The best form of teaching will engage the audience, so that's why this kind of active puzzle is absolutely GREAT. I could watch and learn from this kind of seminar all day long. Thank you Duane, for putting the effort in.

One of the best automotive videos I have ever seen on KZfaq. An excellent mechanic and an excellent teacher. Well Done!!!

Thank you for being so thorough and technical yet clear. Your professional expertise is greatly appreciated.

Great video, I love when someone speaks clearly. Simplifying electrical.

I like learning, it makes my customers feel good. Keep it up Duane, great job.

I drive an almost identical minivan ('97 Voyager SE) as the one in this vid. And with the same problem. I was about to take it to the shop for diagnostics- at $80/ hr. for labor. After watching this, I realize that this is probably the fix that is needed. Tomorrow morning, I am going to disconnect the hatch wiring, to see if it's the hatch lock mechanism. If it's not in the hatch, I will just have to go and disconnect the hotwires for each door separately. This video just saved me a bunch of $$!

The problem with mine was a bad key fob. It was apparently sending signals to lock the doors constantly.

Thank you so much for your help with this! My 2015 Honda has been having these problems, and couldn't fathom it being something as simple as a bad ground.

WAVETUBE84 the Liftgate is not showing a voltage drop from 5 v to close to zero just like you said. I also believe that the body control module logic is noticing that discrepancy and since the vehicle speed is above 15 mph the module is interpreting that as not closed and is repeatedly sending impulses to close the tailgate [liftgate] door

The lift gate lock cylinder switch must be partially shorting the 5V from the BCM to ground intermittently. Voltage only drops to 2.2V, but the toggling from 5V-2.2V must be causing the BCM to see the switch activating, thereby causing it to actuate the door locks.

Now that is quality troubleshooting. Good job.

I have a similar problem with my Chevy hhr and at the same time it has problems shifting to next gear and cruise control sometimes work, any idea? Thanks

Nice old video. I came from cloning rke fobs. My mother had a Chrysler version of this van. We got held hostage by that van, a couple times. Had to crawl out of the windows.

On our 2005 Colorado it was a loose door latch .Make sure all door latches are tight.

I have a 98 Dodge Caravan. The door locks go up and down after turning off ignition and exiting car. Any idea what could be causing this problem and how to fix?

The rear door latch maybe loose. If it is able to move enough to open the switch enough to break the contact...the BCM will be triggered. The latch should hold the door firmly closed. Maybe a minor adjustment. Otherwise, it's a bad switch, loose connection, improper ground bonding of the circuit. Inspect the wiring harness routing to see if it is secure to the door and where it passes from the chassis to the door.

Great job, nice video. Thanks

My car is 27 years old and has central door locking as a standard. i installed a remote control which works just fine. but since a half year i already killed two solenoids. those are pretty expensive. and no i am wondering if those are just worn out or if i did something wrong by installing.

Thorough study .... thank you

Wow, fantastic video. N basically the same model car im having the issue with. Thank you Sir

Can you Please tell me how i can fix the same problem on toyota camry 1999 the doors lock and unlock on their own and any time i start the care ?

Absolutely amazing teaching and professional service. Thank you creating such a great video.

all 4 door locks jump up and down when trying to open and go to a locked position then I have to use key to get in drivers side manually ? pain in the ass

May I know what Scan Tool you are using @3:15? Thank you for this great film. I experienced a similar problem yesterday on 2001 Saturn SL2 and very happy that came across your films. I have Innova FixAssist 3160 RS scanner. Can I use it for a similar test performed in this film?

i had the same problem on my jeep liberty kk,i went to jeep they said i had a bad door actuator i replaced that and now its still doing it my dash just chimes and says door doesnt even lock them any ideas?

im new to this but you conect blue yellow and green and where do you put the black ground wire ?

Where is Fuse Box location for a 1989 Dodge Ram B350...thank you

I thought it was a bad wire but now looks like it's the tailgate switch. I'd try running a ground through that connector to trigger the lock to see if it works as expected. that labscope makes the job way easier than using a multi meter though

In my case, it ended up being a relay in the fuse box My original issue was slightly different tho. When i would unlock the door with the key, it would lock and unlock rapidly, at the same time, my wipers did not have any intermediate settings, only the last 2 settings worked (constant on, slow / constant on fast. The last 2 clicks on the wiper switch.). So i started by trying to fix the wiper issues, i replace the "Wiper ON" relay, and the wipers were fixed, but for some reason this also fixed my lock issue, so yay! tl:dr if you are having lock issues, try your relays first, they are only $10-$20 and are very easy to swap, located in the fuse box. in my case it was the "Wiper ON" relay.

I have an 08 Suzuki Forenza. The locks keep going crazy while driving and or while parked. I don't have a scope/scan tool. Any suggestions on trouble shooting it?

What's the sensor reader you're using?

Now this is a good educational video! 🤘🏽🔥

The liftgate circuit is not indicating the full 5volt drop. It drops form 5v to ~2.4v. So the liftgate switch, contacts, or wire connections are not conducting(making contact). Since the erratic lock/unlock symptom disappeared when the liftgate connector/circuit was disconnected...that isolates the problem to it. So(I speculate) that the lift gate switch contacts are bad or not making 100% continuity. Hmmm, it continues intermittently...while driving Maybe the liftgate switch is bouncing?

@mobilemechman You are correct, it was the door lock. Well done, Sir.

Wiring harness leading trigger mechanism that actuates the lift-gate lock is faulty. Insulation could be stripped in a spot causing intermittent grounding giving a false ground signal

i have a ford crown victoria 2002 which has a similar problem , i want you to tell me what may be the problem in it and how to fix it as well. my car all of a sudden has all the lock only lock by remote and dont unlock but by the button they driver side switch isnt workin and the passenger side only unlock . whats the problem in here????

could be the mechanical keylock in the tailgate if there is one. Something inside the lock could be making an intermittent connection, albeit a poor one.

I would say that corrosion from road dirt and water make it into the rear gate and by unplugging the wire the system seems to work properly. I would try and clean the switch if possible and retest ,if not cleanable I would just go ahead and replace the switch.

What if your car is doing this and the interior lights are coming on as well? Plus the auto headlight feature is not working. 2002 Ford Taurus SEL. The alarm will also go off for no reason after its parked and locked with the key fob. What should be checked and in what order?

Well I just watched the video 8 years after it has been posted - however sine the voltage was drawn down on the offending circuit to about 1.5 volts without being activated and returned to 5 volts when unplugged - I'd venture to say that the switch in the rear is partially grounded causing erratic operation of the lock circuit.... So now it's off to watch the 3rd installment...

Can you tell me what scope your using?

It's a Snap-On verus and when you see the price you might change your mind.

I have door ajar on a liberty but in all 4 doors as read by the scanner...Could it be the bcm

Now i know how to pay attention while taking a class to which i wont bother to take a test .

thank you!!

this man is a very smart mechanic he is the best

I have this same problem and it drives me nuts!

Awesome trouble shooting technique and demonstration. Thank You for posting. Now if I had a scope. LOL

@foxdmulder I have been having the same issue I thought it was just me, I've missed a lot of new videos. Wonder what the problem is.

Most likely rear hatch switch. But I would still check the circuit to rear hatch due to, as Duane pointed out, that circuit never voltage dropped close to zero volts. Ensure the circuit itself is ok. If so, replace rear latch

My friends Honda Odyssey did this. They are getting a new car because it got totaled.

Damn I need you here to do my locks. They doing the same thing. And my remote don't lock my doors but it unlocks them. Pain in the ass to go around and lock all doors. But my tail gate door can't be locked without remote.

Good Evening Realfixesrealfast take care and have a great day Realfixesrealfast 👍 Great tutorial thanks 👍 From Nick Ayivor from London England UK 🇬🇧

You are brilliant! You know your electrical ! I have a crown vic that sit parked and locks/unlocks by it self... any ideas?

I sometimes lock my car manually to keep it running and locked but this sometimes throws it off kilter. My locked car kept unlocking by itself and lights were draining my battery. Ugh. I want this auto lock removed and just use my keys.

How did i miss that in auto mechanics school

@happy543210 I would go along with that if the problem persisted when the tailgate lock switch was unplugged. Since it didn't stay shorted, I still think the problem is in the switch. Good thinking, though. I hadn't thought of that.

Very Cool

I know it's on something bit different but maybe someone help me so I don't have bring my 2010 dodge caravan to garage save me money lol.... when I 1st got my van when driver door was opened from inside all doors would unlock now it's switched where it's only passenger door that unlocks all I'm stumped maybe somehow my 2 year old has programmed it like that playing with my key all the time pushing many buttons lol so any help would be much appreciated

@mobilemechman I don't think it's the gate lock. I think it's a broken wire on the harness at the point where the lift gate hinges on the car's body...that's were constant movement (lifting and lowering the gate) will cause the wires to break and either short out on each other or on a body ground.

How would it cost to fix this problem

What causing it to drain the battery

would that body control module cause the headlights to flash when started and when you lock the doors and the back door to lock back imediately?

2:55 "The three wires that correspond to the three grounds going into the BCM" These are not grounds. They are the signals from three of the five switches. Each of those switches has three positions, which can be seen poorly at 6:09. The positions are : Normally open (signal to BCM pulled high to 5V by pull-up resistor in BCM),; and the up and down positions which connect to two different values of resistor to ground, thus pulling down the signal to the BCM to different low voltages, distinguishing up/down (and which switch for the pairs that share a wire) . If the red scope trace is the liftgate lock switch, and disconnecting it solves the problem, then apparently there's either a fault in that switch, or the wiring to that switch, or the mechanism that activates that switch.

PT Cruiser with haunted tailgate. I'm just going to disconnect in. Otherwise, what's the fix? Thought maybe the fault was in the driver's door latch, but I'm over it, unless you have a simple solution. It's an '05 , but has a keylock on the tailgate, so what am I losing? Nice little car, but this has been doing my head in. Cheers, Andy

I think that’s COVID-19 symptoms. Your car has COVID-19

Please help me. my 97 grand caravan has a problem while driving (D). All locks on all doors are frantically unlocking and locking and so is the open door light. but there are no open doors. when I'm stopped at P, N or D. this problem does not occur. What can it be??

@foxdmulder I've been getting that a lot as well.

My '05 Tucson does that but not at certain speeds. Just random sometimes I can hear them clicking in the back. Then sometimes the door lock thingie in the door will stick halfway and I have to manually push the button til it unsticks and clears and it workable with the remote. Then sometimes my remote won't work. And then...sometimes it will just "CLICK" and lock itself and that really sucks when I have just closed the door and the keys are still in the ignition!!!!! GRRRRR Then... my brand new battery went dead 3 times in the past month and I KNOW this is the problem!! There is a short somewhere... So I took it to an electrical shop and the door lock switch thingie has to be shipped from the East Coast to Portland Or and it costs $240. And total cost will be $650. I want to drive the Tuscon into a lake. With ME in it cuz I am such a PUTZ for paying that much!!!!! GRRRRRR Thank you so much for your helpful videos!!! Appreciate it very much.

You are i f love you job i, wish i could be closed. so i could learn and help others.

The lift gate lock?

99% of time with electrical problems are a ground wiring problem, in this case I believe it’s a faulty lock switch on a door, or more than one.

great vid keep em coming

@michaelovitch Michael, my apologies to you. I'm sorry to have disappointed you. Please be assured that I do read all the comments. I also read all the emails I receive every day as well. I only wish I had the time to answer each one directly. My whole reason for doing any of this is to do what I can, to share what I can, so those who want to learn have some real time examples. My "answer" to the comments is not as valuable as the viewers comments. Duane

most of the time the problem is in the outside fuses box the wires comes green

The built in switch in the locking cylinder needs to be swapped.

My car is doing it just sitting there or any time the key is out of the ignition. Killed the battery overnight.

Would love to get my hand on that scope

@spelunkerd your welcome, and thanks for the encouragement

Its a chrysler, of course the BCM is shot, ha ha

The switch ground

This is a thorough video for a mechanic, but what about a Joe Schmo that doesn't have the fancy equipment to hook up to the vehicle?

short in stop light bulbs contact

My guess is that the wiring going to the lift gate is somehow picking up interference or something

I need to borrow 1000 dollars to get my doors windows and locks to be fixed on my ford escape!

good explaination, but my problem is with the remote control, il activate three doors, not the driver s door have two remotes same condition on both. must use key on drivers door to enter car.

Lift gate lock actuator

anybody can answer - my friend has the same issue who is qualified to fix this A- dealer B-dealer body shop c-any body shop- e-any large mechanic shop . we are in houston texas

switch is bad on tail gate internally

I'm going crazy help please I've spent $700 at 2 different places trying to fix this and not fixed. 09 Sonota drivers side door is locking and unlocking 3x by itself if open the door with car in park and engine running well I do a lot of delivers for Doordash so this happens a lot as do not want turn off car everytime I run up food to a house for 20 seconds. Then if turn off the car the car won't crank key won't turn anti theft or something has locked it down now since gotten back from shop it hasn't needed a tow yet as it released when opened drivers door but this sucks after spending so much to fix and it still is happening so now im getting out through Passenger side or turning off car so it won't set the door locks off and on 3x by itself in park engine running and next time turn car off and then try crabk car key won't turn until open door as it released 2x like this but b4 this didn't always work had get tow. 1 place replaced whole ignition another place reset computer but it didn't fix this issue. Of anyone can help or suggest what to do pls let me know. Thanks!

By the data.....the rear switch is the issue.

I have a Trailblazer 2002 in the problem I'm having is with the shifter when you put it in park the door locks do not work but when you going to put it in drive a Lockwood Ematic what could be the problem

@michaelovitch Just be greatful that Dwayne is spending his time helping to educate people for NO return. Most answers will be answered if you CAREFULLY LISTEN

awesome information. thank you

Well, hete we are in vid #2 and to your answer.....'s to vid #1, if I was a Eectrical Mechanic with the guages I wouldn't be in Residential Construction.

@CoolasIce2 tony???? Thenks for the reply though, lol

When my truck does this I wanna hurt myself damn that’s annoying

What the point to make written comments if you never answer to them but only with the video in wich the problem is resolved yet ? Is it just only for the adsense program ?

Has anyone had trouble with subscriptions not showing on their channel, like part one of this. for the past 4 days my channel keeps telling me ''your subscribers have not uploaded any videos lateley''

You probably have water in a molix plug