B11BA Code: Meaning, Causes, and Symptoms | OBD2 Codes

B11BA – Steering Wheel Audio Switch Pack


B11BA Possible Symptoms


Engine Light ON (or Service Engine Soon Warning Light)


B11BA Possible Causes


Faulty Steering Wheel Audio Switch Pack,Steering Wheel Audio Switch Pack harness is open or shorted,Steering Wheel Audio Switch Pack circuit poor electrical connection,Faulty Audio Control Module (ACM) or Accessory Protocol Interface Module (APIM)


B11BA Description


Voltage is sent from the Audio Control Module (ACM) or Accessory Protocol Interface Module (APIM) to the steering wheel controls, and the same module grounds the return circuit. The VOL-, VOL+, SEEK- and SEEK+ switches share signal and return circuits, while the VOICE, MEDIA, PHONE and OK switches share separate signal and return circuits. For all configurations, when a switch is pressed, the voltage is routed through a specific resistor value for each function. The ACM (or APIM) then uses the reference voltage to determine which control input function has been selected. The OBDII code is set by the ACM when the reference voltage to the steering wheel controls is out-of-range. This can be caused by a number of different failures on the steering wheel controls circuit except for a stuck switch or a short to ground in the signal return circuit.