Chevrolet Impala - Popular Questions, Answers, Tips & Manuals

DTC P1631 Theft Deterrent Fuel Enable Signal Not Correct

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.

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 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.

Did you perform the Diagnostic System Check - Vehicle?
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
Perform the Password Learn Procedure. Refer to Programming Theft Deterrent System Components .
Did you complete the procedure?
System OK

30-Minute Learn Procedure
Turn ON the ignition, with the engine OFF.
Attempt to start the engine, then release the key to ON; the vehicle will not start.
Observe the SECURITY telltale. After approximately 10 minutes, the telltale will turn OFF.
Turn OFF the ignition, and wait 5 seconds.
Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes. The vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.
Important: The vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
Start the engine. The vehicle has now learned the Passlock™ Sensor Data Code and/or password.
With a scan tool, clear any DTCs if needed. History DTCs will self clear after 100 ignition cycles.

2005 Chevrolet... | 43 views | 0 helpful votes

doesnt it still have a valid warranty??

Chevrolet Impala... | 34 views | 1 helpful votes

Building on Mr Hooper's answer ... if you have managed to short something out as part of the ignition switch it could be one of the RELAYs in the engine is near the passenger side firewall. I would evaluate the "STRTR" relay which is one of the larger ones in the box on the upper right hand corner.
Sometimes if there are 2 identical relays in a box you just switch them to see if that changes anything, but for this Impala it does not look like there is a twin relay to play with.
If you are handy with a multimeter you can check the relay ... watch video for some pointers to do that ... even if you do not have the internal wiring of the relay
Good luck on your troubleshooting.
None of the handful of fuses in the passenger compartment (shotgun side down by the kick plate) look like they have anything to do with the ignition/starting circuit.

2008 Chevrolet... | 35 views | 0 helpful votes

I take help from online websites that have this service like helping in repair some like reliable-store have instant help.. others are a bit slow which I don't prefer... rest is up to u.. U can also get free manuals

2000 Chevrolet... | 37 views | 0 helpful votes

There has been a RECALL for this vehicle with power steering problems. Check your power steering fluid and if it's OK head to a dealer and ask about the recall. I hope this helps. Take care.

Chevrolet Impala... | 27 views | 1 helpful votes

P0442 Chevy Impala: Evaporative Emission System Leak Detected ...

Jul 29, 2018 - Chevy Impala P0442 Code Symptoms. The P0442 code on a Chevy Impala will often be thrown after the engine has a hard time starting after refueling. ... EVAP Canister Purge Valve- The most common culprit with the P0442 trouble code and the Chevy Impala is going to be the vapor canister ...

Chevrolet Impala... | 29 views | 0 helpful votes

There is not a reset switch on a 2013 Impala

2013 Chevrolet... | 24 views | 0 helpful votes

Tip & How-To about Cars & Trucks
Resetting a Vehicle Anti-Theft System
This is how you reset an anti theft system if you have the anti-theft light on, or your car is cranking, but you have no spark.

Doing a full reset of the anti-theft system.

Disconnect both battery leads for at least two hours.
Hold the negative and positive leads together for 5 minutes to fully discharge any power.
Put the key in the ignition, but not turned on. VERY IMPORTANT!
Connect the positive lead.
Connect the negative lead in one swift movement.
Wait 15 minutes for the system to fully reset.
Posted by Andrew... on Jan 14, 2018

Resetting Vehicle Anti Theft System

2003 Chevrolet... | 21 views | 0 helpful votes

there's a site reliable- store
all heavy equipment repair issues servicing, loading, wiring, engine problems everything is covered here its a must try for those who aren't fully equipped with tools or knowledge

Chevrolet Impala... | 53 views | 0 helpful votes

Battery is going out or not enough cold cranking amps, have the battery tested any auto part store does it for free.

2011 Chevrolet... | 33 views | 0 helpful votes

I got this free Pdf manual from reliable-store for free and I don't think Ive visited a mechanic or fixya for help for more than 3-4 times out of the 20 times I fixed the chipper in these 4 years

Chevrolet Impala... | 36 views | 0 helpful votes

You need to remove the plastic intake manifold cover .

Chevrolet Impala... | 32 views | 0 helpful votes

This motor has a timing chair and I believe that it is a non interference enginr

Chevrolet Impala... | 20 views | 0 helpful votes

Take car to local parts store. Most will scan for free and tell you which one is bad. No sense in changing all if not needed

Chevrolet Impala... | 20 views | 0 helpful votes

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