U1714

CIRCUIT DESCRIPTION
Express Up operation of the front door power windows is monitored and controlled by the front door modules and the window sensors. Each front door window motor has a window sensor mounted to it. The driver door module (DDM) and the passenger door module (PDM) each supply battery positive voltage and ground to power their respective window sensors. The door modules and sensors communicate with each other via a window sensor high speed communications circuit, and a window sensor normal speed communications circuit. The window sensor detects differences in the window motors electrical pulses to determine if there is an obstruction to the travel of the window glass. The door modules use the information generated by the sensors to disable the Express Up movement of a window, or reverse the direction of travel, in the event that a passenger, or other obstacle, has become trapped in it.

The window sensor normal speed circuit is a unique two-way serial data communications link between the door module and the sensor. State-of-health messages, window switch command status, and the actual position of the window glass in relationship to the distance traveled by the window, are communicated via this circuit.

CONDITIONS FOR RUNNING THE DTC
The door modules must be powered and can not have B1327-Battery Voltage Low or B1328-Battery Voltage High set for this DTC to set.

CONDITIONS FOR SETTING THE DTC
The DTC will be set by the driver door module (DDM) when either the DDM, or the passenger door module (PDM) has detected any of the following conditions:
^ The door module cannot communicate with the sensor over the window sensor normal speed communications line.
^ The window sensor normal speed communications line is open.
^ The window sensor normal speed communications line is shorted to ground.
^ The window sensor normal speed communications line is shorted to battery.

If the failure has occurred to the passenger side window, the PDM relays the information to the DDM and the DDM then sets the DTC.

ACTION TAKEN WHEN THE DTC SETS
The DDM or the PDM will not allow the Express Up function for that window to operate. All other window functions for that window will still operate.

CONDITIONS FOR CLEARING THE DTC
The DDM will clear the current DTC when window sensor normal speed communications between the DDM and its sensor, or the PDM and its sensor, have returned to normal.

DIAGNOSTIC AIDS
When DTC U1714 or DTC U1716 are set, a failure of the window sensor normal speed communications circuit is the probable cause.

However, DTC U1714 or U1716 may also be set if the window sensor has lost power. This could be due to a failure of the sensor battery positive voltage circuit, or a failure of the sensor ground circuit.

TEST

Steps 1-12:

Steps 13-14: