Circuit/System Testing

WARNING: This page is about a different car, the 2023 GMC Sierra 3500 HD and 2023 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Ignition ON.
Using the master code, verify the Front Side Door Access Control Transmitter is functioning by unlocking the vehicle.
- If the Front Side Door Access Control Transmitter LED light does not illuminate and the vehicle does not unlock
  Replace the Front Side Door Access Control Transmitter.
- Go to next step: If the Front Side Door Access Control Transmitter LED light does illuminate and the vehicle does not unlock
Verify the Front Side Door Access Control Transmitter is the correct part number and frequency for the vehicle.
- If the part number or frequency is incorrect for the vehicle
  Replace the Front Side Door Access Control Transmitter.
- If the part number and frequency are both correct
Use the EL-52545 to verify the Front Side Door Access Control Transmitter is emitting a signal strength of 20% or greater.
- If the Front Side Door Access Control Transmitter does not emit a signal of 20% or greater
  Replace the Front Side Door Access Control Transmitter.
- Go to next step: If the Front Side Door Access Control Transmitter does emit a signal of 20% or greater
All OK.