Door lock actuator problem -locking unlocking randomly
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
Door lock actuator problem -locking unlocking randomly
I posted this in the Electronics section without success...hopefully someone here may have an idea...
I pulled in to a parking lot stall last night, shut the car off and within seconds, the door lock actuators began unlocking the doors 4-5 times, then the driver side window wound down. When I got home and pulled into the garage and shut the car off, it happened again. This time, the door actuators kept going like 25 times.
What is this?
I pulled in to a parking lot stall last night, shut the car off and within seconds, the door lock actuators began unlocking the doors 4-5 times, then the driver side window wound down. When I got home and pulled into the garage and shut the car off, it happened again. This time, the door actuators kept going like 25 times.
What is this?
Last edited by RA40; May 10, 2015 at 10:44 AM. Reason: descriptive title
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
Lexus was of little help...do these service writers have any clue? "I don't know....you should bring it in."
Called my Toyota guy and he was far more helpful. However, he did comment this was not common but had heard that this has occured with Camrys and Avalons most often with an after-market security system. His advice, check the relay at the driver door.
My first thought was the multi-plex communication system and I think that is $$$ to replace.
Called my Toyota guy and he was far more helpful. However, he did comment this was not common but had heard that this has occured with Camrys and Avalons most often with an after-market security system. His advice, check the relay at the driver door.
My first thought was the multi-plex communication system and I think that is $$$ to replace.
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
I'm very pleased so far with the treatment at Cerritos Lexus. Made an appointment last night and although the gal told me no loaner cars were available, when the service writer finished up I did get one. So I'm in an '03 ES300. Although newer, I'd take the LS in a heartbeat.
Anyway, the service guy calls back and is talking to my wife and she starts coughing/choking. I'm thinking door CPU, multi-communication CPU...and $1K+. She hands me the phone and our writer tells me that the driver side door lock cylinder is the culprit. I'm thinking, no big deal...sure. He tells me the price, $477
He also comments there may be some other issues like possibly the master switch on the driver door but it seems unlikely. His service technician is 99% it is just the cylinder at fault. I hope so, anything else is eating into my wheel $$.
What sucks is that due to this weekend I have an extended wait so turn-around is not expected till Wed but most likely Thursday.
My advice, use your remote to unlock/lock the door. I don't like a mass of things on my key chain so I only carry the car key and my house key. Thus I am constantly using the cylinder mechanically and all those electrical contacts may not like that. (My presumption)
Anyway, the service guy calls back and is talking to my wife and she starts coughing/choking. I'm thinking door CPU, multi-communication CPU...and $1K+. She hands me the phone and our writer tells me that the driver side door lock cylinder is the culprit. I'm thinking, no big deal...sure. He tells me the price, $477
He also comments there may be some other issues like possibly the master switch on the driver door but it seems unlikely. His service technician is 99% it is just the cylinder at fault. I hope so, anything else is eating into my wheel $$.
What sucks is that due to this weekend I have an extended wait so turn-around is not expected till Wed but most likely Thursday.
My advice, use your remote to unlock/lock the door. I don't like a mass of things on my key chain so I only carry the car key and my house key. Thus I am constantly using the cylinder mechanically and all those electrical contacts may not like that. (My presumption)
Driver
Joined: Apr 2007
Posts: 171
Likes: 0
From: ct
95 Ls, Door Locks Acting Up.
1995 LS 180,000 Miles
For the past couple of days my door locks have been acting up
. They act up mostly when the car is park, but also they act up when I’m driving. Basically this is the issue: When the car is park, the door lock start locking and unlocking and the headlight and rear light go on and off. I tried disconnecting the battery overnight, it seemed to work for about a day but the next day it started again. I thought maybe my battery might be going bad but no, the battery is still good. An auto part worker said I could be having trouble with the factory alarm. For the past couple of days I’ve been leaving the battery disconnected because the locks and light will out go on/off all night; draining the battery. Does any one have any suggestions as to what’s wrong? I do not want to take it to the dealership 
$$$$$$. Thanks in advance.
For the past couple of days my door locks have been acting up
. They act up mostly when the car is park, but also they act up when I’m driving. Basically this is the issue: When the car is park, the door lock start locking and unlocking and the headlight and rear light go on and off. I tried disconnecting the battery overnight, it seemed to work for about a day but the next day it started again. I thought maybe my battery might be going bad but no, the battery is still good. An auto part worker said I could be having trouble with the factory alarm. For the past couple of days I’ve been leaving the battery disconnected because the locks and light will out go on/off all night; draining the battery. Does any one have any suggestions as to what’s wrong? I do not want to take it to the dealership $$$$$$. Thanks in advance.
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
I've got a thread about this here. The drivers door key cylinder has a worn contact that is shorting out. I don't believe they sell the internal switch so you will have to buy the whole key cylinder and have it keyed to your current keys. It's not a cheap fix BTW.
When I looked at mine, the electrical switch is not robust for continuous manual key use...remote opening-closing is preferred.
When I looked at mine, the electrical switch is not robust for continuous manual key use...remote opening-closing is preferred.
Driver
Joined: Apr 2007
Posts: 171
Likes: 0
From: ct
Hey Thanxxx for you input RA40. Read your previous post on this issued. Most often than not, I would lock/unlock the door manually with the door switch 
. For the past couple of days I have been locking/unlocking the doors strictly with the remote key . To my surprise the problem has stopped, for now 
. Furthermore, one of the rear actuator had not worked for more than a year and now all of the sudden it seems to work 
. If this problem is fixed, I just saved some $$$$$$$ . Thanxxxx BRO. 
. For the past couple of days I have been locking/unlocking the doors strictly with the remote key . To my surprise the problem has stopped, for now . Furthermore, one of the rear actuator had not worked for more than a year and now all of the sudden it seems to work . If this problem is fixed, I just saved some $$$$$$$ . Thanxxxx BRO.
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
Glad to hear. What happens is the contact through wear smears metal across the path so it leads to arcing. The plastic insulator is pretty soft so it allows the metal particles to embed in it. Fortunately, it doesn't occur often.
What happens is the contact through wear smears metal across the path so it leads to arcing. The plastic insulator is pretty soft so it allows the metal particles to embed in it. Fortunately, it doesn't occur often.
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Driver School Candidate
Joined: Jun 2010
Posts: 12
Likes: 0
From: CA
When I hit the remote unlock, I can hear the doors trying to unlock several times, but nothing actually unlocks! It works fine when I unlock using the button on the driver's side door, and when I manually unlock by inserting the key into the drivers side door.
It seems like I have have the opposite issue.. I have almost always used the remote key.
Any ideas on what to check first?
It seems like I have have the opposite issue.. I have almost always used the remote key.
Any ideas on what to check first?
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Driver School Candidate
Joined: Oct 2013
Posts: 26
Likes: 1
From: CA.
Yes yes (adding this on, a couple years after last post on this thread, ha) But all the same /same bizarre problem! that totally confuses everybody!.. mechanics and Lexus owners alike, ---> Until you read here on ClubLexus! (yeaay) It's the.. (what did RA40 say up there?)
the Driver's side (whole Key cylinder)! That is the answer I am gleaning here! emailin my mechanic guy!
the Driver's side (whole Key cylinder)! That is the answer I am gleaning here! emailin my mechanic guy!
Lead Lap
Joined: Jan 2007
Posts: 683
Likes: 3
From: UK
Yes yes (adding this on, a couple years after last post on this thread, ha) But all the same /same bizarre problem! that totally confuses everybody!.. mechanics and Lexus owners alike, ---> Until you read here on ClubLexus! (yeaay) It's the.. (what did RA40 say up there?)
the Driver's side (whole Key cylinder)! That is the answer I am gleaning here! emailin my mechanic guy!
the Driver's side (whole Key cylinder)! That is the answer I am gleaning here! emailin my mechanic guy!
If you just want the switch PM me and I'll post you one over from my breaker.
Last edited by steve2006; Dec 12, 2013 at 01:01 PM.
Driver School Candidate
Joined: Oct 2013
Posts: 26
Likes: 1
From: CA.
Hi steve2006 -Glad I just happened to see that you replied! Because after my last post yesterday, my mechanic guy then wasnt sure that I needed to replace the whole key cylinder. since I hear it's somewhere around $500?
So if we can just fix whatever connection problem is happening that when I unlock the door makes the window go down! =P
Is it just (because) the key cylinder is worn out? SO: If we put in a new key cylinder
---> do you think it's very likely that will stop the window from triggering to go down? Because at the bottom line that window going down by itself is what we're really trying to get to the bottom of-
He asked (if I can find out on ClubLexus here) if there is a way that he can test (I think what you were saying, about a switch) What is the procedure to test the Key cylinder switch for the driver's side door. Do you know? He said if he can try that we might not have to buy a whole key cylinder.
Answers here very much appreciated! ~
So if we can just fix whatever connection problem is happening that when I unlock the door makes the window go down! =P
Is it just (because) the key cylinder is worn out? SO: If we put in a new key cylinder
---> do you think it's very likely that will stop the window from triggering to go down? Because at the bottom line that window going down by itself is what we're really trying to get to the bottom of-
He asked (if I can find out on ClubLexus here) if there is a way that he can test (I think what you were saying, about a switch) What is the procedure to test the Key cylinder switch for the driver's side door. Do you know? He said if he can try that we might not have to buy a whole key cylinder.
Answers here very much appreciated! ~
Thread Starter
Joined: May 2003
Posts: 20,929
Likes: 517
From: California
Call the dealer and see if the key cylinder electronics are available separately. Getting the whole cylinder involves a re-key and that is ~$75. The electronics are removable so you might even hit up the junk yards for one.
Driver School Candidate
Joined: Oct 2013
Posts: 26
Likes: 1
From: CA.
Hey Mike /RA40 thanks for your reply! This is what I'm endin up doin on it- (RA40 I know you already know all this -But for anyone else to see in the future) ---Put in a new Driver's side door Lock motor /aka accuator (about $500.) Now she's headed over to the Lexus Dealership next, +they'll put in a new Key cylinder in my door, and then they gotta "code it" meaning make it fit my key I already have. The new key cylinder and to code it to my keys part + installation at the Dealership, will be total (about/under $400.) Also- thanks RA40 for the tip that I could go to find it in a junk yard. So I think this should do it (to fix the bizarre issue how unlocking the driver's side door the window goes down!) That's been annoying. yeah this one even had a few mechanics stumped, ha
Driver School Candidate
Joined: Oct 2013
Posts: 26
Likes: 1
From: CA.
*Also Hey RA40! -Nice pic of your car /I really like! I'm just about a month new to this awesome ClubLexus site. Can you tell me: am I able to attach one of my car pics to my name too?? where do I go /how do I do that? ~eagre to represent on here Love your pic every time I see it, good taste.
Love your pic every time I see it, good taste.
Driver School Candidate
Joined: Jun 2011
Posts: 7
Likes: 0
From: oh
doors lock and windows roll down without being instructed
Hi steve2006 -Glad I just happened to see that you replied! Because after my last post yesterday, my mechanic guy then wasnt sure that I needed to replace the whole key cylinder. since I hear it's somewhere around $500?
So if we can just fix whatever connection problem is happening that when I unlock the door makes the window go down! =P
Is it just (because) the key cylinder is worn out? SO: If we put in a new key cylinder
---> do you think it's very likely that will stop the window from triggering to go down? Because at the bottom line that window going down by itself is what we're really trying to get to the bottom of-
He asked (if I can find out on ClubLexus here) if there is a way that he can test (I think what you were saying, about a switch) What is the procedure to test the Key cylinder switch for the driver's side door. Do you know? He said if he can try that we might not have to buy a whole key cylinder.
Answers here very much appreciated! ~
So if we can just fix whatever connection problem is happening that when I unlock the door makes the window go down! =P
Is it just (because) the key cylinder is worn out? SO: If we put in a new key cylinder
---> do you think it's very likely that will stop the window from triggering to go down? Because at the bottom line that window going down by itself is what we're really trying to get to the bottom of-
He asked (if I can find out on ClubLexus here) if there is a way that he can test (I think what you were saying, about a switch) What is the procedure to test the Key cylinder switch for the driver's side door. Do you know? He said if he can try that we might not have to buy a whole key cylinder.
Answers here very much appreciated! ~
Last edited by bonobob; Dec 16, 2013 at 12:21 PM. Reason: spelling