Caravan power liftgate

Fix Caravan power liftgate

Diagnose and fix Caravan power liftgate

The Caravan power liftgate incorporates these components:

Power Liftgate Drive Unit
Power Latch and Actuator
Power Liftgate Control Module
Pinch Sensors
Thermistor (Integral part of the right pinch sensor)
Overhead Console, D-Pillar and Key Fob Command Switches
Chime

How the Caravan power liftgate system works

Initiate a caravan power liftgate open/close operation by pressing one of the power liftgate switches located on the overhead console and left D-pillar or by pressing the key fob liftgate button twice. The hardwired buttons connect directly to the power liftgate control module. The module supplies each button with a 5-volt reference signal and a return. When the button is pressed, the control module detects the voltage drop and that acts as the signal to open/close the liftgate.

The power liftgate control module then checks the safety feature inputs and inhibiting conditions before initiating the open/close operation.

Power Liftgate Inhibiting Conditions and safety sensors

The power liftgate module will inhibit liftgate operation if the thermistor in the right side pinch sensor detects ambient tempertures less than -22°F and above 149°F.

The vehicle’s transmission must be in park or neutral

Vehicle speed must be 0-MPH

Vehicle voltage must be within specification

IGN switch must not be in the START position. If the IGN switch is moved to the START position while the power liftgate is in operation, the control module will pause the liftgate open/close operation.

If the vehicle is locked, the power liftgate the exterior handle will not release the latch

If the vehicle’s theft alarm is armed, the overhead switch will not open the liftgate, but the keyfob will work

If a pinch sensor is activated during a power assisted close, the lifgate will reverse direction. If the pinch sensor is still active, the control module will not activate a power close. If the pinch sensor activates during a power close the module will prevent the latch cinch operation.

If the control module detects resistance during liftgate travel, it will reverse operation and travel to full open or full close.

If the control module detects multiple obstacles, it will prevent power assist operation and the door must be closed manually.

Power liftgate resistance obstruction detection

The liftgate drive unit employs a DC motor, chain drive, chain sprockets, full-open switch, housing/bracket assembly and wire harness. Internal motor circuitry provides the liftgate control module with a motor speed signal. This speed signal is used to monitor any resistance of liftgate travel and allows the liftgate control module to detect obstructions and control the liftgate accordingly. The full-open switch is used to let the liftgate control module know when the liftgate is approaching the full open position.

Power liftgate thermistor

The thermistor portion of the right pinch sensor provides the temperature signal to the power liftgate control module. The temperature is provided when the pinch sensor is in an unpinched condition. When pinched, the temperature is unavailable because the thermistor is shorted).

THERMISTOR RESISTANCE

0°C (32°F) 29330 – 35990 ohms
25°C (77°F) 9120 – 10880 ohms
40°C (104°F) 4900 – 5750 ohms

Power liftgate pinch sensors

The power liftgate system utilize two pinch sensors. One pinch sensor is located on each side of the liftgate. These sensors look like weather-strips, however they consist of pieces of electrically conductive rubber (tapeswitch), wires (2), resistor, double-sided tape, and a plastic carrier. The right side pinch sensor contains a thermistor that is integral to the pinch sensor assembly. The thermistor is a temperature sensor used by the power liftgate control module to enable proper liftgate operation in extreme climate conditions. Pinch sensors are used to provide additional protection against vehicle damage or personal injury caused by an obstacle being “pinched” between the liftgate and the liftgate opening of the vehicle.

The pinch sensors are wired in series with the power liftgate control module. If one pinch sensor becomes defective the module will act as though both sensors are defective. The power liftgate latch “Cinching” operation will be disabled if a problem is detected by the control module.

Liftgate cinch/release latch and actuator

Unlike a manual liftgate, a power liftgate has a latch actuator attached to the latch mechanism. The actuator contains a small drive gear that meshes with the latch assembly to perform the power cinch/release function. The latch actuator is controlled by the power liftgate control module, which controls the cinch function and limits actuator current draw to protect the assembly. The latch is located in the lower center of the liftgate assembly and contains integral switches. These switches include, liftgate ajar, secondary, pawl, sector and power liftgate exterior handle.

Caravan Power lifgate inhibit trouble codes

Chrysler uses Mode $06 trouble codes to identify problem with the power liftgate. You must use a MODE $06 capable scan tool to read these codes. Inhibit codes are Mode $06 codes

$80 — Low voltage. Charge or replace the vehicle battery

$82 — Close inhibit, voltage too low. Check power and ground to the liftgate module. Check module voltage reading using a scan tool. Compare to actual voltage check at the module using a meter. If voltage reading vary by 0.5-volts or more, replace the liftgate module

$81 — Open inhibit. Voltage too high. Check charging system voltage

$83 — Close inhibit. Voltage too high. Check module voltage reading using a scan tool. Compare to actual voltage check at the module using a meter. If voltage reading vary by 0.5-volts or more, replace the liftgate module

$84 — Open inhibit temperature too low. Temperature was too low when open/close was requested. <-22°F

$86 — Close inhibit temperature too low. Check reading from thermistor. If reading is off, check for high resistance in thermistor circuit. Check signal and ground voltages. Check for inoperative thermistor and pinch sensor.

$85 Open inhibit temperature too high. Temperature was above 149°F when the operation was attempted

$87 Close inhibit because temperature was too high. Check for short or partial short to ground to right pinch sensor/thermistor circuit signal. Repair as necessary.

$88 Close inhibit due to left pinch sensor active. The pinch was activated prior to activation of power close cycle. Check for obstructions that might cause the pinch sensor activation. Check for pinch sensor short to ground on left pinch sensor signal circuit. Measure pinch sensor resistance in an unpinched state. Reading should be 9KΩ or more with connector unplugged. With connector the reading should be approx. 5V.

$89 Close inhibit due to right pinch sensor active. The pinch was activated prior to activation of power close cycle. Check for obstructions that might cause the pinch sensor activation. Check for pinch sensor short to ground on left pinch sensor signal circuit. Measure pinch sensor resistance in an unpinched state. Reading should be 9KΩ or more with connector unplugged. With connector the reading should be approx. 5V.

$8A Open inhibit due to not in park/neutral. Driver attempted to open lifgate when vehicle was not in park or neutral.

$8B Close inhibit due to not in park/neutral. Driver attempted to close lifgate when vehicle was not in park or neutral.

$8C Open inhibit due to non-zero vehicle speed. Driver attempted power liftgate open operation when vehicle was moving.

$8D Close inhibit due to non-zero vehicle speed. Driver attempted power liftgate close operation when vehicle was moving.

$8F Close inhibit due to IGN in start position. Driver attempted power liftgate close operation with IGN switch in start position.

$90 Open inhibit in-plant mode. Must perform a learn cycle for control module.

$91 Open inhibit in-plant mode. Must perform a learn cycle for control module.

$92 Open inhibit due to gear/speed mismatch. Liftgate will not open due to conflict between PRNDL and vehicle speed inputs.

$93 Close inhibit due to gear/speed mismatch. Liftgate will not close due to conflict between PRNDL and vehicle speed inputs.

$94 Open inhibit due to not fully open or fully closed. Driver placed lifgate in primary or secondary latch position when liftgate was open.

$95 Latch release inhibit due to lock engaged. Vehicle was locked when driver attempted to release the liftgate latch using exterior handle.

$96 Latch cinch aborted due to left pinch sensor active. Pinch sensor was activated while latch was cinching. Check for obstructions.

$97 Latch cinch aborted due to rightt pinch sensor active. Pinch sensor was activated while latch was cinching. Check for obstructions.

$98 Open cancelled due to handle active. Driver attempted handle activation during a power open cycle.

$99 Open cancelled due to a key fob button activation.

$9A Open cancelled due to overhead I/P active. Power open operation cancelled during first two seconds by an overhead console liftgate switch signal

$9B Close cancelled due to exterior handle active. Driver attempted to close using exterior handle during a power close cycle.

$9C Closed cancelled due to remote keyless entry active. Keyfob buttons pressed during close operation.

$9D Close cancelled due to overhead I/P active. Power close operation cancelled during first two seconds by an overhead console liftgate switch signal

$9E Close cancelled due to left pinch sensor detected. Check for obstructions. Check left pinch sensor readings.

$9F Close cancelled due to right pinch sensor detected. Check for obstructions. Check right pinch sensor readings.

$A1 Open reversal due to user input. Driver operated key fob button or overhead console switch during a power open cycle.

$A2 Close reversal due to user input. Driver operated key fob button or overhead console switch during a power close cycle.

$A3 Close reversal due to left pinch sensor detection. Check for obstruction and check pinch sensor readings.

$A4 Close reversal due to right pinch sensor detection. Check for obstruction and check pinch sensor readings.

$A5 Close reversal due to exterior handle activation. Driver attempted to use exterior handle during close operation.

$A6 Open aborted due to exterior handle activation. Driver attempted to use exterior handle during open operation.

$A7 Open obstacle. Obstacle detected during open cycle.

$A8 Close obstacle Obstacle detected during close cycle.

$A9 Wrong software version. Current power liftgate control module software version does not match bootloader and possibly hardware version

$AA Latch is not near secondary state. Driver has placed liftgate in primary or secondary latch position when the liftgate was open.

$AB Open inhibit VTA armed. Liftgate operation initiated while vehicle theft alarm was active.

The power liftgate control module then interprets the information to confirm safety requirements are met before applying power to the power liftgate motor to start a power cycle.

The power liftgate control module has the ability to relearn. After 8 miles have been recorded on the odometer, anytime the liftgate is fully opened and fully closed using the automatic system, the module will learn from its cycle. If a replacement power liftgate component is installed or a liftgate adjustment is made, the module will relearn the effort and time required to open or close the liftgate. This learn cycle can be performed with a Diagnostic Scan Tool or with a complete cycle of the liftgate, using any of the command switches, (Refer to 08 – Electrical/Power Sliding Door/Standard Procedure) for detailed instructions.