@@nawrasal-iraqi No

I have not tried to do this on Car Scanner ELM OBD2 app.

@thomasjbaker7688 o app torque não tá disponível a versão do meu celular

@@Jinald92. I can probably reproduce the display on Car Scanner,,, But Car Scanner maybe cannot display the words, just numbers. This would make it hard to understand.

I only started putting these videos here to document my experiments for my own purposes. I forget a lot after I have done something !!

The two are nearly simultaneous. The switch from 2 Hi to A4WD or 4 Hi takes about the same time for both the front acle disconnect and the encoder/shift motor.

If the service 4WD light is on in the instrument panel cluster you can try resetting the control module by removing the #8 ATC fuse in the underhood fuseblock for a minute or so then reinserting it. There is a second fuse for the 4WD in the rear fuseblock under the back seat but that one does not reset anything. That said, if either fuse is bad the system will not work for 4 wheel drive.

@@thomasjbaker7688 Hi Tom: The fuses are all good. There is no warning 4wd light on dash. When I move selector from where it is stuck now, AWD, to 2WD all I get is a click and it then default to 4WD hi. If I switch from 4wd hi to AWD it stays there after its blinking sequence. I just cannot get it to 2wd.

​@@Ed-dr6qc I cannot think of anything that should make a click sound. There are no relays involved. Where does this click sound come from? If the light is on at Auto, and you mive the switch to 2 Hi, the light flashes at 4 Hi?? If yes then I think the switch may be the cause. Some people say to turn the switch back and forth to all positions in an attempt to 'clean' the contacts inside the switch. Key OFF of course.

The drivers (left) side wheel is connected by a CV shaft from wheel to the left "side gear" in the front differential. Opposite that in the front differential is the right "side gear". The right "side gear" is splined to the "intermediate shaft" which runs through a passage in the oil pan. The two "side gears" have two "spider gears" coupling them together. The relationship of this set of gears is best seen in video demostrations of how a differential works. The "imtermediate shaft" exits the right side of the oil pan and enters the disconnect where it is splined to another gear which is seen in this video. It's the gear seen lowest in the video, the gear that I placed the other gear on top of.

So the drivers side (left) wheel is always connected to the differential. Decoupling the right side wheel/axle from the intermediate shaft allows for the intermediate shaft to actually spin 'backwards' as you drive down the road in 2 wheel drive. Allowing the intermediate shaft and related gears and front propshaft (driveshaft) to sort of freewheel a can help a little with fuel economy.

Not chasing anything..Just demonstrating that having the cluster show the "Unknown Driver" message is not a reason for the vehicle (2002 Trail lazer) not to start. I made this vehicle report "Unknown Driver" and it still started just fine.

There was no "fix" because there was no trouble here. I was only showing that the fuel pump relay gets 12 volts from the PCM for a few seconds when the key is turned on. This is to prime the fuel pump.

I have not heard that. Good to hear this video may help. You have me wondering just how fast have I recorded my own fan speed. Mine seldom if ever is commanded on by my PCM.

Well I just checked another video I have here and when I commanded the fan to 100% and held engine rpm close to 2000 I saw 2300 rpm at the fan.

Yes, the sound is loud enough to be heard from the drivers seat even. That is as long as the engine isn't running and the radio isn't cranked up!

That requires a dealership type scantool.

The app seen here is the Android version of Bluetooth Serial Terminal by Kai Morich. I use this app with VeePeak Mini Bluetooth OBD2 adapters. All the commands used to setup the adapter and communicate are contained in the ELM Electronics datasheet for the 327 OBD2 adapter, "ELM327DS.PDF" available for download at SparkFun as well as a number of other sites.

Sorry, I do not know.

That depends on what tools, scanners, meters you have. In this video I show a test meter connected to the BCM terminal that goes to the yellow wire of the Passlock Sensor. When the key turns to the START position the voltage drops and the BCM reads that voltage. That voltage has to match what yhe BCM knows is the right voltage for that vehicle or the security system won't let the vehicle run. What do you need to know?

Brother my chevy trailblazer 2006 the security light doesn't wanna stop and doesn't crank sometimes it crank's for 2 seconds then stop sometimes it can't does the bcm is the issue of my chevy? Also i noticed the lights from inside I can't off whenever i open the door and try to off with the switch itself. My trailblazer is flooded it reaches inside until the center console but my ecu is totally fine

I did a test on my own 2002 TrailBlazer where I was able to operate briefly in 2Lo. It was a fairly sketchy thing to do. If I actually wanted to safely operate in a 2Lo mode I would install a switch to disable my front axle disconnect and select 4Lo mode. Without the front axle locked I would have a viable '2Lo' operation.

Not as far as I know.

Indeed yes, that is what I would expect to find. Not so much a faulty sensor itself, but a loose or dirty connection somewhere in the factory passlock system wiring perhaps. I am not familiar with how aftermarket remotes wire into the Passlock system so I cannot rule out there being an issue there. If an aftermarket system were to be wired in parallel with the factory Passlock sensor there exists the possibility that the aftermarket system could alter the overall resistance placed across the yellow wire from the BCM and the low reference (ground) and that would alter the returned signal voltage which the BCM needs to see. Did that make any sense? The best clue would be to read the code(s) from the BCM at a time when the security light has lit up. The specific alpha-numeric code should give the data needed to further clarify what is happening.

For some reason I cannot see your second reply here, but I did get it in an email from KZbin?? So anyway, yes, those 3 codes help. The first code B2961 is likely the result of starting the truck with the aftermarket remote system. That system spoofs the Passlock sensor but likely does not spoof the "key in ignition" switch so the BCM sees the right security signals but does not see a key in ignition sensor signal. I would guess this is normal for an aftermarket remote start and not a problem. The other DTC codes, B2960 and P1631 are the result of an incorrect Passlock Data value (yellow wire voltage) seen by the BCM. The B2960 code tells us that the Passlock Data signal voltage (yellow wire) is within the operating range for the system but does not match the value stored in the BCM for your truck. This likely means that your 5 volt power and grounds to the Passlock sensor are good. But the voltage seen on the yellow wire after the key is turned to the CRANK position doesn't match what the BCM wants to see. What it doesn't tell us is if that yellow wire voltage is too high or too low. Does your scantool display live data for the BCM or is it only a code reader type device? My next step would be to observe the Passlock Data voltage after starting with the remote (engine running). Then compare the same Passlock Data voltage after it fails to start with the key. If a scantool that can read live data is not available these measurements can be made with a decent multimeter. I can provide details on how this is done and I think I have a video of this.

@@thomasjbaker7688 I was able to get live data from my scan tool. It shows 5v at all times when starting the engine using the car alarm remote start feature, and 1.039v when attempting to crank the engine with the key (unsuccessful, triggers passlock deterrent). (It looks like the youtube filter robot deleted my previous reply possibly because I included a link to a discussion thread that describes someone with the exact same 3 error codes who also has an aftermarket car alarm remote start system. In that case, he found that the installer had bad workmanship when he installed the bypass resistor causing intermittent fluctuating voltage with the wire hanging by a strand, and he cleaned it up by replacing with a new heavier duty resistor with better soldering. I doubt that's my issue because my car alarm installer is very experienced and generally makes good quality connections.)

​​​@@ddbear8786 Well your voltage when using the remote start sort of undermines my understanding of how they work! I cannot think of any way to use a bypass resistor and NOT drop the voltage. Plus, the BCM should not accept a sensor voltage of 5 as a valid code. I would expect the highest acceptable voltage to be about 4.8 volts. Your 1.039 voltage corresponds to what the BCM would classify as a "Passlock Code 2". The Passlock Code 2 voltage range is between 0.67 and 1.08 volts. As the DTC code reported, that is a valid code but evidently is not the one the BCM expects. I was hoping we would see what voltage the remote start bypass resistor presented for comparison purposes. If we had seen a proper voltage drop when the truck started with the remote we would then know what the "right" code/voltage is.

​@@ddbear8786 So just to clarify, When reading live data with the scantool, using the key, when the key is turned to RUN (not started) the live data should show a Passlock Code of 12 and a voltage at or very near 5 volts. When the key is turned to the START position the voltage and the Passlock Code should drop. Is this what you observed? And when using the remote start, the voltage remains at or very near 5 and the Passlock Code at 12?

This sensor is required for all electro-viscous fan clutch systems. It cannot be eliminated as long as an electro-viscous fan clutch is used.

@@kevinalbers1084 Just showing a part of how the device works inside.

Não é um adaptador, é um app.

I use a bluetooth OBD2 adapter as the interface between my android phone and the vehicle data network. The brand Inuse most often is a Veepeak Mini Bluetooth OBDII available on Amazon for about $15 US dollars.

Is there something specific you didn't understand in the written description?

Pretty much, yes. Each gear is splined to a shaft, either the intermediate shaft or the CV axle shaft. Each gear has teeth on the outside diameters and these teeth get coupled together by the collar that is moved by the shift fork driven by the actuator. The actuator (at least an original one) has a coil spring inside so if the external teeth of the gears are not aligned and the shift collar cannot easily slide over the mismatched gears then the coil spring of the actuator compresses allowing the actuator to go full travel. When there is a little movement of either of the 2 gears and the teeth move into alignment the coil spring will move the shift fork and collar coupling the gears together.

Yes, the intermediate shaft is nearly always spinning. Generally the front driveshaft spins due to friction inside the transfer case clutch pack and the rotation of the drivers side cv axle. It may surprise a lot of people that most often, while rolling down the highway the intermediate shaft is actually spinning backwards. When cold at 65 mph mine spins about 1200 rpm backwards. This drops to about 700 or so once all the fluids are fully warmed up. Don't discount the possibilty of a driveshaft being out of balance. It happens.

Aapke dimag par hai

You might need to push in where the actuator pushes in, using something like a long screwdriver, and slowly turn the passenger wheel at the same time so the two gears get lined up. If you can push all the way in where the actuator pushes, and spin the front passenger wheel, with neither the drivers side wheel nor the front propshaft (between the transfer case and front differential) turns then it is possible that this disconnect has something broken inside. But it could also be something broken on the front differentail.

@@thomasjbaker7688 Thanks for responding! I took that disconnect off and opened it and it's fine. I guessing it's the diff that's messed up but it's new it was replaced last month. But the transfer case and front driveshaft lock up so It almost has to be the diff

@@IkeCoblentz Maybe drain the front differential fluid and check for metals? Are all the splines OK on the CV shafts and intermediate shaft?

@@thomasjbaker7688 Yes the splines look fine. Ok I'll look for metal

Enable background data and enable app sleep mode in mobile settings

@@Tajbabamh Thanks, but the app isn't listed in the background data section.