I can be driving my 03 z06 five minutes down the road or it could be after driving for 45 minutes and the SECURITY light will come on the dash with a solid light. The only code that I get when the light is on is P1626. Some times the light will go off after a few minutes and sometimes it will stay on until I turn the vehicle off. Does anybody have any recommendations??
-I tried using different keys.
-I sprayed electrical cleaner on the keys and in the ignition.

 

There's been quite a few threads lately about the SECURITY light coming on while the car is running. Do a search, and you should find plenty of info.

P1626 = Theft Deterrent Fuel Enable Signal Lost

 

A long shot but do you have a load of stuff on your key ring?

I've heard of instances where the weight of the key ring causes the key to move around in the ignition barrel and cause a bad contact with the VATS pellet. If the BCM doesn't see the VATS signal if flashes on the security light.

Try it with just a key and no weight on it and see if it fixes it.

 

I was getting P1631 and the occassional SECURITY light while driving as well. Replaced the ign switch and lock cylinder (pellet reader) and thus far no more problems. But I will need to take another extended trip to see if the issue has truly been fixed.

The difference between the old lock cylinder feel and the new one is very very apparent. Does the key feel loose in the lock cylinder?? I could move the key a couple mm's before in almost all directions but now I cannot.

 

I played with the key wiggling it while at an idle in the drive way tonight. Sure enough after 1a few minutes SERVICE VEHICLE displayed. I ran the codes and the P2626C was active. I then shut off the vechile and tried to restart it and it would not start. I ran the codes and the P1626C displayed along with BCM had No Communication it said. I am going to try the Ignition Switch.

 

just clean the contacts...don't replace it. Your issue is the lock cylinder..

 

Like this

 

Not soo fast. The problem here is that there is no corresponding Theft Deterrent code i.e. B2721-2723 with the P1631. The P1631 by itself suggests that serial communication between the BCM and PCM has be interrupted, and the PCM observes a "fail-enable" mode....which basically allows the car to continue to run....

To the OP, please make sure you are checking codes through the DIC (not a code reader), and you reveal ALL codes.

 

@ the OP, listen to Lucky before me or just about anyone else here...seriously.

Donnie

 

Document ID# 700946
2002 Chevrolet Corvette


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DTC P1626
Circuit Description
The body control module (BCM) produces the theft deterrent crank relay and fuel enable signal when ignition is ON and the proper ignition code voltage value is detected. The powertrain control module (PCM) monitors the fuel enable signal during crank. If the proper signal is present on the Class 2 Serial Data Circuit, the PCM enables the fuel delivery in order to allow the engine to start. If the PCM determines that the fuel enable signal is not present or incorrect while the engine is running, DTC P1626 is set. The engine continues to start and run as long as DTC P1626 is stored. If the problem affects inputs to the VTD signal, the starter motor may be disabled.

Conditions for Running the DTC
The engine is running.

Conditions for Setting the DTC
The PCM has detected a loss of the state of health serial data message from the theft deterrent system.

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 powertrain control module (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 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.
Step
Action
Yes
No

1
Did you perform the Theft Deterrent Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - Theft Deterrent

2

Important
If a loss of DLC data has already been diagnosed, clear this DTC and continue diagnosis with Diagnostic System Check - Engine Controls in Engine Controls - 5.7L.


Is DTC P1631 set as a current code?
Go to Diagnostic Trouble Code (DTC) List
Go to Step 3

3
Inspect for poor connections at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?
Go to Step 5
Go to Step 4

4

Important
The replacement powertrain control module (PCM) must be programmed. Refer to Programming Theft Deterrent System Components .


Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement in Engine Controls - 5.7L.

Did you complete the replacement?
Go to Step 5
--

5
Use the scan tool in order to clear the DTCs.
Operate the vehicle within the conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
Go to Step 2
System OK



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Document ID# 700946
2002 Chevrolet Corvette



ANOTHER CODE DIF!!

Document ID# 677132
2002 Chevrolet Corvette


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Diagnostic System Check - Theft Deterrent
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.

Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.

The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Step
Action
Yes
No

1
Install a scan tool.

Does the scan tool power up?
Go to Step 2
Go to Scan Tool Does Not Power Up in Data Link Communications

2
Turn ON the ignition, with the engine OFF.
Attempt to establish communication with the body control module (BCM), the powertrain control module (PCM), the driver door module (DDM), and the passenger door module (PDM).
Does the scan tool communicate with all of the control modules?
Go to Step 3
Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

3
Select the control module display DTCs function on the scan tool for the BCM, PCM, DDM and the PDM.

Does the scan tool display any DTCs?
Go to Step 4
Go to Symptoms - Theft Deterrent

4
Does the scan tool display any DTCs which begin with a "U"?
Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications
Go to Step 5

5
Does the scan tool display DTC P0601, P0602, P0604 or P0606?
Go to Diagnostic Trouble Code (DTC) List in Engine Controls
Go to Step 6

6
Does the scan tool display DTC B0605 or B1000?
Go to Diagnostic Trouble Code (DTC) List in Body Control System
Go to Step 7

7
Does the scan tool display DTC B2282-B2285, P0562, P0563, P1637 or P1638?
Go to Diagnostic Trouble Code (DTC) List in Engine Electrical
Go to Diagnostic Trouble Code (DTC) List



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Document ID# 677132
2002 Chevrolet Corvette


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