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Home >> Chevrolet >> 2021 >> Express 2500 LS, 2.8L Eng VIN 1 >> Repair and Diagnosis >> External Pages >> Different car >> Section 72 (Remote Functions) >> Diagnostic Information and Procedures >> Front Side Door Access Control Transmitter Malfunction >> Circuit/System Verification

Circuit/System Verification

WARNING: This page is about a different car, the 2022 GMC Savana 3500, 2022 GMC Savana 2500, 2022 Chevrolet Express 3500, and 2022 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.

In order to determine the best starting point to begin diagnosis first determine which features on the vehicle are functioning correctly or not. By performing a simple and quick check on the vehicle it can be determined if there is or isn't a fault in each feature. If any one part of the feature is faulty then the feature status is failed.

Match the status of all four features and go the suggested link to begin diagnosis.

Active Keyless Entry Verification

  1. Ignition off, stand approximately 10 meters (33 feet) from the vehicle.
  2. Verify that no other DTCs are set, as they could be the root cause of the issue.
    • Go to next step: If none of the DTCs are set 
  3. Verify the keyless entry transmitter locks and unlocks the vehicle.
    • Go to next step: If the vehicle locks and unlocks 
  4. Verify the Front Side Door Access Control Transmitter locks and unlocks the vehicle.
    • Go to next step: If the vehicle either does not lock or does not unlock 

      Go to next step: Refer to circuit system testing below.

    • Go to next step: If the vehicle locks and unlocks 
  5. All OK.
Keyless Entry Transmitter Status Front Side Door Access Control Transmitter Status Most Probable Diagnostic Starting Point
Passed Passed -
Passed Failed Front Side Door Access Control Transmitter
Failed Passed Keyless Entry Transmitter
Failed Failed Remote Control Door Lock Receiver