What is the codes PCM, SDM, PZM and IRC mean?

You probably fried a control module , It doesn't take long ! Would need to hook up a professional scan tool that can communicate with all the modules . Check codes the BCM - body control system . Without testing we would only be guessing . Your best bet would be to take it to a qualified repair shop . Your looking at major bucks . I have worked at cadillac an have see this before ! Control Module Diagnostics with John Anello
Sorry but there is no way you'll be able to fix this !
This vehicle has electronic components which the service technician controls in order to provide valuable self-diagnostic information. These components are part of an electrical network that controls various engine subsystems and various body subsystems. A description of each of these subsystems is in the appropriate subsection of this service manual. These major components that compromise the computer system monitor the system sensors and the system switches. These components are the following:
• The powertrain control module (PCM)
• The instrument cluster
• The air controller module (ACM)
• The sensing and diagnostic module (SDM)
• The electronic brake and traction control module (EBTCM)
• The continuously variable road sensing suspension module (CVRSS)
• The body control module (PZM)
• The integrated radio controller (IRC)
• The remote function actuator (RFA)
• The climate control panel (CCP)
• The cellular telephone (PHN)
System Functions
The body control module (PZM) performs the following functions:
• HVAC afterblow control
• Battery guard
• Door lock and unlock
• Fuel level
• Retained accessory power (RAP)
• Theft deterrent
• Exterior lighting control
• Interior lighting control
• Trunk release
• Time of day for the radio display
• Rear defogger
• Fuel door release
• Vehicle personalization
For more information about these functions refer to the appropriate sections.

TDM ? explain what you think this is ? If you are referring to a module here is a list of the ones on your caddy.
The control modules on the class 2 data line can include the following modules:
?€¢
The body control module (PZM)

?€¢
The cellular telephone module (PHN)

?€¢
The climate control panel (CCP)

?€¢
The continuously variable road sensing suspension (CVRSS) module (RSS) (w/F45)

?€¢
The electronic brake and traction control module (EBTCM) (ABS)

?€¢
The heater and A/C programmer (HCM)

?€¢
The inflatable restraint sensing and diagnostic module (SDM)

?€¢
The instrument cluster (IPC)

?€¢
The memory mirror module (MMM) (w/A45)

?€¢
The memory seat module (MSM) (w/A45)

?€¢
The powertrain control module (PCM)

?€¢
The radio (IRC)

?€¢
The radio interface module (RIM) (w/UQ4)

?€¢
The remote function actuator (RFA) module

P0603 - GM Type Powertrain - Computer and Auxiliary Outputs - ISO/SAE Controlled Description Control Module Long Term Memory Reset Conditions
Cause DTC P0604 not set, key on, then the PCM determined that its calculated checksum that did not match a previous checksum • Refer to code repair chart for instructions on how to replace a PCM and how to reprogram the replacement
or you can ask the 24 hrs live technical support obd2 bmw icom, they will like to help you, good luck

Do you know what U code's are for ? How did you pull this code ? There is no U0155 , U code's start at
Diagnostic Trouble Code (DTC) List
DTC
Diagnostic Procedure
Modules
U1000
DTC U1000 and U1255
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, Remote Playback Device CD Changer, RCDLR, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1016
DTC U1001-U1254
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC , IPM, LMDM, LRDM, MSM, Radio, RCDLR, RIM, RRDM, RMDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1040
DTC U1001-U1254
IPC, PCM, SDM
U1056
DTC U1001-U1254
EBCM, PCM
U1064
DTC U1001-U1254
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, RCDLR, Remote Playback Device CD Changer, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1065
DTC U1001-U1254
DDM, DIM, ESC, FPDM, IPC, LMDM, LRDM, VCIM, HVAC Control Module - Auxiliary, PCM, Radio, RIM, RMDM, RRDM, VCIM
U1066
DTC U1001-U1254
DDM, FPDM, IPC, IPM, PCM
U1088
DTC U1001-U1254
IPC
U1096
DTC U1001-U1254
PCM, SDM
U1128
DTC U1001-U1254
Audio Amplifier, Cellular Telephone Module, Digital Radio Receiver, Remote Playback Device CD Changer, VCIM
U1129
DTC U1001-U1254
Radio
U1130
DTC U1001-U1254
Radio
U1137
DTC U1001-U1254
Radio
U1144
DTC U1001-U1254
IPC, Radio
U1151
DTC U1001-U1254
Radio
U1160
DTC U1001-U1254
IPC, RIM
U1161
DTC U1001-U1254
IPC, RIM
U1162
DTC U1001-U1254
IPC, RIM
U1163
DTC U1001-U1254
IPC, RIM
U1164
DTC U1001-U1254
DDM, Digital Radio Receiver, DIM, FPDM, IPC, LRDM, MSM, VCIM, Radio, RIM, RRDM, Steering Column Module
U1165
DTC U1001-U1254
DDM, FPDM, LRDM, RRDM
U1176
DTC U1001-U1254
IPC
U1192
DTC U1001-U1254
IPC, PCM
U1255
DTC U1000 and U1255
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, Remote Playback Device CD Changer, RCDLR, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1300
DTC U1300, U1301, or U1305
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, Remote Playback Device CD Changer, RCDLR, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1301
DTC U1300, U1301, or U1305
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, Remote Playback Device CD Changer, RCDLR, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car
U1305
DTC U1300, U1301, or U1305
Audio Amplifier, Cellular Telephone Module, DDM, DDSA, Digital Radio Receiver, DIM, EBCM, ESC, FPDM, HVAC Control Module - Auxiliary, IPC, IPM, LMDM, LRDM, MSM, PCM, Radio, Remote Playback Device CD Changer, RCDLR, RIM, RMDM, RRDM, SDM, Steering Column Module, Theft Deterrent Control Module, VCIM, Window Switch - Front Passenger w/armored car

The data link connector (DLC) allows a scan tool to communicate with the class 2 serial data line. The serial data line is the means by which the microprocessor-controlled modules in the vehicle communicate with each other. Once the scan tool is connected to the class 2 serial data line through the DLC, the scan tool can be used to monitor each module for diagnostic purposes and to check for diagnostic trouble codes (DTCs). Class 2 serial data is transmitted on a single wire at an average of 10.4 kbps. This value is an average; class 2 uses a variable pulse width modulation to carry data and depending on the message it may operate faster or slower. The bus will float at a nominal 7 volts during normal operation. Each module can pull this lower during the transmission. The bus is not at battery positive voltage or ground potential during normal operation. When the ignition switch is in RUN, each module communicating on the class 2 serial data line sends a state of health (SOH) message every 2 seconds to ensure that the module is operating properly. When a module stops communicating on the class 2 serial data line, for example, if the module loses power or ground, the SOH message it normally sends on the data line every 2 seconds disappears. Other modules on the class 2 serial data line, which expect to receive that SOH message, detect its absence; those modules in turn set an internal DTC associated with the loss of SOH of the non-communicating module. The DTC is unique to the module which is not communicating; for example, when the inflatable restraint sensing and diagnostic module (SDM) SOH message disappears, several modules set DTC U1088. Note that a loss of serial data DTC does not normally represent a failure of the module that set it.

Your best bet ,take it to a qualified repair shop.

This code pertains to communication from one computer to the next,they all are on a communication circuit (class II) & you have a short to ground somewhere.If a scan tool is able to communicate with the computer(and it is since you got a failure code) this code is intermitten.Get a good volt meter or scan tool & start at the ALDL (where the scanner plugs in).Inspect & check wiring as you keep an eye on the scanner or meter.

DTC Parameters
DTC U1300 will set if the EBTCM, PCM, or SDM detected the Class II circuit in the low state for too long. (Class II circuit shorted to ground) when:
• Condition exists for longer than 4 seconds for EBTCM, 2 seconds for PCM and SDM.
• Ignition is On.

DTC U1300 diagnostic runs continuously with ignition On.

DTC U1300 is a type C DTC.
Diagnostic Aids
If the scan tool can communicate with the EBTCM, PCM or SDM, then the Class II link is not currently shorted to ground.

Inspect the wiring harness for signs of chafing or broken insulation.

Important: The controller name won't be displayed until the scan tool initially received the correct controller ID over the link upon ignition On.

Important: The BCM CANNOT set U1300.

To locate an intermittent problem, use the scan tool to monitor any of the controllers on the Class II link located under DIAGNOSTIC CIRCUIT CHECK - - - CLASS II MESSAGE MONITOR with ignition On, engine Off. INACTIVE will be displayed on all controllers if the link is shorted to ground.


Hope this helps (remember to rate this answer).

this site has alot of info:

http://myweb.accessus.net/~090/dtcobd1.html

Hope this is what you need!!!

ABS (Antilock Brake System)
AMP (Amplifier)
DDM (Door Driver Module)
DIM (Dash Integration Module)
IPC (Instrument Panel Cluster)
IPM (Instrument Panel Module)
IRC (Integrated Radio Module)
PCM (Powertrain Control Module)
RFA (Remote Function Actuation)
RIM (Rear Integration Module)
SDM (Sensing and Diagnostic Module) Includes airbag crash data. Under RF seat
VTD (Vehicle Theft Deterrent)
MSM (Memory Seat Module)
TTM (Tilt/Telescoping Module)
RSS (Road Sensing Suspension)
____________________________________________________________

How To Pull Codes To check for Diagnostic Trouble Codes stored in the computer, turn the ignition on, then hold down the OFF and WARMER (for digital dash) or OFF and passenger-WARMER buttons (for analog dash) or OFF and "Info ^" buttons (if you have temperature dials) until all of the dash lights come on. The digital display will then show any codes stored. Be prepared to write them down. When it's done, you will probably see "PCM?" At that point, press the OFF button 3 or 4 times until the dash goes back to normal, or just turn off the ignition.

HOW TO "ENTER" DIAGNOSTIC MODE OBDII

To enter diagnostic mode, proceed as follows:

1. Turn ignition "ON." Engine can be either OFF or RUNNING.

For cars equipped with the Digital Instrument Panel Display (Digital IPC):
2. Simultaneously press the "OFF and "WARMER" (red) buttons on climate control center (CCC) until all display segments (IPC and CCP) are illuminated

For cars equipped with the Analog Instrument Panel Display (Analog IPC):
3. Simultaneously press on the Climate Control Panel (CCP) the "OFF" and "PASS WARMER" (up arrow) buttons.

After the segment display test, the driver message center displays all set DTC, current and history, in the following order:

1. PCM DTC
2. IPC DTC
3. ACM DTC
4. SDM DTC
5. TCS DTC
6. PZM DTC
7. IRC DTC
8. RFA DTC
9. CCP DTC
10. MSM DTC
11. MMM DTC
12. PHN DTC

The RSS, CCP, MSM, MMM and PHN DTC appear only on vehicles equipped with these options. Press the FAN DOWN button in order to bypass the DTC display.

On the OBD II cars, the prefixes you'll see are: "IP" for the IPC instrument panel; "AC" for air conditioning module; "TC" for traction control; "RS" for the road suspension system; "SD" for the air bags; "PZ" for the body control module; "CC" for the cell phone; "RF" for the integrated radio system.



HOW TO "EXIT" DIAGNOSTIC MODE

To exit the diagnostic mode anytime during the test, depress the "ECON" or "DEFOG" button, or turn the ignition switch "OFF." .

You don't need a scan tool for these cars,as it is all built in.

Go to the following website for a list of trouble codes.

http://myweb.accessus.net/~090/dtcobd2.html

Add a comment to your post if you require any further assistance.

Hope this helps.

On these cars no scan tool is needed, you can run a self diagnostic check from the dashboard as it is all built in.

To enter diagnostic mode, proceed as follows:

1. Turn ignition "ON." Engine can be either OFF or RUNNING. For cars equipped with the Digital Instrument Panel Display (Digital IPC):
   
2. Simultaneously press the "OFF and "WARMER" (red) buttons on climate control center (CCC) until all display segments (IPC and CCP) are illuminated For cars equipped with the Analog Instrument Panel Display (Analog IPC):
   
3. Simultaneously press on the Climate Control Panel (CCP) the "OFF" and "PASS WARMER" (up arrow) buttons.

After the segment display test, the driver message center displays all set trouble codes, current and history, in the following order:

1. PCM DTC
2. IPC DTC
3. ACM DTC
4. SDM DTC
5. TCS DTC
6. PZM DTC
7. IRC DTC
8. RFA DTC
9. CCP DTC
10. MSM DTC
11. MMM DTC
12. PHN DTC
The RSS, CCP, MSM, MMM and PHN DTC appear only on vehicles equipped with these options. Press the FAN DOWN button in order to bypass the DTC display.

On the OBD II cars, the prefixes you'll see are: "IP" for the IPC instrument panel; "AC" for air conditioning module; "TC" for traction control; "RS" for the road suspension system; "SD" for the air bags; "PZ" for the body control module; "CC" for the cell phone; "RF" for the integrated radio system.

To exit the diagnostic mode anytime during the test, depress the "ECON" or "DEFOG" button, or turn the ignition switch "OFF."

Write down the list of trouble codes and report back here.

Run a diagnostic check to extract the trouble codes,then post the results back here.

To enter diagnostic mode, proceed as follows:

1. Turn ignition "ON." Engine can be either OFF or RUNNING. For cars equipped with the Digital Instrument Panel Display (Digital IPC):
   
2. Simultaneously press the "OFF and "WARMER" (red) buttons on climate control center (CCC) until all display segments (IPC and CCP) are illuminated For cars equipped with the Analog Instrument Panel Display (Analog IPC):
   
3. Simultaneously press on the Climate Control Panel (CCP) the "OFF" and "PASS WARMER" (up arrow) buttons.

After the segment display test, the driver message center displays all set trouble codes, current and history, in the following order:

1. PCM DTC
2. IPC DTC
3. ACM DTC
4. SDM DTC
5. TCS DTC
6. PZM DTC
7. IRC DTC
8. RFA DTC
9. CCP DTC
10. MSM DTC
11. MMM DTC
12. PHN DTC
The RSS, CCP, MSM, MMM and PHN DTC appear only on vehicles equipped with these options. Press the FAN DOWN button in order to bypass the DTC display.

On the OBD II cars, the prefixes you'll see are: "IP" for the IPC instrument panel; "AC" for air conditioning module; "TC" for traction control; "RS" for the road suspension system; "SD" for the air bags; "PZ" for the body control module; "CC" for the cell phone; "RF" for the integrated radio system.

To exit the diagnostic mode anytime during the test, depress the "ECON" or "DEFOG" button, or turn the ignition switch "OFF."

Write down the list of codes and report back here.

First off you need to know how these thing's work ,computer controlled .

Trunk Release Function
When the PZM receives a serial data message for the activation of the trunk release solenoid from the instrument cluster or from the RFA, the PZM energizes the trunk release relay under the following conditions:
• The transmission is in PARK
• The valet lockout switch is not activated.

Components
This vehicle has electronic components which the service technician controls in order to provide valuable self-diagnostic information. These components are part of an electrical network that controls various engine subsystems and various body subsystems. A description of each of these subsystems is in the appropriate subsection of this service manual. These major components that compromise the computer system monitor the system sensors and the system switches. These components are the following:
• The powertrain control module (PCM)
• The instrument cluster
• The air controller module (ACM)
• The sensing and diagnostic module (SDM)
• The electronic brake and traction control module (EBTCM)
• The continuously variable road sensing suspension module (CVRSS)
• The body control module (PZM)
• The integrated radio controller (IRC)
• The remote function actuator (RFA)
• The climate control panel (CCP)
• The cellular telephone (PHN)
System Functions
The body control module (PZM) performs the following functions:
• HVAC afterblow control
• Battery guard
• Door lock and unlock
• Fuel level
• Retained accessory power (RAP)
• Theft deterrent
• Exterior lighting control
• Interior lighting control
• Trunk release
• Time of day for the radio display
• Rear defogger
• Fuel door release
• Vehicle personalization
For more information about these functions refer to the appropriate sections.

Your probably have a lose connection somewhere , ground for the BCM or instrument cluster . Behind the dash or instrument cluster ! or other places . G-400 ,G205

The instrument cluster supplies the turn on signal for the alternator

DTC B1910 Generator L-Terminal Open Circuit
DTC B1911 Generator L-Terminal Problem
DTC B1981 Battery Voltage Low
The generator provides the voltage to operate the vehicle's electrical system and to charge the battery through CKT 1 (RED). When the ignition switch is placed in RUN, narrow width pulses on CKT 23 (GRY) are supplied by the powertrain control module (PCM) to the rotor, creating a weak magnetic field. When the engine is started, the regulator senses the generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This regulates the generator output voltage for proper battery charging and electrical system operation.
The PCM turns on the VOLT indicator via Class 2 serial data line CKTs 1807 (PPL) whenever undervoltage, overvoltage, or a stopped generator is detected on CKT 225 (RED).

When the ignition switch is placed in the RUN position, voltage is supplied to generator terminal L by the instrument cluster, turning on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This operation regulates the generator output voltage for proper battery charging and electrical system operation. The generator F terminal is connected internally to the voltage regulator and externally to the PCM. The PCM monitors the field voltage on the generator F terminal.

It's more then likely just a lose connection somewhere . Could take half your vehicle apart to find it .

My first place to look would be here , G400
In the left rear of the passenger compartment, under the rear seat
BCM ground .