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2002 CLK 500 Remote control issue

1K views 13 replies 3 participants last post by  Loosecannon 
#1 ·
Hi,

Long time reader of the forum, but first post :wink

I am having issues with my remote control unlocking my 2002 CLK 500 , the car would unlock fine, but of late I gave to use the metal key to manually unlock the car, the car starts fine, after driving the car for a while, once I stop and lock the car the remote works for up to 10 minutes, and even up to 50 metres away, if I come back in a few hours it doesn't work

After reading some posts on this forum, I have done the following, but I still have the problem, with both my keys

Replaced both remotes with new batteries,

Opened the remotes, cleaned all battery contacts with an eraser

Both have a solid led light

I have checked fuse #8 in the trunk do the car it's fine


Any advise would be greatly appreciated
 
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#2 ·
Welcome - this is the C209 CLK forum, and with a 2002 CLK you have a C208.

You could re-post your question next-door, but as it happens I have the fuse layout for late C208 models and I think that fuse f8 in the trunk fusebox is for the front right seat adjustments, (seat height front, seat fore/aft). Fuse f2 is for the PSE central locking pump.

Your door locks are radio initiated, electrically connected, and pneumatically operated, so your issue could be with the PSE unit in the trunk, or its tubing. Maybe there is a slow leak, or the reservoir is faulty.

Here are some WIS drawings to provide some information on the PSE system which provides pressure & vacuum to the door locks, plus trunk lock and fuel filler cap lock, .

Can we assume that you only have one key?
 

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#3 ·
Hi Keyhole,

Firstly thank you for you detailed reply, I appreciate it :smile

Ok, I thought it might of been a c209... A c208 it is,


Well today the car wouldn't unlock, or start,....after going over the car once I got it running I notice the EC reset button on the climate control stays on when the car has stopped, the key has been removed , even with the car locked, it stays on... Some how I don't think it should....:crying

I have been working out the climate control of late, the previous owner replaced the battery without resetting the climate control, this broke a stepper motor A32m2....once I push the pollen filter button it stops ( will get around to replacing it).. Although I am considering taking these filters out, I don't have allergies , plus it might pump the A/C better for our hot Australian summer...lol

The stereo is standard , I noticed if I'm playing a cd when I stop the car, when I go to drive again the cd goes back to the start,..and each time I get in the car, the stereo has to be turned back on ( if it was on when I left the car )

I'll still search for power leaks over the next few days.. I suspect this could be the problem with the remote locking keys


Thanks again
 
#5 ·
Whoops - my mistake there. We didn't get C209 in the UK until 2003. You can see the difference easily by the headlamp arrangement - C208 has 4 separate headlamps, 209 has a lozenge-shaped design for each side.

In that case you can forget all that stuff about pneumatics failing, as the 209 door locks are totally electric.

Is your car battery in good condition? A dying battery can cause many strange faults.
 
#6 ·
Hi Keyhole*


The battery is only a few months old..


While looking at it today. I turned the climate *control off. Fan off ..*when you turn the key on and start the car the climate *control starts with the fan near high...

Plus if you leave the ec resest on ( climate control button). You can get out of the car. Lock it. And it stays on.. i dont know if it is suppose to do this.. i would think no

Im starting to think battery drain
 
#7 ·
If you press the EC/REST button after shutting off the engine, it goes into REST mode which runs the cabin ventilation fan for up to 30 minutes. The purpose of this is to keep the cabin warm when parked for a brief period of time.
 
#8 ·
Hi,

Thanks for your replies,

I drove to work today, once I got there, I unplugged the passenger side power seat harness ( RH drive car) under the front of the seat , 8 hours later, the remote control opened the car perfectly, I thought I would try to start eliminating things that drain power, I had read on this forum that seat power unit can give problems,


Now I know where the problem is, I have read that you can run the constant power wire into the ignition wire on the seat power unit. I have tried to look for more info on how to do this, but with no luck yet,

If the the seat power module is prone to fault, I don't really see any point in spending money to put another in
 
#9 ·
If the the seat power module is prone to fault, I don't really see any point in spending money to put another in
I'm inclined to agree with you about a 14 y/o car. In fact I would be happy if ALL my seat movements could be done manually, like in the old days.... :)


Actually it might not be the module, but one of the many motors being driven by the module. However, I reckon that you could just find an optimum passenger seat position and then leave it disconnected.
 
#10 ·
Yeah , it could also be a motor, not the module

If it's only a matter of splicing one wire into another, as on other models, I might as well try it


Apparently it's a matter of splicing the constant power wire ( on a 3 pin plug) in to the switch 12v power....

I just need to research which wires, colors etc :nerd
 
#11 ·
These WIS circuit diagrams might help you here. Shown for the driver's side, USA:

a) the seat (and window) control switches are routed to module N69/1
b) the seat control motors are driven from module N32/1.

Wire colours are shown, with abbreviation. BR (brown) is traditionally used for chassis earth.


M27m1 goes to connector 4 - forward/back
M27m2 goes to connector 3 - rear up/down
M27m3 goes to connector 5 - front up/down
M27m4 & m5 go to connector 6 - head restraint & backrest.

So you could try to identify a faulty motor by disconnecting its cable located under the seat.
 

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