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 front door module (PFDM) each supply battery voltage and ground to power their respective window sensors. The door modules and sensors communicate with each other via a power window high speed serial data circuit, and a power window low speed serial data 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 power window low speed serial data circuit is a unique 2-way serial data communications link between the door module and the sensor. State-of-health messages, position of the window glass in relationship to the distance traveled by the window, and direction in which the window is moving are communicated via this circuit.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC U1714 Loss of Left Front Door Module to Window Motor Normal Speed Communication |
| • | DTC U1716 Loss of Right Front Door Module to Window Motor Normal Speed Communication |
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 DDM, or by the PFDM, when any of the following conditions has occurred:
| • | The door module cannot communicate with the sensor over the power window low speed serial data line. |
| • | The power window low speed serial data line is open. |
| • | The power window low speed serial data line is shorted to ground. |
| • | The power window low speed serial data line is shorted to battery. |
| • | The window sensor battery positive voltage circuit has failed. |
| • | The window sensor low reference circuit has failed. |
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 or the PFDM will clear the current DTC when power window low speed serial data communications between the sensor and associated door module, has returned to normal.
Diagnostic Aids
When DTC U1714 is set, a failure of the power window low speed serial data circuit is the probable cause. However, DTC U1714 may also be set if the window sensor has lost power, a condition that may be caused by a failure of the sensor battery voltage circuit, or a failure of the sensor low reference circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Power Window Schematics | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the voltage measure within the specified value? | 9.5-16.0 V | Go to Step 4 | Go to Step 3 |
3 | Measure the voltage between the sensor battery positive voltage circuit of the harness connector and a good ground. Does the voltage measure within the specified value? | 9.5-16.0 V | Go to Step 9 | Go to Step 8 |
4 | Measure the voltage between the power window low speed serial data circuit of the harness connector and a good ground. Does the voltage measure within the specified value? | 6.0-9.5 V | Go to Step 11 | Go to Step 5 |
5 | Was the voltage measured in step 4 greater than the specified value? | 6.0-9.5 V | Go to Step 7 | Go to Step 6 |
6 | Test the power window low speed serial data circuit of the window sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
7 | Test the power window low speed serial data circuit of the window sensor for a short to battery. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
8 | Test the battery voltage circuit of the window sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
9 | Test the low reference circuit of the window sensor for a high resistance, an open, or a short to battery. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 10 |
10 | Inspect for poor connections at the harness connector of the appropriate door module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
11 | Inspect for poor connections at the harness connector of the appropriate window sensor/motor assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
12 | Replace the inoperative door module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 14 | -- |
13 | Replace the inoperative window sensor/motor assembly. Refer to Front Side Door Window Regulator Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
14 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
