B123D — dynamic stability control button

Causes

• Faulty DSC/traction control button (mechanical or internal electrical failure)
• Poor connector connection or corroded/pinched wiring in the button circuit
• Open/short to power or ground in the switch feed or return
• Loss of or errors on the CAN/vehicle network carrying the button status
• Faulty Body Control Module (BCM) or ABS/ESC control module not processing the input
• Software or calibration error requiring reprogramming or module initialization

Symptoms

• DSC/traction control mode selector does not change modes or does not respond
• DSC/TC warning or lamp illuminated on dash
• Inability to enable/disable traction control via the button
• Associated ABS/ESC warnings or degraded functionality messages
• Possible stored additional DTCs in ABS/ESC or body control modules

What to check

• Use a diagnostic scanner to read freeze frame and related DTCs from BCM, ABS/ESC modules and check live data for the button status
• Visually inspect the DSC button assembly and its connector for damage, corrosion, and secure fit
• Inspect wiring harness for chafing, pinching, or repairs in the area between the button and the BCM or central junction
• Check relevant fuses and permanent/ignition power and ground circuits for the switch and controlling modules
• Check for CAN bus faults and other module communication errors using a capable scan tool

Signal parameters

• Button output typically seen as a logic state change (active/inactive) in module live data or as a CAN message bit toggling when pressed
• Expected electrical behaviour: low/high logic level (near 0 V vs near battery voltage) or open/closed contact — compare to factory data for exact values
• CAN: periodic message containing DSC button state; message should change when button is operated and have correct node IDs and no CRC/errors
• Resistance/continuity: manual switch may show near zero ohms when closed and open when released (confirm with service info)

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