2000 STS with electrical problems?

[Logan]

Any chance this is a flood car?

As for the seat belt pre-tensioners. They can deploy without frontal bag deployment. Very easy to check...if the buckles are scrunched up...they have been deployed. I attached a picture of non-deployed seat belt (Deville). Any deployment event requires replacement of the SDM (pretensioners..side..frontal)

The SDM may have been replaced with a used one. You cannot do this due to the VIN being programmed into the SDM....and this can only be done one time.

"Class 2 Serial Data Communication allows control modules (i.e. the Powertrain Control Module (PCM), the Body Control Module (BCM), the Dash Integration Module (DIM), the Instrument Panel Cluster (IPC), the radio, the Heating, Ventilation and Air Conditioning (HVAC) Controller, and the Sensing and Diagnostic Module (SDM) to exchange information. This information may be operational information or identification information. Among the identification information exchanged and compared within these modules is the Vehicle Identification Number (VIN). Typically the one module, the master module, broadcasts the VIN and all the other modules compare the VIN stored within itself. When the broadcast VIN does not match the VIN stored within the SDM, the following actions occur:

• DTC B1001 Option Configuration Error is set and deployment of the airbags is inhibited.

• DTC B1271 or a DTC B1780 Theft Locked.

The VIN information is also used by the radio. When the VIN does not match the VIN stored within the radio, DTC B1271 or DTC B1780 is set and the radio is inoperative.

Additionally, the master module will compare the SDM's part number (last four digits) to determine if the correct SDM is installed in the vehicle. If the SDM is the wrong part, a B1001 will also set.

This situation may occur when a vehicle is being repaired. When a PCM or a body control type module is replaced, the VIN information must be programmed into the replaced (new) control module. A module which has had VIN information entered into it (for example, one taken from another vehicle) cannot be reprogrammed. VIN information can only be entered into new modules. The ignition must be ON in order to program the control module. Since the VIN information is broadcast when the ignition goes to ON from any other ignition switch position, DTCs may be set in the SDM and/or the radio. Therefore, always follow the specified control module replacement procedures."

[Robert Parrillo]

Sounds to me like you have a leak in the rear of the car. Check out if it's wet under rear seat and or trunk at the seat. I'll bet rain water is getting in. 150% sure of it.

[Chris Johnson]

I'm having a problem with my 2000 seville sts.. Replace battery and alternator, but the battery dies or seems to die when I shut it off.. I can charge it fires right up, drive for a few minutes turn it off and its dead...doest show electrical service warning ⚠ like it did when I changed the alternator, when I turn the key dash light go black

[Chris Johnson]

2000 seville sts, changed alternator and battery, turn car off it went start back, dash goes black when I turn the key

[Cadillac Jim]

The first thing to do is to run the OBD codes and post them here.

But you can start by cleaning the battery cables and making sure that the two grounds of the black cable are clean and tight.