Important: : Replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the repair? | -- | -- | ||
10 | Replace the Theft Deterrent module. Refer to Theft Deterrent Module Replacement in Theft Deterrent. Did you complete the repair? | -- | -- | |
11 |
Does VTD Fuel Disable display Inactive? | -- | Repair complete |
