Turn Signal Indicators

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

The turn signal indicators give an indication to the vehicle operator that the turn signal (left or right indicator flashing) or hazard warning (both left and right indicators flashing) have been selected and are operating. These indicators are controlled by transistors on the IC cluster electronic circuit board based upon cluster programming and electronic messages received from the BCM over the CAN data bus.

Each turn signal indicator Light Emitting Diode (LED) unit is completely controlled by the IC logic circuit, and that logic will allow this indicator to operate whenever the IC receives a battery current input on the fused B(+) circuit. Therefore, each LED can be illuminated regardless of the ignition switch status. The LED only illuminates when it is provided a path to ground by the IC transistor. The IC will turn ON the turn signal indicators for the following reasons:

Turn Signal Indicator Lamp-On Message - Each time the IC receives an electronic right or left turn signal indicator lamp-On message from the BCM over the CAN data bus, the appropriate turn signal indicator will be flashed on and off. The BCM messages to the IC also control the flash rate of the turn signal indicators, as well as the click rate of an electromechanical relay soldered onto the IC electronic circuit board that emulates the sound emitted by a conventional turn signal flasher. The turn signal indicators continue to flash on and off until the IC receives a lamp-OFF message from the BCM, or until the ignition switch status transitions to OFF, whichever occurs first.
Hazard Warning Indicator Lamp-On Message - Each time the IC receives an electronic hazard warning indicator lamp-On message from the BCM over the CAN data bus, both turn signal indicators will be flashed on and off. The BCM messages to the IC also control the flash rate of the turn signal indicators, as well as the click rate of an electromechanical relay soldered onto the IC electronic circuit board that emulates the sound emitted by a conventional hazard warning flasher. The turn signal indicators continue to flash on and off until the IC receives a lamp-OFF message from the BCM.
Turn Signal-On Textual Warning Message - When the BCM detects that a turn signal has been active continuously for 1.6 kilometers (1 mile) with the vehicle speed greater than 22 kilometers-per-hour (15 miles-per hour) a TURN SIGNAL ON textual message and flashing right or left turn signal icon will appear within the IC electronic display unit and a chime tone will be sounded.
Lamp Out Mode - If the BCM detects an ineffective turn signal lamp or circuit, it increases the flash rate for the remaining operative turn signals and sends an electronic message to the IC. The IC then increases the flash rate of the turn signal indicators and the click rate of the electromechanical relay to provide an indication of the problem to the vehicle operator.

The IC continually monitors electronic messages from the BCM to determine the proper turn signal and hazard warning indicator operation.

For proper diagnosis of the turn signal and hazard warning system, the multi-function switch, the BCM, the IC, the CAN data bus or the electronic communication related to turn signal indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.