DTC 72, LCD Dimming Output Circuit Open Or Shorted To Ground: Notes

CCM supplies ground for LCD dimming output circuit in the form of a Pulse Width Modulated (PWM) output through LCD dim control circuit to back lighting on radio control head and heater/air conditioning control head (if equipped with electronic heating/air conditioning). Power is supplied to LCD dim control circuit internally through radio control head and heater/air conditioning control head (if equipped with electronic heating/air conditioning).

DTC 72 will set when:

• Ignition 3 is on.
• Headlights and parking lights are on.
• PWM dimming control is not set for zero or 100 percent.
• No transition is captured over a specific time span at CCM terminal C2.
• PWM feedback shows a high logic state over the complete capture time.
• If an after market radio is installed and original radio control head dimming control lines have been left open, DTC 72 may set.

When DTC 72 is set, SYS will flash.

DTC 72 will clear when:

• Ignition 3 is off.
• Headlights and parking lights are off.
• PWM dimming control is set for zero or 100 percent.
• A transition is captured over a specific time span at CCM terminal C2.
• PWM feedback does not show a high logic state over the complete capture time.