C-Class (W202) 1995-2000: C 200 CDI, C 220 CDI, C 270 CDI, C 180, C 200 K,C 230 K, C 220, C230, C 280

Keyless entry and other power lock issues

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Mar 1, 2010 | 01:51 PM
  #1  
TexFinn's Avatar
Thread Starter
Super Member
 
Joined: Jun 2009
Posts: 506
Likes: 1
From: Argyle, TX
10 Tahoe LT, 07 Silverado Z71, 99 BMW R1100RT
Keyless entry and other power lock issues

I recently bought a 97 C230 and was wondering if you guys could give my any ideas regarding the keyless entry and power lock issues I have with it.

1. The car came with two remotes, but neither one worked. I changed batteries on both and now it seems that at least the other one is sending signal (according to the tester @ AutoZone), but still there is no movement on the locks. Also, the red and green LEDs do not light up at any point.

As I don't have Owner's Manual, I tried synchronizing the working remote according to instructions I found by Googling (press the remote three times, insert key to ignition and turn it to position 2; all within 5 seconds), but still nothing.

I'm thinking it might be something electrical. I didn't see a separate fuse for the system in the fuse box in the engine compartment. Is there another one somewhere else?

2. The power locks work when pressing the button on the dash, but not from the passenger door. If I insert the key to the passenger door and turn, that door will open, but none of the others. Also, I can not lock that door by turning the key in the lock.

On one hand I'm thinking it's vacuum related issue, but on the other hand I'm thinking about electrical issues. Vacuum is probably working as the locks work from the button on the dash and also the rear headrest release works.

Any and all tips, ideas etc. are greatly appreciated.

Thanks!
Reply
Old Mar 6, 2010 | 09:34 PM
  #2  
TexFinn's Avatar
Thread Starter
Super Member
 
Joined: Jun 2009
Posts: 506
Likes: 1
From: Argyle, TX
10 Tahoe LT, 07 Silverado Z71, 99 BMW R1100RT
Found out a couple of days ago that all locks will open if I use the trunk lock. Locking does not work, though.

Got an owners manual and tried synchronizing according to the instructions found there, but still nothing. Still no life in the LED's.
Reply
Old Mar 9, 2010 | 06:58 AM
  #3  
maksi's Avatar
Member
 
Joined: Jul 2009
Posts: 89
Likes: 0
From: philippines
2020 GLC200 (X253) 1995 mb W202 C220, 2008 Mitsubishi Lancer Evolution, 2014 Ford Mustang 5.0
you didn't say if the car runs. in case it does, here is my input:

1. The car came with two remotes, but neither one worked. I changed batteries on both and now it seems that at least the other one is sending signal (according to the tester @ AutoZone), but still there is no movement on the locks. Also, the red and green LEDs do not light up at any point. - probably bad remote trigger. try bringing it to a more qualified technician,

As I don't have Owner's Manual, I tried synchronizing the working remote according to instructions I found by Googling (press the remote three times, insert key to ignition and turn it to position 2; all within 5 seconds), but still nothing. - i tried that a thousand times with mine and a thousand and one times - IT DIDN'T DO SQUAT. forget about it. again, refer to a qualified techinician,

I'm thinking it might be something electrical. I didn't see a separate fuse for the system in the fuse box in the engine compartment. Is there another one somewhere else? - if the car doesn't run. a bad immobiliser unit. immobilser is located on the kick pan under carpet in the passenger side,

2. The power locks work when pressing the button on the dash, but not from the passenger door. - check connections underneath the sidings. If I insert the key to the passenger door and turn, that door will open, but none of the others. - it's only an override to gain access inside the car, it's not centralized. Also, I can not lock that door by turning the key in the lock. - in theory, door should lock but not all doors, since it's not centralized,

good luck dude.
Reply
Old Mar 9, 2010 | 08:32 AM
  #4  
TexFinn's Avatar
Thread Starter
Super Member
 
Joined: Jun 2009
Posts: 506
Likes: 1
From: Argyle, TX
10 Tahoe LT, 07 Silverado Z71, 99 BMW R1100RT
Originally Posted by maksi
you didn't say if the car runs. in case it does, here is my input:

probably bad remote trigger. try bringing it to a more qualified technician,

i tried that a thousand times with mine and a thousand and one times - IT DIDN'T DO SQUAT. forget about it. again, refer to a qualified techinician,

if the car doesn't run. a bad immobiliser unit. immobilser is located on the kick pan under carpet in the passenger side,

check connections underneath the sidings.

it's only an override to gain access inside the car, it's not centralized.

in theory, door should lock but not all doors, since it's not centralized,

good luck dude.
Thanks for the comments.

Here's some additional info:

1. Car runs and drives great, so no issues with the immobilizer.
2. Bad remote trigger? In the remote or somewhere in the car?
3. Bought an Owners Manual and tried directions from there to synchronize. No luck.
4. According to the manual, also the passenger door should lock/unlock the whole car. Just like the trunk.
5. Found out the other day that I can unlock all doors from the trunk lock.

So... I guess I have isolated my problem to maybe two things:

1. IR receiver in the car is not working. Is there a module/brain unit or what ever it might be called somewhere I should maybe swap out?
2. Something wrong with the door actuators so that they are not locking the doors. Or is there a power door lock computer module somewhere that could be partially bad?



Damn, I hate electrical bugs...
Reply
Old Mar 10, 2010 | 05:26 AM
  #5  
maksi's Avatar
Member
 
Joined: Jul 2009
Posts: 89
Likes: 0
From: philippines
2020 GLC200 (X253) 1995 mb W202 C220, 2008 Mitsubishi Lancer Evolution, 2014 Ford Mustang 5.0
bad remote trigger - if you said that you had the remote checked out it works fine, the IR receiver located inside the rear view mirror might be culprit,

Bought an Owners Manual and tried directions from there to synchronize. No luck. - was wondering where you got that?

According to the manual, also the passenger door should lock/unlock the whole car. Just like the trunk. - maybe it works on your model. mine doesn't open all doors, only functions as an access to the car,

Found out the other day that I can unlock all doors from the trunk lock. - how?

thanks and goodluck.
Reply
Old Mar 10, 2010 | 12:19 PM
  #6  
TexFinn's Avatar
Thread Starter
Super Member
 
Joined: Jun 2009
Posts: 506
Likes: 1
From: Argyle, TX
10 Tahoe LT, 07 Silverado Z71, 99 BMW R1100RT
Originally Posted by maksi
bad remote trigger - if you said that you had the remote checked out it works fine, the IR receiver located inside the rear view mirror might be culprit,
I guess I'll need to look into maybe getting another mirror.

Originally Posted by maksi
Bought an Owners Manual and tried directions from there to synchronize. No luck. - was wondering where you got that?
The Owners Manual? Got a set of all books and the leatherette portfolio for a 97 from Ebay.

Originally Posted by maksi
According to the manual, also the passenger door should lock/unlock the whole car. Just like the trunk. - maybe it works on your model. mine doesn't open all doors, only functions as an access to the car,
Yup, that's what the manual says. I would imagine, though, that it's the same for all models with power locks.

Originally Posted by maksi
Found out the other day that I can unlock all doors from the trunk lock. - how?
Turn the key to the left to unlock and to the right to lock. Mine only unlocks, though.

Originally Posted by maksi
goodluck.
Thanks! I definitely need that...
Reply
Old Jun 23, 2016 | 04:04 PM
  #7  
bng1959's Avatar
Junior Member
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 25
Likes: 1
From: Eureka Springs
2017 S550 A217,2006 SL500,2002 CLK430
No Green or Red LED on remote or mirror

My 1997 C280 lock/unlock on both remotes failed. Found this Thread and was disappointed no updates in regard to resolution. Replaced battery's and mirror with no change.

I have enjoyed this site for a few years. Find all types of knowledge and from time to time a smile when I fix a issue with the W202 and W215.

What I have found from this is I need to check the module. We can only use trunk and passenger door key hole to lock/unlock.

Bruce
Reply
Old Jun 27, 2016 | 05:23 PM
  #8  
bng1959's Avatar
Junior Member
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 25
Likes: 1
From: Eureka Springs
2017 S550 A217,2006 SL500,2002 CLK430
Appears replace module is the answe. My post on this subject is closed in my mind. I enjoy reading all this knowledge and will go back to read only mode.
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish

 
story-1

7 Craziest Things AMG Gas Ever Built

 Verdad Gallardo
story-2

New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

 Verdad Gallardo
story-3

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-4

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-5

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-6

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-7

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-8

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-9

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 10:44 PM.

story-0
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish

Slideshow: Six gift ideas your AMG loving dad or grad will cherish.

By | 2026-06-03 17:26:18


VIEW MORE
story-1
7 Craziest Things AMG Gas Ever Built

Slideshow: Sometimes AMG builds fast sedans. Other times, it builds twin-turbo V12 land missiles and six-wheeled off-road monsters.

By Verdad Gallardo | 2026-05-26 17:59:58


VIEW MORE
story-2
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

Slideshow: Mercedes-AMG's new electric GT 4-Door Coupe trades combustion for software, synthetic noise, and more than 1,100 horsepower.

By Verdad Gallardo | 2026-05-20 20:08:15


VIEW MORE
story-3
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-4
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-5
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-6
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-7
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-8
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-9
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE