Retained Accessory Power System Cadillac CTS I

Scheme 3

Diagnostic Starting Point - Retained Accessory Power

Begin the system diagnosis with the Diagnostic System Check - Retained Accessory Power . The diagnostic system check will provide the following information

1. The identification of the control modules which command the system
2. The ability of the control modules to communicate through the serial data circuit
3. The identification of any stored diagnostic trouble codes DTCs and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 2: 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.
2. 3: This step tests for valid system power moding in all ignition switch positions.
3. 5: 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.
4. 8: A fault with a door switch will prevent the RAP system from functioning properly.

Diagnostic System Check - Retained Accessory Power

Scan Tool Output Controls

Rear Integration Module (RIM) Scan Tool Output Controls

Scan Tool Data List

Dash Integration Module (DIM) Scan Tool Data List

Rear Integration Module (RIM) Scan Tool Data List

Symptoms - Retained Accessory Power

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the RAP feature. Refer to «Checking Aftermarket Accessories»(/cadillac/cts/i-2002-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__checking-aftermarket-accessories) in Wiring Systems.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Retained Accessory Power (RAP) On After Timeout»(/cadillac/cts/i-2002-2007/remont/accessories-control-systems/#retained-accessory-power-system__retained-accessory-power-rap-on-after)
2. «Retained Accessory Power (RAP) Inoperative»(/cadillac/cts/i-2002-2007/remont/accessories-control-systems/#retained-accessory-power-system__retained-accessory-power-rap-inoperative)

Retained Accessory Power (RAP) On After Timeout

Retained Accessory Power (RAP) On After Timeout

Retained Accessory Power (RAP) Inoperative

Retained Accessory Power (RAP) Inoperative

Serial Data Control of Retained Accessory Power (RAP)

Retained accessory power (RAP) is a vehicle power mode that permits the operation of selected customer convenience items after the ignition switch is turned OFF. These selected items will remain in operation until a passenger compartment door is opened or until the RAP function timer reaches its shut-off limit.

The modules listed below all receive a RAP message from the dash integration module (DIM) over the serial data circuits. The DIM monitors the ignition switch position, battery condition and passenger compartment door status to determine whether RAP should be initiated. The DIM then sends a message to the listed modules telling them that they are in RAP power mode. The modules then support the operation of the systems under their control as required by their RAP power mode strategy.

RAP will end when one of the following conditions are met

1. The DIM receives an input as a serial data message from any door module indicating the opening of a passenger compartment door.
2. The DIM receives a message from its internal timer indicating the end of the RAP period after 10 minutes.
3. The DIM detects a decrease in battery capacity below a prescribed limit.
4. The transition from OFF to RUN/ON or ACC of the ignition switch.

The DIM module then sends a serial data message to the listed modules ending the RAP function.

The modules receiving serial data messages for RAP functions are

1. The driver door module (DDM)
2. The front passenger door module (FPDM)
3. The left rear door module (LRDM)
4. The radio
5. The rear integration module (RIM)
6. The right rear door module (RRDM)
7. The TV antenna module
8. The vehicle communication Interface module (VCIM)

Relay Control of Retained Accessory Power (RAP)

When the rear integration module (RIM) is in the RAP function as described above, it actuates the RAP relay. This provides power during the RAP period for the sunroof control module w/CF5.

The RIM deactivates the RAP relay to end the RAP function when it ends the RAP function as outlined in the previous text.

See also:
• Scan Tool Does Not Power Up
• Power Mode Mismatch
• Diagnostic Trouble Code (DTC) List
• Diagnostic Trouble Code (DTC) List
• Interior Lighting Systems Description and Operation
• Diagnostic System Check - Lighting Systems
• Checking Aftermarket Accessories
• Testing for Intermittent Conditions and Poor Connections
• Master Electrical Component List
• Circuit Testing
• Wiring Repairs
• Connector Repairs
• Diagnostic System Check - Retained Accessory Power
• Symptoms - Retained Accessory Power
• Retained Accessory Power (RAP) On After Timeout
• Retained Accessory Power (RAP) Inoperative