Vibrations or Beeps? — Active Safety Seat Operation

The Active Safety Seat available on many 2013-2018 GM models provides a vibration, or haptic warning, in the driver’s seat cushion to alert the driver of the direction of potential hazards. It’s part of a growing collection of safety systems included on new GM models and works in conjunction with features such as Forward Collision Alert, Lane Departure Warning, Front Pedestrian Braking, Parking Assist, Rear Cross Traffic Alert and others.

 

The Active Safety Seat uses two haptic signal motors in the left and right side of the driver’s seat cushion to provide the vibration warning. Depending on the alert, either the left, right, or both motors will activate. (Fig. 12)

 

Fig. 12

 

The K40D Seat Memory Control Module (MSM) receives serial data messages from other modules and provides a voltage output to turn on the haptic signal motors. The Seat Memory Control Module will pulse the left, right, or both motors the number of pulses requested over serial data. The module monitors the circuits for open, short to ground, and short to voltage conditions and will set DTCs if a problem is detected.

 

Haptic Warnings

 

Depending on how a vehicle is equipped, it may have a number of active safety systems. Here’s the typical operation of the Active Safety Seat with some of the most popular safety systems:

 

  • Front and Rear Parking Assist – When an object is first detected, both motors will pulse twice. If a potential collision is detected, both motors will pulse five times.
  • Lane Departure Warning – When the vehicle crosses a lane marking, either the left or right motor will pulse three times, depending on the departure direction. The Lane Keep Assist feature, which provides steering input, does not activate the Active Safety Seat.
  • Forward Collision Alert – Both motors will pulse five times.
  • Rear Cross Traffic Alert – When backing up, if rear cross traffic is detected, either the left or right motor will pulse three times, depending on which side the traffic is detected.

 

Alert Type Setting

 

If there is a concern about the operation of the Active Safety Seat in various driving situations, the Alert Type setting should be checked in the vehicle personalization menu to ensure the seat haptic warning is turned on.

 

The driver can select to receive the Active Safety Seat haptic warning or audible alerts (beeps). The setting to turn the Active Safety Seat on/off can be found in the vehicle personalization menus using the infotainment controls. Go to Settings > Vehicle > Collision/Detection Systems > Alert Type. (Fig. 13)

 

Fig. 13

 

TIP: Check the Alert Type setting in the service lane with the customer before the vehicle is left with the service department.

 

System Diagnosis

 

Always check for any set DTCs (B172E – Driver Seat Cushion Left Rear Haptic Alert Motor Control Circuit;  B172F – Driver Seat Cushion Right Rear Haptic Alert Motor Control Circuit) when diagnosing the Active Safety Seat. Do not replace the haptic signal motors (Fig. 14) unless diagnosis clearly points toward the motors as the cause of the condition. If there aren’t any DTCs set, first check the Alert Type setting in the vehicle personalization menus.

 

Fig. 14

 

If the haptic signal motors are to be replaced, remove the driver’s seat cushion cover and pad to access the motors and electrical connectors.

 

Once the haptic signal motors are replaced, the Memory Seat Control Module should be cleared of any DTCs. It is not required to reflash or set up the module.

 

– Thanks to Daryl Funds

 

 

GR8 Battery Tester/Charger Software Update
Volt and ELR with No Charge Condition Due to Loss of High Voltage Isolation

Comments are closed.