Tailgate System: Notes
Check the following items prior to performing Power Tailgate System (PTG) service.
- Manual Movement
Make sure the tailgate moves manually. Place the ON/OFF Switch located in the glove box area in the OFF position. Move the gate manually and check for proper gate fit and latch effort. Check for interference with other body parts such as latch striker, gate guide bumpers, and weather seals. Correct these problems first. The PTG system works best when the manual operation is smooth and correct.
- Battery Voltage
Make sure the battery is fully charged. The PTG system is an electronic device and requires a minimum battery voltage to operate. The PTG Control Module (PTGM) monitors the battery voltage present at the PTGM battery input terminal and will not permit operation if the battery voltage is out of range.
- Fuses
Check to make sure that the fuses are intact.
Two fuses protect the battery supply to the PTGM, one for Power, and one for Logic Signals.
Power Fuse (30A) is located in the Main Fuse Block in the Engine Room and the Memory Fuse (15A, Shunt Switch) for the logic signal line is located in the fuse box under the steering column.
- System Response
Spend some time to observe how the system responds to each different input signal upon change in the Central Lock/Unlock status as well as the ON/OFF Switch status. The system may react differently to a certain input such as the RKE or the Master Open/Close Switch than the other inputs such as the Local Open/Close Switch and the Outside Handle Switch.
Check also to see if there is only partial trouble with the system such as only power closing is in trouble while power opening function works fine. This kind of observation will help you narrow down the possible root-causes.
- Vehicle on Steep Grade or Uneven Surface
Make sure the customer has not been operating the PTG system when the vehicle is parked on a steep grade (greater than 20%) or an uneven surface such as with one or more wheels on a curb or in a hole or when the vehicle is raised on a jack. The system may or may not properly operate in those extreme conditions. Also the force of gravity and normal flex of the vehicle body might have damaged the system interface if power operation has ever been tried in such unstable conditions.
- Obstacle Detection
The obstacle detection force is not adjustable. Factors that may affect the force are vehicle grade, battery voltage, or vertical location of the tailgate. Soft obstacle will increase the effort to reverse the gate. To check the obstacle detection force, simply stand against the tailgate and push it while it is power closing. Obstacle detection force in power opening is usually higher than in closing.
- Build Variation
The tailgates are not identical. Open and close times and obstacle detection efforts may vary when comparing the vehicles. This is normal and is caused by vehicle build conditions such as body-gate fit, gate hinge balance, and seal force.
- Hi-Scan Diagnostic Tools
Connect the Hi-Scan tool to the K-line OBD connectors and check the status of the system.
Diagnostic Trouble Codes and the Service Data will be useful to diagnose the trouble.
- Hi-Scan Tool Software Program (ROM PACK) Update There may be a new update release of the scanner software program that complies with the change of the system or vehicle interface available for you.NOTE: The Power Tailgate Control Module (PTGM) controls the Drive Unit Motor, Clutch, and the Power Latch Actuators. The PTGM responds to commands from the external switches such as the Master Open/Close, Local Open/Close, RKE, or from the Outside Handle Switch. It cannot initiate a power open operation without a request from one of the inputs and then only if the vehicle conditions are correct, e.g.: vehicle not moving, unlocked, battery voltage within range, etc.
Chime shall operate when a power operation cannot be performed as requested (a one time chime sound). Chime shall operate as well but three consecutive times when an obstacle has been detected or the system could not finish power operation as expected. There is no chime indication related with DTC set.
| CONDITION | POSSIBLE CAUSES | CORRECTION |
|---|---|---|
| Tailgate does not initiate power open or power close upon switch input, without any indication of Chime | Battery voltage at PTGM is too low (Battery voltage at PTGM input terminal should be higher than 9.0V to start operation, and sustain 8.0V minimum to continue operation) | Check for proper voltage at the PTGM. Charge battery. |
| Blown fuse | Check for blown Memory Fuse (a 15A fuse in the fuse box under steering column). | |
| Bad electrical connection | Check to see if diagnostic communication is possible through Hi-scan tool.
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| Wiring problems (system or vehicle) | Troubleshoot using electrical schematics. Check electrical continuity of wire harness. Refer to SYSTEM WIRING DIAGRAMS. Check for switch status with Hi-scan tool. |
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| Failure of Unlatch Motor | Refer to "Unlatch Motor does not power unlatch without sound indication". | |
| False indication of switches or DTC being set | Check for switch status with Hi-scan tool. Check for diagnostic trouble codes. |
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| Failure of Anti-Pinch Strip (APS) | Check for APS related diagnostic trouble codes. Check APS connector and wiring. |
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| Faulty condition generated in body control modules including BCM, DDM and ADM where door Lock/Unlock signal is being processed. | Check BCM and DDM/ADM diagnostic trouble codes for ECU failures. | |
| Tailgate does not power open upon switch input with indication of Chime or Unlatch Motor operating sound | Battery voltage at PTGM is out of operating range (Battery voltage at PTGM input terminal should be higher than 9.0V to start operation, and sustain 8.0V minimum to continue operation) | Check for proper voltage at the PTGM. |
| Failure in tailgate unlatch mechanism | Refer to "Unlatch Motor does not power unlatch with sound indication". | |
| Failure in Power Latch | Check latch assembly. Check for foreign matter preventing latch operation. |
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| Binding or sticking of components | Establish location of binding and replace necessary components | |
| False indication of switches or PRNDL out of Park with Ignition ON (Park or VSS signal error inhibits power open only when ignition is ON) | Check for switch status with Hi-scan tool. | |
| Power loss during Tailgate operation (No automatic recovery) | Wiring problems (system or vehicle) | Troubleshoot using electrical schematics. Refer to SYSTEM WIRING DIAGRAMS. |
| Battery voltage at PTGM is too low (Battery voltage at PTGM input terminal should be higher than 9.0V to start operation, and sustain 8.0V minimum to continue operation) | Check for proper voltage at the PTGM. | |
| Failure of Power Tailgate or Body Control Module | Check for diagnostic trouble codes. | |
| Failure of drive motor | Check for diagnostic trouble codes. Examine and test motor. |
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| RKE or Master Open/Close Switch does not power trigger Tailgate, while Local Open/Close Switch and Outside Handle Switch do (Main ON/OFF=ON) | Failure of Master Open/Close switch assembly | Check for switch status using Hi-scan tool. Check Master Open/Close switch assembly. |
| Failure of RKE. | Check RKE battery. Check RKE coding status. |
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| Wiring problems - vehicle body wiring | Refer to SYSTEM WIRING DIAGRAMS. Check for switch status using Hi-scan tool. |
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| Failure of BCM (Body Control Module) or the switch circuit | Troubleshoot using body diagnostic article. | |
| Unlatch Motor does not power unlatch without sound indication - Latch will not be released from primary position | Failure of Unlatch Motor | Try operating outside handle switch. Examine and test Unlatch Motor. |
| Unlatch Motor wiring problem (Unlatch Motor short high or short low) | Check for diagnostic trouble codes. | |
| Unlatch Motor does not power unlatch with sound indication from Tailgate chime or Unlatch Motor - Fail to release latch from primary position | Battery voltage at PTGM is low (Battery voltage at PTGM input terminal should be higher than 9.0V to start operation, and sustain 8.0V minimum to continue operation) | Check for proper voltage at the PTGM. |
| Electrical connection problem from outside handle switch | Check for switch status using Hi-scan tool. Check outside handle switch assembly. |
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| Wiring or electrical connection problems | Check wire connections. Check for diagnostic trouble codes. |
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| Binding or sticking of components | Establish location of binding and adjust or replace necessary components. | |
| Failure of Power Latch | Check for diagnostic trouble codes. Check latch assembly. |
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| Tailgate does not stay open | Failure of Gas Strut (One or both Gas Struts have low output force) | Examine gas struts. |
| Tailgate immediately power closes after a power open to the full open position | Gas Strut cannot hold Tailgate open at full open position causing the PTGM Fail Safe Mode to power close the Tailgate (One or both Gas Struts have low output force) | Examine gas struts. |
| Tailgate stops power operation in middle of travel | Failure of Optical Sensor | Check for diagnostic trouble codes. Check optical sensor attachment. Reset PTGM. |
| Drive Unit failure | Check for diagnostic trouble codes. | |
| Tailgate does not full close to primary latch position - Either reverse or give up cinching after 5 seconds maximum with chime sounding 3 times | Tailgate misalignment | Check latch and striker alignment. |
| Check guide bumper alignment. | ||
| Check tailgate hinge alignment. | ||
| Check intervention of trim components. | ||
| Binding or sticking of components | Establish location of binding and adjust or replace necessary components. | |
| Tailgate seal force too high | Check manual seal force. Check if tailgate can be manually closed from secondary to primary when pushed from outside. Inspect seals for damage, mis-assembly, foreign matter or other possible obstruction. |
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| High manual opening effort | Failure of gas struts | Examine gas struts. |
| Check for broken attachments. | ||
| Drive unit jammed or did not disengage | Troubleshoot using Body Diagnostic article, Replace components, if necessary. | |
| Binding or sticking of components | Establish location of binding and replace necessary components. | |
| Tailgate continues to power close | Failure of latch assembly | Check wire connections. Check detent switch status with Hi-scan tool. Replace latch. |
| Check for foreign matter. | ||
| Troubleshoot using body diagnostic article. | ||
| Wiring problems (system or vehicle) | Troubleshoot using electrical schematics. Refer to SYSTEM WIRING DIAGRAMS. |
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| ECU or PTG Drive Unit failure | Check for diagnostic trouble code. Reset PTGM. |
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| Tailgate continues to power open (Does not power close when the Tailgate is in full open position) | System lost position information | Manually close tailgate and try power open. Reset and re-initialize the system. |
| Wiring problems (system or vehicle) or Latch assembly switch failure | Troubleshoot using electrical schematics. Refer to SYSTEM WIRING DIAGRAMS. |
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| ECU or PTG Drive Unit failure | Check for diagnostic trouble code. Reset PTGM. |
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| Tailgate will not power open or power close when the Tailgate is in full open position | System is not properly initialized after being open more than 6 hours | Manually close tailgate and try power open. Reset and re-initialize the system. |
| Tailgate opens very slowly | Battery voltage at PTGM is low (Battery voltage at PTGM input terminal should be higher than 9.0V to start operation, and sustain 8.0V minimum to continue operation) | Check for proper voltage at the PTGM. |
| Failure of Gas Strut (One or both Gas Struts have low output force) | Examine gas struts. | |
| Binding or sticking of components | Establish location of binding and replace necessary components. | |
| Grade of vehicle too steep for power operation | Operate Tailgate manually. | |
| Failure of drive motor | Check for diagnostic trouble codes. Examine and test motor. |
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| Squeaks, rattles or any other strange noise heard from the drive unit or Power Latch assembly | Foreign material in the drive unit or tailgate | Check and remove foreign material. |
| Worn or loose components, or contaminated components in the drive unit assembly (or power latch assembly) | Check and tighten loose components or replace the assembly in case noise does not disappear. | |
| Tailgate opens unexpectedly | Accidental activation or failure of open/close command switch | Check for shorted or defective switch. |
| Failure of latch assembly | Check wiring connections. | |
| Check latch switch status with Hi-scan tool. |