Altenator engages intermmitenly when running. RPM guage,radion, door locks etc disengage, battery sometimes drains

Try new starter or even try bridging a screwdriver to engage the starter manually that will tell u if its starter or something else

There is either a short in the receiver logic board for the remote, its wires or a relay chattering in the fuse box...Pull the door lock relay in the fuse box to prevent the battery from being drained and begin troubleshooting.

This problem can be caused by a few things, it could be the rear door lock switch or lock module located under the dash or last the rear door actuator.

You say that all door lock and unlock on there on, this tells me it most likely has a module problem or wiring to the rear door is bad.
The first thing i would do would be to remove the rear door panels and check wiring to switches and actuator, then follow wiring from inside the rear hatch to where in goes through the body. the wiring most times breaks at that point where the wiring is bent over from opening and closing rear door ,

Locate the wiring going into door or doors. sometimes the wiring only goes into one door but then sometimes in goes into both doors, check the wiring closely . it may be covered in a rubber boot . if it is covered you will need to slide boot back to check wiring.

Good day. hope this is helpful.

I have a 2007 GMC Yukon and all of the guages (speed, oil, battery, etc.) recently stopped working for no apparent reason. The backlight still works but the guages do not. Could this be something as simple as a fuse? What should I do?

FRONT DOOR TRIM PANEL - REMOVAL
Release door latch and open door.
Roll window down.
Remove window crank Window Crank - Typical , if equipped.
Remove screws attaching trim panel to door Door Trim Panel and Trim Panel Screw
CAUTION: Do not forcibly pull trim panel from door, damage to trim panel may occur.

Simultaneously lift upward and outward to release retainer steps from inner door panel Trim Panel Retainer
Disengage inside handle linkage rod from inside handle.
Disconnect speaker harness wire connector Speaker And Power Mirror Connector
Disengage power mirror wire connector, if equipped (driver's side only) Speaker And Power Mirror Connector
Disengage clips attaching power window/lock switch panel to door trim panel. Disengage wire connector from switch panel, if equipped Power Door Lock/Window Connector
Separate door trim panel from vehicle.
INSTALLATION
Position trim panel at door.
Engage wire connector for window/lock switch panel, if equipped. Engage clips attaching power window/lock switch panel to door trim panel.
Engage power mirror wire connector, if equipped.
Connect speaker harness wire connector.
Engage inside handle linkage rod to inside handle.
Align trim panel retainer steps with inner door panel and slide trim panel into place.
Install screws attaching trim panel to door.
Install window crank, if equipped.

Hope helped with this; remember rated this help. Good luck.

use agood size wire or small cable and run from large post on back of alternator to hot post(positive)of battery ,this will do the same thing sometimes they put ome parts that just get buy to do the job,this will do the job if not replace alternator

had some help here ,everything is pointing to the altenator .Sorry to say after you have changed it twice but i think you have been unlucky and replaced the unit with one with the same fault ---was it a new one or scrapyard ?? start engine and then hold rpm at 1500/2000rpm and disconnect battery if engine continues to run then altenator is charging ,now turn everything electrical on and see if engine continues to run ,if it does then altenator is ok ¿¿¿¿sort of ??.Right now stop engine .Leave overnight and see if it starts (battery disconnected) if engine starts ok then it could be one of two faults,firstly a diode is faulty in the altenator ??or a DISCHARGE like a boot light on ??big amp in the boot for music left on? anything stupid in fact .Quick one here is if after following my advice then not sure ,disconnect altenator and leave battery connected ,if it then goes flat then it something on in the car with a drain of more than 21watts .Divide volts into watts gives you the amperage being drawn.If it starts then its the diode pack in the altenator.Best of british with it .

i had the same problem with my truck, eventually it wouldnt start, im not sure thought cuz you got a veedub check you ignition control module

sounds like electrical problem check battery connections,altenator output, fuses,connectors and wiring in that order sometimes that is caused from low voltage on system thats the reason to check battery and altenator voltages hope this helps

Same thing happened to my '89 Dynasty. Turns out the security system was engaged and this stops the motor from running; therefore. a thief cannot drive away with the car! The system is set by using the power locks or an autolock fob, but not by locking manually. Disconnecting the battery will also engage the security system. To disengage, close the driver or passenger (front) door and turn the key in the lock.