Electronic Stability Control (ESC) Indicator

WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

The ESC indicator gives an indication to the vehicle operator when a problem has been detected in the Electronic Stability Control or when the system has been activated. The indicator is controlled by a transistor on the Instrument Panel Cluster (IPC) circuit board based upon IPC programming and electronic messages received by the IPC from the Controller Antilock Brake (CAB), and the Body Control Module (BCM) over the Controller Area Network (CAN) data bus.

The ESC indicator Light Emitting Diode (LED) is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is provided a path to ground by the IPC transistor. Each time the ignition switch is turned to the ON position the ESC indicator is illuminated for about four seconds as a bulb test. The IPC will turn ON the ESC indicator for the following reasons:

ESC Indicator Lamp-On Message - Each time the cluster receives an electronic ESC indicator lamp-ON message from the CAB or the BCM, the ESC indicator will be illuminated. The indicator remains illuminated until the IPC receives a lamp-OFF message from the CAB or BCM, or until the ignition switch is turned to the OFF position, whichever occurs first.

The CAB and BCM continually monitor the ESC system circuits and sensors to decide whether the system is in good operating condition and the proper outputs to the components of the system. The CAB or BCM then sends the proper lamp-ON or lamp-OFF message to the IPC.