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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Impala 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Retained Accessory Power Malfunction

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

RAP Relay Coil Control

B1475, 1

1

2

--

Battery Positive Voltage

3

4

2

--

Accessory Voltage (Relay Output)

3

4

2

--

Ground (RAP Relay)

--

1

--

--

  1. All relay controlled RAP functions inoperative.
  2. Relay RAP remains on past the timer limit after key out and will not turn off when a vehicle door is opened.
  3. Partial relay controlled RAP functions inoperative with open fuse.
  4. Partial relay controlled RAP functions inoperative with fuse OK.

Circuit/System Description

The retained accessory power (RAP) system allows specific vehicle functions to operate after the ignition is turned OFF for a predetermined time. The RAP relay is located in the instrument panel (I/P) fuse block. The relay accessory voltage (output) feeds the RAP fuse and the PWR/WNDW circuit breaker within the I/P fuse block. Relay RAP is controlled by the BCM using inputs from the door ajar switches to determine control of the relay when the ignition is turned OFF. Radio RAP is controlled by a serial data message from the BCM using inputs from the driver door open switch. Refer to Retained Accessory Power (RAP) Description and Operation for more detail on subsystems using RAP.

Diagnostic Aids
    • The radio RAP function is a separate RAP function controlled by serial data and the specific module. These functions are not effected by the BCM RAP relay circuits.
    • A short to ground or open/high resistance in the RAP relay switched voltage circuits will cause only part of the RAP functions to be inoperative. Diagnose these symptoms within the respective system sections.
    • A short to voltage on the RAP relay control or switched voltage circuits would cause the RAP function to remain on past the designated time.
    • A stuck relay switch could cause a RAP always on, or a RAP inoperative condition.

Reference Information

Schematic Reference

    •  Power Distribution Schematics
    •  Power Moding Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Retained Accessory Power (RAP) Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for Scan Tool Information

Circuit/System Verification

Important: Battery voltage must remain above 9.6 V for RAP to operate properly.

Radio RAP

  1. With all passenger doors closed, observe the courtesy lamps while opening and closing the driver door. The courtesy lamps should illuminate when the door is opened and turn off approximately 30 seconds after closing the door.
    2. ⇒If the courtesy lamp operation is incorrect from the drivers door, refer to Courtesy Lamps Malfunction .
  2. If courtesy lamp operation is correct, and the radio is the only RAP concern, replace the radio.

Relay RAP

  1. Ignition ON, observe the appropriate scan tool parameters listed below while opening and closing each vehicle door. The reading should change between Door Closed/Door Ajar.

    2. Parameter

    • Driver Door Ajar Sw.
    • Left Rear Door Ajar Sw.
    • Passenger Door Ajar Sw.
    • Right Rear Door Ajar Sw.
    ⇒If any parameter does not change as specified, refer to Door Ajar Indicator Malfunction .
  2. Command the scan tool Accy/RAP Relay OFF. Attempt to operate any RAP relay controlled component within 5 seconds. The component should not operate.
  3. Command the scan tool Accy/RAP Relay ON. Attempt to operate any RAP relay controlled component within 5 seconds. The component should operate.
  4. Ignition ON, all doors closed. Observe the scan tool parameter Accy/RAP Relay Command. Ignition OFF, key removed, the reading should be ON for approximately 10 minutes then change to OFF.
    5. ⇒If the parameter does not respond as specified, replace the BCM.

Circuit/System Testing
  1. Ignition OFF, disconnect the RAP Relay.
  2. Test for less than 2 ohms of resistance between ground circuit terminal and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between relay coil control circuit terminal and ground.
  4. With the driver and passenger doors open, cycle the ignition key ON and OFF. The test lamp should turn ON and OFF when cycling the ignition switch.
    5. ⇒If the test lamp remains ON all the time, test the relay coil control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp remains OFF all the time, test the relay coil control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM.
  5. Connect a test lamp between the relay accessory voltage circuit terminal and ground. The test lamp should not illuminate.
    6. ⇒If the test lamp illuminates, test the accessory voltage circuit for a short to voltage.
  6. If all circuits test normal, test or replace the RAP relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the RAP relay.
  2. Test for 70-110 ohms of resistance between terminals 85 and 86.
    3. ⇒If the resistance is not within the specified range, replace the relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    ⇒If not the specified value, replace the relay.
  4. Install a 20 amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2.0 ohms of resistance between terminals 30 and 87.
    5. ⇒If greater than the specified range, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

    •  Relay Replacement
    •  Control Module References for module replacement, setup, and programming