5.3.7 PEPS Communication

The PEPS communication functionality can be tested using the CARS PC application running on the host PC as follows:

  1. If not done already, follow the procedure detailed in CARS Kit PC Evaluation Utility.
  2. If not done already, follow the calibration procedure detailed in Fob Calibration Process .
  3. Position the fob at the desired distance from the LF antenna module or X-10013-002 antenna that is used for the fob’s in/out threshold.
  4. Navigate to View > PEPS Messaging to open the PEPS Message Status window (see Figure 5-7).
  5. Select the Unilateral Authentication radio option, click the Unlock button and, after the authentication sequence completes, note the value of the number in the “Distance Scale (RSSI)” field of the PEPS Message Status window. Enter this value in the “In/Out Threshold” field of the System Configuration window (see Figure 5-18).
  6. Move the fob closer to the LF antenna module or X-10013-002 antenna.
  7. Select the Unilateral Authentication radio option, then click the Unlock button within the PEPS Message Status window to execute the unilateral authentication sequence.
    Note: The “LF Encrypted Challenge” field is not populated as this data is not transmitted to the fob.
    For example, the results of a PEPS unilateral authentication sequence display (see the following figure). With the “In/Out Threshold (RSSI)” as 400.0 and the measured value “Distance Scale (RSSI)” as 451.9, the fob is identified as Inside the vehicle and is highlighted in blue due to the distance scale value being greater than the threshold value.
    Figure 5-19. PEPS Unilateral Authentication with Inside Localization
  8. Move the fob further away from the LF antenna module or X-10013-002 antenna, beyond the location used in step 3 but still within the PEPS operating range.
  9. Select the Bilateral Authentication radio button, then click the Unlock button within the PEPS Message Status window to execute the bilateral authentication sequence. Confirm that the “LF Encrypted Challenge” field is now populated.
    For example, the results of a PEPS bilateral authentication sequence display (see the following figure). With the “In/Out Threshold (RSSI)” as 400.0 and the measured value “Distance Scale (RSSI)” as 300.3, the fob is identified as Outside the vehicle and is highlighted in pink due to the distance scale value being less than the threshold value.
    Figure 5-20. PEPS Bilateral Authentication with Outside Localization
Note:
  • Use either the Unilateral Authentication or Bilateral Authentication options for inside or outside localization.
  • Each time any of the PEPS command buttons (Start/Stop, Unlock or Lock) are clicked, a new PEPS wake-up signal is generated. Once the fob receives the wake-up signal, the LED on the fob blinks and the PEPS Message Status window information is updated.
  • A continuous polling sequence can be achieved by selecting the “Polling” check box in the “PEPS Features” section of the System Configuration window. This polling feature can be used to dynamically determine the PEPS fob area coverage in real-time with the PEPS results displaying in the PEPS Message Status window.