Rear Windsreen wiper motor runs continuousley in

How do you know the BCM is at fault ? Did you hook up a factory or someother type professional scan tool an check for DTC'S - diagnostic trouble codes ? Did you view how these system work in factory sevice repair information ? Did you use a wiring diagram an DVOM - digital volt ohmmeter an test electrical circuits ?

The BCM has nothing to do with the memory seats .
Memory Seat System Components
The memory seat system consists of the following components:
• Power Seat Switch
• Seat Horizontal Motor
• Seat Front Vertical Motor
• Seat Rear Vertical Motor
• Seat Recliner Motor
• Driver Seat Module
• Memory Seat Switch
Memory Seat System Description
Battery voltage is supplied to the driver seat module through the power seat circuit breaker. The driver seat module supplies the seat adjuster switch assembly with a battery positive reference voltage. While the seat adjuster switches are in an inactive state the switch contacts are closed to the adjuster switch ground circuit. When a seat adjuster switch is pressed to an active state the switch contact is closed to the reference voltage circuit. Battery voltage on a switch signal circuit indicates to the driver seat module the switch status is active. Each seat adjuster motor is controlled by the driver seat module through 2 motor control circuits. While the seat adjuster motors are in an inactive state the motor control circuits are closed to ground circuit contacts within the driver seat module. The driver seat module operates the seat adjuster motors by switching one of a motor's control circuits to battery voltage. The seat adjuster motors are bidirectional and the direction of adjuster motor rotation is determined by which of the adjuster motor control circuits is switched to battery voltage while the other remains grounded.


Memory Set/Recall Operation
The driver seat adjuster motors are equipped with potentiometer type position sensors used by the driver seat module to determine the seat position. The position sensors are supplied with 5-volt reference and ground circuits from the driver seat module. The position sensor signal circuits are referenced from ground within the driver seat module. The signal circuit voltage levels monitored by the driver seat module range from 0.39 - 4.58 volts and are determined by the wiper locations on the resistors within the motor position sensors. The position sensor circuit voltage levels are used by the driver seat module to determine the seat position when storing or recalling memory position settings.
The memory recall switch assembly on the driver's door provides inputs to the driver door module. Battery voltage is supplied to the memory recall switch assembly from the driver door module. When a memory recall 1, 2, or EXIT switch is pressed, the switch contacts close the appropriate switch signal circuit to the battery voltage supply circuit within the memory recall switch assembly. When the driver door module receives active switch signals from the memory recall switch assembly, the appropriate commands are sent to the driver seat module using the Class 2 Serial Data circuit.
Memory seat recall operation is allowed only with the transmission selector lever in the PARK position while the ignition is on. The transmission selector lever position data is provided to the driver seat module by a message through the Class 2 Serial Data circuit.
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Rear Wiper/Washer System Components
The rear wiper/washer system consists of the following components:
• Rear window wiper motor
• Rear washer pump
• Rear wash relay
• Rear wiper/washer switch
• RR WIPER Circuit Breaker 15A / ENDGLASS REG Circuit Breaker 30A
• WASH 20A fuse
• Body control module (BCM)
• Liftgate control module (LGM) / End gate module (EGM)


Rear Wiper Operation (with LGM)
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the LGM by the BCM, as a message on the serial data circuit. The rear window wiper motor is controlled by the LGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM during ignition on, accessory or RAP power modes. The rear wiper/washer switch is composed from a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The LGM controls rear wiper motor operation through the rear window motor speed signal circuit. The rear window motor speed signal circuit is supplied a battery positive reference voltage by the rear window wiper motor module and is pulse width modulated to ground by the LGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The liftglass and liftgate ajar switches are inputs to the LGM and must be in an inactive state in order for rear wiper washer system operation to be enabled. When an ajar switch is active the LGM suspends wiper motor operation directly and sends the ajar switch status messages over the serial data circuit enabling the BCM to suspend washer pump operation.


Rear Wiper Operation (with EGM)
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the EGM by the BCM, as a message on the serial data circuit. The rear window wiper motor is controlled by the EGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM. The rear wiper/washer switch is composed from a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The EGM controls rear wiper motor operation through the rear window motor speed signal circuit. The rear window motor speed signal circuit is supplied a battery positive reference voltage by the rear window wiper motor module and is pulse width modulated to ground by the EGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The rear window motor park signal circuit provides position status of the rear wiper to the EGM.
The rear wiper and washer operation is allowed if the following conditions are true:
• Power mode is run or accessory.
• Lower left ajar switch is closed.
• Upper left ajar switch is closed.
• Upper right ajar switch is closed.
• Upper left dome switch is closed.
• The end gate window is fully closed.
• No end gate window express down, up, or down is requested.
• No gate swing open or drop open is requested.
If rear wiper/washer operation is attempted and the end gate window is open the driver information center (DIC) displays "Tailgate Glass Down". If the rear wiper is not in the park position and an attempt to open end gate window is done, the DIC displays "Rear Wiper Obstruction".


Your best bet , take it to a qualified repair shop because you have no idea how these systems work .

Did you check fuse's & relays ?
Rear Window Wiper Operation
The rear wiper motor is controlled by the SJB. The SJB supplies power to the rear wiper motor from the integrated rear wiper relay. The SJB will activate the relay when all of the following conditions are met:

• Ignition switch is in the ON position
• Liftgate glass and liftgate are closed
• Multi-function switch is in the ON or intermittent position

The SJB also supplies voltage to the rear wiper motor from SJB fuse 21 (15A) when the ignition switch is in the ON position. This power feed is used to continue the wipe cycle when the multi-function switch is turned to the OFF position. The SJB receives inputs from the multi-function switch that applies ground to the low speed wipe input or applies ground to the intermittent wipe input. When either of these circuits are grounded, the SJB activates the integrated rear wiper relay and power is supplied to the rear wiper motor to move the rear wiper motor from the park position. An internal switch in the rear wiper motor then moves to the run position which connects the accessory relay power to the rear wiper motor. When the rear wiper motor returns to the park position, the internal switch in the rear wiper motor moves back to the park position. If the multi-function switch is in the ON position, the rear wiper relay is still activated, power is supplied to the rear wiper motor, and the wipe cycle starts again. If the multi-function switch is in the intermittent position, the rear wiper relay does not activate until the predetermined dwell time has elapsed, at which time the SJB activates the rear wiper relay and the wipe cycle starts again. The SJB is the smart junction box .(computer )

Rear Washer System
The SJB supplies power to the rear washer pump from fuse 21 (15A) when the ignition switch is in the ON or ACC position. The rear washer pump receives ground from the multi-function switch when the wash function is turned ON. The multi-function switch also signals the SJB when the rear wash is activated and the SJB then activates the rear wiper.

Do you know how these wipers Work / what controls them ? Do you know what a smart junction box is ?
Rear Window Wiper Operation
The rear wiper motor is controlled by the SJB. The SJB supplies power to the rear wiper motor from the integrated rear wiper relay. The SJB will activate the relay when all of the following conditions are met:

• Ignition switch is in the ON position
• Liftgate glass and liftgate are closed
• Multifunction switch is in the ON or INTERMITTENT position

The SJB also supplies voltage to the rear wiper motor from SJB fuse 21 (10A) when the ignition switch is in the ON position. This power feed is used to continue the wipe cycle when the multifunction switch is turned to the OFF position. The SJB receives inputs from the multifunction switch that applies ground to the low speed wipe input or applies ground to the intermittent wipe input. When either of these circuits are grounded, the SJB activates the integrated rear wiper relay and power is supplied to the rear wiper motor to move the rear wiper motor from the PARK position. An internal switch in the rear wiper motor then moves to the RUN position which connects the accessory relay power to the rear wiper motor. When the rear wiper motor returns to the PARK position, the internal switch in the rear wiper motor moves back to the PARK position. If the multifunction switch is in the ON position, the rear wiper relay is still activated, power is supplied to the rear wiper motor, and the wipe cycle starts again. If the multifunction switch is in the INTERMITTENT position, the rear wiper relay does not activate until the predetermined dwell time has elapsed, at which time the SJB activates the rear wiper relay and the wipe cycle starts again.

Do you know what DTC'S - diagnostic trouble codes are ?
Smart Junction Box (SJB) Diagnostic Trouble Code (DTC) Index DTC Description Source Action B1244 Wiper Rear Motor Run Relay Coil Circuit Failure SJB If the rear wiper is inoperative, Go To Pinpoint Test B . If the rear wiper is always ON, Go To Pinpoint Test D . B1245 Wiper Rear Motor Run Relay Coil Circuit Short to Battery SJB Go To Pinpoint Test B . B1614 Wiper Rear Mode Select Switch Circuit Failure SJB Go To Pinpoint Test D .
Did you have it checked for DTC'S ?

Did you check the fuse ? Do you hear the wiper motor running ? If the fuse is good you would need to test the electrical circuit for the wiper motor ,viewing a wiring diagram an then use a DVOM - digital volt ohmmeter to test
What body type is it ? Vin 6 or 3 could have a circuit breaker for power supply or fuse ,both are located in the rear fuse block .

Rear Wiper/Washer System Components
The rear wiper/washer system consists of the following components:
• Rear window wiper motor
• Rear window washer fluid pump
• Rear wash relay
• Rear window wiper/washer switch
• RR wiper 15A circuit breaker
• WASH 20A fuse
Rear Wiper/Washer System Controls
• Body control module (BCM)
• Liftgate control module (LGM)
• Rear wiper/washer switch

Here is how it is controlled

Rear Wiper/Washer System Operation
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the liftgate control module (LGM) by the BCM as a message on the serial data circuit, and the rear window wiper motor is controlled by the LGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM during ignition on, accessory or RAP power modes. The rear wiper/washer switch is a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The LGM controls rear wiper motor operation through the rear wiper motor control circuit. The rear wiper motor control circuit is supplied a battery positive reference voltage by the rear wiper motor module and is pulse width modulated to ground by the LGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The liftglass and liftgate ajar switches are inputs to the LGM and must be in an inactive state in order for rear wiper washer system operation to be enabled. When an ajar switch is active the LGM suspends wiper motor operation directly and sends the ajar switch status messages over the serial data circuit enabling the BCM to suspend washer pump operation. The rear window washer pump is controlled by the BCM through the rear washer relay. Battery positive voltage is supplied to the coil and switch sides of the rear washer relay. When the rear window wash request is active the BCM energizes the relay by grounding the relay coil through the rear washer relay control circuit. When the relay is energized battery positive voltage to the relay switch is supplied to the washer pump control circuit.

Your best bet mite be to have a qualified repair shop check for codes in the BCM or LGM
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DTC B1017 or B3970

The rear wiper motor is supplied battery positive voltage and ground. The liftgate control module controls rear wiper motor operation through the rear wiper motor control circuit. The rear wiper motor control circuit is supplied a battery positive reference voltage by the rear wiper motor module and is pulse width modulated to ground by the liftgate control module. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode.

There are something's involved that you are not aware of , or familiar with . Electronic control modules .
Rear Wiper/Washer System Controls
• Body control module (BCM)
• Liftgate control module (LGM)
• Rear wiper/washer switch
Do you know what a serial data network is ?
Rear Wiper/Washer System Operation
The rear window wiper/washer switch is an input to the BCM. The requested rear wiper mode is sent to the liftgate control module (LGM) by the BCM as a message on the serial data circuit, and the rear window wiper motor is controlled by the LGM. The switch power circuit to the rear wiper/washer switch is a 12-volt reference supplied by the BCM during ignition on, accessory or RAP power modes. The rear wiper/washer switch is a series of resistors and the switch position is determined by the voltage of the rear wiper/washer switch signal circuit to the BCM. The rear wiper/washer switch has continuity at all times and the BCM expects a rear wiper/washer switch signal voltage in all switch positions including OFF. The rear wiper motor is supplied battery positive voltage and ground. The LGM controls rear wiper motor operation through the rear wiper motor control circuit. The rear wiper motor control circuit is supplied a battery positive reference voltage by the rear wiper motor module and is pulse width modulated to ground by the LGM. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode. The liftglass and liftgate ajar switches are inputs to the LGM and must be in an inactive state in order for rear wiper washer system operation to be enabled. When an ajar switch is active the LGM suspends wiper motor operation directly and sends the ajar switch status messages over the serial data circuit enabling the BCM to suspend washer pump operation. The rear window washer pump is controlled by the BCM through the rear washer relay. Battery positive voltage is supplied to the coil and switch sides of the rear washer relay. When the rear window wash request is active the BCM energizes the relay by grounding the relay coil through the rear washer relay control circuit. When the relay is energized battery positive voltage to the relay switch is supplied to the washer pump control circuit.

Your best bet , take it to a qualified repair shop and have it checked for DTC'S - diagnostic trouble codes .
DTC B1017 or B3970
The rear wiper motor is supplied battery positive voltage and ground. The liftgate control module controls rear wiper motor operation through the rear wiper motor control circuit. The rear wiper motor control circuit is supplied a battery positive reference voltage by the rear wiper motor module and is pulse width modulated to ground by the liftgate control module. The duty cycle of the pulse width modulation determines the rear wiper motor operating mode.
DTC B3799

2
Turn the ignition ON.
Operate the rear wiper switch through all the switch positions.
Does the rear window wiper operate normally?
--
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Install a scan tool.
Display the liftgate control module data list.
Observe the following parameters while operating the respective switches. Refer to Scan Tool Data List for typical values.
• Liftgate Ajar Switch
• Liftglass Ajar Switch
Did the scan tool indicate the correct switch positions?
--
Go to Step 4
Go to Courtesy Lamps Inoperative in Lighting Systems
4
Observe the requested rear wiper parameter in LGM data list.
Operate the rear wiper switch through all the switch positions.
Does the scan tool indicate the correct requested rear wiper parameter in relation to the switch position?
--
Go to Step 5
Go to Step 6

relay

a broken wiper controller...
(its in a box the size of a relay under the dash) costs about £15 - $20 tops.
pointless to try repair the controller- most car shops should stock the part, just phone around. .

what is P13K?

check the fuse first. dealer can hook up NGS Tester and get fault codes to see what is wrong.

Principles of Operation
NOTE: The generic electronic module (GEM) will not activate the rear wiper system if either the liftgate or the liftgate glass is ajar. If either the liftgate or the liftgate glass becomes ajar while the rear wiper is in operation, the GEM will park the rear wiper motor.
There are two distinct modes of wiper operation:

• Off Mode: In this mode, there is no rear wiper activity, and the wiper motor will be in the PARK position.
• Interval Mode: This mode is selected when the rear wiper switch is in either the Interval 1 or 2 position. When this mode is selected, the rear wiper motor is driven up onto the glass by activating the rear wiper UP relay. When the wiper motor HIGH/LOW/PARK position input reaches the high position, the UP relay is deactivated and the DOWN relay is activated to reverse the wiper motor direction. When the wiper motor reaches the LOW position, as determined by the HIGH/LOW/PARK position input, the GEM deactivates the DOWN relay and will begin a new wiper cycle 1 to 10 seconds later, depending on the interval position selected.

To engage the rear window washer, rotate the rear window washer selector downward to the WASH position. The rear window wiper will run as long as the WASH position is selected. When the rear window washer selector returns to the OFF, INT 1 or INT 2 position, the washer will stop immediately, but the rear window wiper will continue for two to three sweeps and then return to its previous mode of operation.
The low washer fluid indicator chime warns that the washer fluid level is low. The low washer fluid indicator chime is a single tone with a duration of one second. The chime will sound when the low washer fluid indicator is initially activated.
The low washer fluid indicator warns that the fluid level in the washer reservoir is low. The low washer fluid indicator will illuminate when the washer fluid level is low and the ignition switch is in the RUN position.
The low washer fluid indicator will deactivate when the washer fluid reservoir is filled and the ignition switch has been cycled from RUN to OFF, then to RUN.
Inspection and Verification

1. The wiper/washer system is a generic electronic module (GEM) controlled system; refer to Section 419-10 .

1. Verify the customer concern by operating the wiper/washer system.

1. Visually inspect for obvious signs of mechanical and electrical damage.

Visual Inspection Chart Mechanical Electrical

• Hoses to windshield washer pump
• Wiper linkage

• Fuses 6 (5A), 8 (5A), 15 (5A), and 20 (5A)
• Wiring harness
• Loose or corroded connector(s)
• Relays
• Motors
• Multifunction switch
• Washer fluid level switch

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• The wipers are inoperative — rear

• Fuses 6 (5A), 8 (5A), 15 (5A), and 20 (5A).
• Circuitry.
• GEM.
• Multifunction switch (wiper/washer switch).
• Rear wiper up relay.
• Rear wiper down relay.
• Rear wiper motor.

my 2004 expedition had same problem, if you take apart the shaft that goes thru the glass it will be full of dirt, clean ,lubricate and reinstall, you may have to replace the O-ring on the shaft. a 20 minute job, very easy fix

Principles of Operation
Operation of the windshield wiper and washer is controlled by the front wiper/washer amplifier assembly. The front wiper/washer amplifier input comes from the multifunction switch by means of a voltage divider circuit. A constant voltage is applied to the multifunction switch by the front wiper/washer amplifier. When the multifunction switch is moved into the LO, HI, or intermittent position, the voltage is directed through a series of resistors. This results in various voltages being returned to the module for each switch position. The module then grounds the appropriate circuit, based on the voltage signal received back from the multifunction switch. This causes the wipers to run intermittently, or at the appropriate speed. Voltage is supplied to the wiper motor by the CJB fuse F46 (20A).
When the multifunction switch wash button is depressed, it bypasses all of the resistors returning a full voltage signal to the module. The module then grounds the appropriate circuits to operate the windshield washer pump for as long as the switch is depressed. The windshield wiper speed is dependent on the position of the windshield wiper/washer switch.
Voltage for the windshield washer pump is also provided by CJB fuse F46 (20A).
Operation of the rear wiper and washer is controlled by the rear wiper/washer switch.
Voltage is supplied to the rear window wiper motor by the fuse junction panel fuse F44 (10A).
The rear window wiper motor ground is made or broken by the rear wiper/washer switch. When the rear wiper/washer switch is moved into the WIPER position, it grounds the rear window wiper motor circuit, causing the rear window wiper motor to run once every 10-15 seconds.
Voltage to the rear washer pump motor is also supplied by the CJB fuse F44 (10A). The rear washer pump is directly controlled by the rear wiper/washer switch which makes or breaks the ground for the washer pump motor, depending upon its position.
If the vehicle is equipped with a movable liftgate glass, a liftgate glass switch is utilized to prevent rear window wiper operation when the liftgate glass is open. This same switch also causes the rear window wiper to drop down approximately three inches when the liftgate glass latch is released.
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• The wipers stay on continuously — rear wiper

• Circuit.
• Rear wiper/washer switch.

• GO to Pinpoint Test L .

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Measure the resistance between rear wiper/washer switch C288 pin 6, component side and rear wiper/washer switch C288 pin 2, component side.

• Is the resistance less than 5 ohms with the switch depressed, and greater than 10,000 ohms with it released?

Yes GO to L2 .
No INSTALL a new rear wiper/washer switch. TEST the system for normal operation.

Measure the resistance between rear wiper/washer switch C288 pin 6, circuit WB08 (BU/YE), harness side and ground.

• Is the resistance greater than 10,000 ohms?

Yes INSTALL a new rear wiper /washer switch. TEST the system for normal operation.
No REPAIR circuit WB08 (BU/YE). TEST the system for normal operation.