Need help car won'tstart dic code p1631 hc
Thread Starter
Burning Brakes
Joined: Apr 2003
Posts: 1,004
Likes: 0
From: Miami Fl
Need help car won'tstart dic code p1631 hc
Need help my car won't start. I checked the dtc codes and have a 10 pcm -1631 hc code. A web site states that my password code is incorrect. Does anyone know what that means?
Is that the key is to worn out? A sensor? What?
Any help is greatly appreciated. Thanks in advance.
Is that the key is to worn out? A sensor? What?
Any help is greatly appreciated. Thanks in advance.
Melting Slicks
Joined: Oct 2007
Posts: 2,383
Likes: 13
From: Kinston North Carolina
DTC P1631
Circuit Description
The powertrain control module (PCM) controls the fuel injector operation and the starter operation based on a vehicle theft deterrent (VTD) password from the vehicle body control module (BCM). When the ignition is first turned ON, the BCM sends a programmed theft deterrent password to the PCM. The PCM acknowledges the password and responds to the BCM that normal fuel injector and starter operation will continue. If the PCM detects an incorrect password, a theft deterrent system failure, or an attempted vehicle theft, DTC 1631 will set. The engine will not start or crank as long as the condition is present.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The PCM detects an incorrect password from the VTD system.
The condition is present for less than 1 second.
Action Taken When the DTC Sets
The body control module (BCM) send a class to message to the instrument panel cluster (IPC) to illuminate the SECURITY indicator.
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 a scan tool.
Diagnostic Aids
DTC P1631 indicates that the vehicle theft deterrent password that the PCM has learned does not agree with the password received from the VTD system. This condition can occur if an incorrect key is used when attempting to start the vehicle, or if the BCM has been replaced and the PCM Password Learn function has not been enabled. If the BCM has been replaced, the password must be relearned.
Circuit Description
The powertrain control module (PCM) controls the fuel injector operation and the starter operation based on a vehicle theft deterrent (VTD) password from the vehicle body control module (BCM). When the ignition is first turned ON, the BCM sends a programmed theft deterrent password to the PCM. The PCM acknowledges the password and responds to the BCM that normal fuel injector and starter operation will continue. If the PCM detects an incorrect password, a theft deterrent system failure, or an attempted vehicle theft, DTC 1631 will set. The engine will not start or crank as long as the condition is present.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The PCM detects an incorrect password from the VTD system.
The condition is present for less than 1 second.
Action Taken When the DTC Sets
The body control module (BCM) send a class to message to the instrument panel cluster (IPC) to illuminate the SECURITY indicator.
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 a scan tool.
Diagnostic Aids
DTC P1631 indicates that the vehicle theft deterrent password that the PCM has learned does not agree with the password received from the VTD system. This condition can occur if an incorrect key is used when attempting to start the vehicle, or if the BCM has been replaced and the PCM Password Learn function has not been enabled. If the BCM has been replaced, the password must be relearned.
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