2003 Chevrolet Impala LSFACTORY OEM SERVICE PROCEDURE

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. 3:  This step checks for a short to voltage.
DTC B1003

Step Action Yes No
Schematic Reference:  Keyless Entry Schematics  
1 Did you perform the Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Remote Keyless Entry 
2
  1. Turn OFF the ignition.
  2. Disconnect the remote control door lock receiver (RCDLR).
  3. Connect a test lamp from the keyless entry serial data circuit to a good ground.
  4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 3  Go to Step 4 
3  Test the keyless entry serial data circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 5 
4 Inspect for poor connections at the harness connector of the RCDLR. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 6 
5 Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 7 
6
IMPORTANT: All transmitters which are to be recognized by the RCDLR must be programmed in a single programming sequence. If the system is placed in program mode it will erase all previously programmed transmitters upon the receipt of the programming signal from the first transmitter.
Replace the RCDLR. Refer to Remote Control Door Lock Receiver Replacement .Did you complete the replacement?		 Go to Step 8  -
7
IMPORTANT: Perform the BCM programming procedure when replacing the BCM.
Replace the BCM. Refer to Body Control Module Replacement in Body Control System.
Did you complete the replacement?		 Go to Step 8  -
8
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 Go to Step 2  System OK
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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