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None < LGM - liftgate control module inside the lift gate does .
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)
Your best bet , take it to a qualified repair shop. You have no idea of the complexity of these system's . Communication network between modules etc..... Could have DTC'S diagnostic trouble code's stored in the liftgate control module . An auto parts stores can not read these codes .
Power Door Lock Operation
The power door lock switches are integral components of the DDM and PDM. The switches are two position normally open rocker switches. When placed in either the lock or unlock positions, the switches provide a direct input to the DDM or PDM. The DDM or PDM monitors these inputs and sends a Class 2 message indicating a change in the switch's respective position. Modules which activate the power door lock motors receive the Class 2 message and activate the motor in the appropriate direction to lock or unlock the vehicle's doors and liftgate. The modules which activate the power lock motors are:
• DDM (driver door lock actuator).
• PDM (passenger front door lock actuator).
• BCM (both rear door lock actuators).
• LGM (liftgate door lock actuator).
The DDM, PDM and LGM are directly connected to the respective door lock actuator through the door lock motor lock and unlock circuits. Once a door lock or unlock request has been received, the module will supply battery voltage to one side of the actuator and ground the other causing the doors to lock or unlock.
Hi Travis , lets see if we can help you ! First off here is a description of how the brake light circuit works , you need a good understanding of how it works before you can fix it. Stop Lamps
The 15-amp STOP fuse located in the body control module (BCM) supplies battery positive voltage to the normally open stop lamp switch. When the driver presses the brake pedal, the switch contacts close and battery positive voltage is supplied to both left and right stop lamp assemblies and the center high mounted stop lamp (CHMSL), through the BCM. The stop lamps are grounded at G401 and G403.
Do you know what a BCM is ? The body control module ! An electronic module .Just like the PCM/ECM - engine computer but for the body thing's ,light's , anti-theft system ,power door lock etc..
The body control module (BCM) has a bussed electrical center integrated into the housing. Body control relays and fuses are installed directly on the BCM which simplifies wiring and junction blocks on the vehicle. The body control system consists of the BCM and its associated controls. Battery positive voltage is provided to the BCM from the instrument panel (I/P) BATT 2 fuse in the Underhood fuse block. The module grounds are wired to ground G201 and G301. The BCM is wired to the Class 2 serial data communication bus as well as discrete input and output terminals to control the functions of the vehicles body .
With starting problems an the brake lights problem you may have a BCM problem , could have DTC's - diagnostic trouble codes stored in the BCM . This would have to be checked at a GM dealer or some other independent repair shop with a professional grade scan tool .
The ignition switch is an input to the BCM , when it receives a start input the BCM energizes the run / crank relay an other things ! Relay Controlled Power Mode
The BCM uses the discrete ignition switch inputs Off/Run/Crank, Accessory and Run/Crank to distinguish the correct power mode. These circuits are also routed to the Run/Crank and Accessory relays for relay controlled power feeds during the appropriate power mode.
The relay uses a Hot At All Times B+ power source derived from the underhood electrical center. The Run/Crank relay supplies a power signal to the following circuits when the a Run or Crank power mode is selected:
Backup lamp circuit
Electronic brake control module (EBCM)
Engine control module (ECM)
Ignition control module (ICM)
Park neutral position switch
Transmission circuit 1 and 2
This is not something for a do it yourselfer , this is dealer or like I said a independent ASE certified repair shop .
The power door locks are controlled by the BCM -body control module ! The door lock switch is an input to the BCM .
The BCM, upon receipt of a door lock switch lock or unlock signal, will switch the appropriate door lock actuator control circuits to battery positive voltage. The opposing side of the door lock actuators are connected to ground internally within the BCM through the other door lock actuator control circuit and the doors will lock or unlock appropriately.
First thing to do would be check power an ground circuits at the BCM ! Do you have any other systems not working -power windows etc...
The DR/LCK fuse supplies battery positive voltage to the I/P fuse block for the door lock system. The body control module (BCM) supplies and monitors a reference voltage to the door lock switch through the door lock switch lock/unlock signal circuit. The door lock switch also receives a constant ground source. If a door lock switch is placed in the lock position or unlock position, the reference voltage is taken directly to ground and the BCM detects the voltage drop on the signal circuit.
Should have BCM checked for stored DTC'S - diagnostic trouble codes !
Ignition ON, observe the scan tool Driver Door Lock Sw, Psgr Door Lock Sw, Driver Door Unlock Sw and Psgr Door Unlock Sw parameters while using the driver and passenger door lock switches. The parameters should change between Active and Inactive.
If the values does not change between the commanded states, refer to Door Lock Switch Malfunction.
Command the driver door and passenger door lock actuators to LOCK and UNLOCK with the scan tool, the doors should LOCK and UNLOCK when changing between commanded states.
If a door lock actuator does not perform the LOCK and UNLOCK functions, refer to Door Lock Malfunction
all the lights above the dash do not work ?????? DOME light's ??? No light's come on when you open the door or any door ? Wouldn't think all the door ajar switches bad at one time .
The interior lamps consists of two groups, lamps that can not be dimmed and lamps that can be dimmed. This first group consists of lamps that may not be dimmed. This Includes those lamps that may be manually turned on by placing the interior lamp switch to the DOME position, or by opening a door or a compartment:
• Auxiliary dome lamp (SEO, RPO 6C7)
• Dome lamp
• instrument panel (I/P) compartment lamp
• Inside rear view mirror lamps
• I/P courtesy lamps
• Reading lamps
• Rear compartment courtesy lamp
• Sunshade vanity mirror lamps
Battery positive voltage is applied at all times to the DIC/RKE fuse and to the switched side of the BATT RUNDOWN PROTECTION relay in the right I/P junction block. The DIC/RKE fuse supplies battery positive voltage to the coil side of the BATT RUNDOWN PROTECTION relay. When the ignition is turned to the ON position, the body control module (BCM) provides a ground to the Inadvertent relay control circuit. This energizes the BATT RUNDOWN PROTECTION relay and applies battery positive voltage to I/P BRP fuse and to the TRK/ROOF/BRP fuse. Battery positive voltage is applied from the I/P BRP fuse to the I/P courtesy lamps, I/P compartment lamp and to the I/P compartment feed circuit to the BCM. Battery positive voltage is also applied from the TRK/ROOF/BRP fuse to the:
If the BCM receives a door lock or unlock input signal, the BCM will activate the BATT RUNDOWN PROTECTION relay, which provides battery positive voltage to all interior courtesy lamps. When any door is opened, the door jam switch contacts close and the BCM receives a door-open input signal. The BCM then applies a ground to the theater dimming ground control circuit illuminating the courtesy and dome lamps.
After all the doors are closed, the courtesy lamps remain illuminated for approximately 40 seconds. The courtesy lamps will also turn on and remain illuminated for approximately 15 seconds after the ignition key is removed, prior to any door being opened.
When the headlamp switch is placed in the DOME position, the BCM receives a ground signal. The BCM then applies a ground to the theater dimming ground control circuit. This illuminates the dome and roof rail lamps.
The courtesy lamps will normally turn off using the theater dimming feature. The BCM provides a pulse width modulated ground to all courtesy/reading, dome, and inside rear view mirror lamps for the theater dimming feature. The BCM will immediately turn off the courtesy lamps if a door lock command is received with all the doors closed, or if the ignition switch is turned to either the ON or RUN position.
The BCM activates the interior lighting output 15 seconds after receiving the class 2 message "Airbags Deployed" from the sensing and diagnostic module (SDM). The interior lamps remain activated for 25 minutes.
The door ajar switch is part of the lock actuator inside the door !
The keyless entry system consists of the following:
smart entry control(SEC)/timer module
keyless entry remote transmitters
power door lock actuators
body side door power door lock actuator
power door lock switches
door ajar switches
Principles of Operation
All doors can be locked at once by turning the door key lock switch to the locked position. An individual door can be unlocked by moving the door key lock switch to the unlocked position and turning it again within five seconds; all the doors (including the liftgate) will unlock.
The smart lock system is designed to keep the driver from locking his keys in the car. It will lock and then unlock all the doors if the smart entry control(SEC)/timer module detects the following conditions:
The ignition key still in the ignition.
A front door is open.
A door lock switch has been pushed to the lock position.
The panic feature has a duration of 30 seconds from the last time the PANIC button is pressed. When locking the doors from the remote transmitter, the horn chirp/lamp flash feature can be disabled or enabled by holding the LOCK and UNLOCK buttons for two seconds. The hazards will flash three times to confirm that the feature has be enabled or disabled.
The control module probably see's an input that shouldn't be there . lock Switch , door ajar etc... Don't think it has anything to do with the remote . Some part stores have a tester to see if signal from the remote is working . Or the dealer ! Take it an see if your remote is sending a signal without you pressing any buttons .
If it is you need a new one .
Rear Side Door Actuator Control Module
The rear side door actuator control module is capable of on-board diagnostic functions described in On-Board Diagnostic Features . The rear side door actuator control module monitors the door position at all times including during manual operation. After activating the on-board diagnostic modes, loosing battery voltage, or ground to the rear side door actuator control module the Power Sliding Door (PSD) Re-Initialization procedure must be performed in order for the rear side door actuator control module to correctly determine the door position.
Power Sliding Door System Description
The power sliding door system(s) can operate correctly only if the power sliding door is in proper mechanical condition. Any mechanical problems will affect the power sliding door operation and must be repaired before attempting to diagnose the power sliding door system. Manually open and close the power sliding door to determine if the door moves smoothly and without excessive resistance or binding. The power sliding door must also latch and unlatch without the use of excessive force. At any time during power sliding door open or close operation, excessive resistance to the door movement will cause the power sliding door to stop and reverse the direction of travel.
The power sliding door will operate only when the power sliding door on/off switch in the overhead console is in the on position. At anytime during power sliding door operation the on/off switch may be turned to the off position and the system will quit any function in process. The power sliding door will not open unless the transmission shift lever is in the park position and the door is unlocked. When the sliding door security lock is in the locked position the power sliding door will not open from the inside. The power sliding door close function will operate when the vehicle is in gear. The power sliding door module uses the VSS signal to determine if the vehicle is moving during a power sliding door close function. The momentum of the vehicle moving forward adds resistance to the door closing operation. When the rear side door actuator control module determines the vehicle is moving forward while closing the door, current flow through the actuator motor is increased instead of being reversed. The VSS signal circuit is supplied battery positive voltage through a resistor then monitored within the rear side door actuator control module. The VSS signal circuit is then pulsed to ground, or pulled low by the powertrain control module in relation to vehicle speed. The sliding door alarm will sound repeated short tones whenever the power sliding door system is turned on and the door is open while the transmission is out of park.
When the power sliding door system is on and manual operation of the power sliding door is detected the rear side door actuator control module activates the power assist feature. When the power assist is activated the power sliding door will continue to open or close without any further manual effort.
The power sliding doors may be operated using the Remote Keyless Entry System. The keyless entry transmitter will have one OPEN/CLOSE button with a van symbol on it for each power sliding door. The power sliding door ON/OFF switches in the overhead console must be in the ON position in order to operate the power sliding doors using the keyless entry transmitter. When a right hand power sliding door OPEN/CLOSE function is activated using a keyless entry transmitter the exterior lights will flash once indicating the RKE module has received the OPEN/CLOSE command. When activating a left hand power sliding door OPEN/CLOSE function with the keyless entry transmitter the exterior lights will not flash.
On-Board Diagnostic Features
The left and right power sliding door systems operate as independent systems. The on-board diagnostic modes are entered and operate the same in both systems.
The power sliding door systems are capable of the following on-board diagnostic functions:
• Diagnostic Mode 1: An audible signal indicates the diagnostic trouble codes stored by the rear side door actuator control module.
• Diagnostic Mode 2: An audible signal indicates when inputs to the rear side door actuator control module are active.
• Diagnostic Mode 3: Performs an output test of the sliding door unlatch actuator.
Entering On-Board Diagnostics
The on-board diagnostic modes can only be entered in a sequential order from modes 1-3.
• Enter the right power sliding door system on-board diagnostics using the right B-pillar open/close switch and the right on/off switch in the overhead console.
• Enter the left power sliding door system on-board diagnostics using the left B-pillar open/close switch and the left on/off switch in the overhead console.
1. Both power sliding doors must be closed and in the latched position.
2. Place the ignition switch in the OFF position.
3. Place the on/off switch in the overhead console to the OFF position.
4. Press and hold the B-pillar power sliding door open/close switch.
5. While holding the open/close switch, operate the on/off switch through 10 ON and OFF cycles within 10 seconds stopping in the on position.
6. The sliding door alarm will sound 1 long tone indicating diagnostic mode 1 is active.
Diagnostic Mode 1
Upon activating diagnostic mode 1, DTCs will begin to be signaled by the sliding door alarm. The DTCs are 2 digit codes and the codes are represented by the number of buzzes for each digit of the code number. For example a DTC 12 is represented with the following sequence: buzz, pause, buzz, buzz, long pause. Each DTC will be signaled 3 times before proceeding to the next DTC. Refer to Diagnostic Trouble Code (DTC) List . The DTCs will continue to be repeated in this manner until the on-board diagnostics are exited or mode 2 is entered. When exiting the on-board diagnostics all stored DTCs will be erased from the rear side door actuator control module memory.
the alternator will not die in one day unless there is a direct short causing diode or coil winding failure which would give signs of smell, melted wires. Disconnect battery and give full charge. what year is this? while vehicle is running you should be able to briefly disconnect positive battery post connection and vehicle will still run if alternator is good. For a new battery to die in one day, one of two things i think has happened. Either the batt is faulty from supplier,( not likely but i have seen it ) or there is a direct draw or grounding taking place whether its direct in the starter selonoid or a direct draw through accessories. Are you sure all switches are off ? Push switches (on interior lights) nothing like dome lights,delayed lights are staying on! Does vehicle start hard like it almost needs a jump. If it has to be (and it takes time). to find out what is drawing the power ( i am old school) disconnect positive power source on batt. 2) disconnect ignition power source on starter. 3) connect pos batt wire to starter, 4) touch positive cable to positive batt post and look for spark or contact. if this reacts then selonoid or starter motor is shorted drawing the current. Or if you have volt meter and know how to use it, this is good to. If checks good then hook ignition connection back on starter.(disconnect pos terminal on batt prior to re-connect) I think the battery is having the life sucked out of it by a short in the system ( A DRAW ) this could be a quick find or fix or this could take days to track down. alot of variables here to try to explain. but i would seek into the starter first as usually this drains the battery quickly .
use a test light and follow the main supply wires going into the cars cab keep poking thru the insulation with the tester probe at regular intervals until you dont get any power. there might be a fusable link or a maxifuse somewhere blown. check fuse panel for pwoer and check the wires to and from the ignition switch.
Check ALL your connections. Take each Batt terminal off and scrape them or buy a Batt. brush from parts store/cheap 7 bucks. If you can jump it it may be the Batt. has just gone.. Clicking means you have a bad connection or the Batt is shot.