Hello guys.

I need your experience and help , i´m having some issues with my car. I have a 2002 c230k sportcoupe, it´s a nice car to drive and i love it, but few days ago started with a weird problem... sometimes when a try to open my car with the FOB at distance the car doesn´t react.... letting me to open the car with the IR sensor in the doors... I read a lot on internet, and i know that it could be the Antenna, the fuse 8 in the rear, the central locking, the pump, but here is the problem...

1- My FM receptions its ok, works without any problem.
2- My AM reception doesn´t work at all.
3- My IR lock and unlock works perfectly.
4- I checked the fuse 8 and 9 and they are ok.
5- Sometimes i press from 30 meters my FOB and the RF works and unlock the car, but sometimes happen that after i drove and then i turn off the car, try to lock with the RF and.... doesnt´work at all.. i lock it with the IR and just 12 hours later (in the morning) guess what.... i use the RF and works!!!.
6- Central locking in the dash works perfectly.


Today in the morning i did it and something happened, i unlocked everything but the passenger´s door, I don´t know what happened but it was like this:

1- I pressed the unlock button with the RF
2- All unlocked but not the passenger´s door.
3- I pressed one more time the unlock button and... the passenger´s door opened!


I changed the batteries in my two FOB, checked the 8,9 fuses and i really don´t know what´s going on, i love my car but this is turning me crazy.



Another facts to take into account are:

1- Two or three months ago i installed Xenon aftermarket with Error cancelers, i don´t know if this affects in someway something in the car.

2- Tree times in 6 months it happened that the car started in 3 cylinders, i supposed this because the engine moves too much and has less acceleration, i fix this just turning off and turning on the car.

3- 3 months ago i tinted the rear window, after that i never had any problem with my antenna reception.


I don´t know if could be the cold weather here or maybe the xenon aftermarket that i installed, or the antenna has something, or... wherever.... i read every single thread about this and i can´t solve it.

I would really appreciate your help guys.

 

Either your rear glass needs replacing, or you're suffering from severe electrical gremlins.
Before you replace the glass, check your battery voltage. When at idle, your voltage should be about 13.4-13.6 volts. If not, I would assume it could be the fault of the battery. These cars get real finicky when the battery isn't perfect.

 

Thank´s a lot Alwag for your reply, i though the same as you about the battery, but i wasn´t pretty sure about the voltage, i mean, could it be possible to start the engine and have electrical problems because the voltage is not the approppriate?, i´ll take your advice and i´m gonna check tomorrow the voltage, hope to find that it´s this the cause of all this.

Thank´s again Alwag, tomorrow i´ll let you know about this!

 

It's possible it could be your glass, but unlikely. It is more likely the "antenna amplifier" which is adhered to the top of the glass. It can be replaced separately. You also need to make sure your tint is non metallic or your reception will always be intermittent and questionable.

 

Sedan:

https://mbworld.org/forums/3902226-post8.html

Coupe:

https://mbworld.org/forums/4655785-post45.html

First thing to check is that sticky pad at top centre of the screen has not let go. Give it a hard shove. Often the cause of erratic temp sensitive behaviour.

 

You know something Glyn? i checked the antenna but i didn´t notice about the other component in the left of the rear window, i´ll check it to see if there something wrong.

Yesterday i drove the car but when i turned on the ESP wasn´t working, then after turn off/turn on again and... guess what! the error disappeared.

Also, today i´m gonna buy a voltmeter to check if the battery is ok or not .

 

Thank´s Holmes, and just like Glyn said, i´m gonna check the antenna, but... yesterday it worked without any problem, i´m starting to believe as Alswag said, that the battery has a problem and need to be replaced, today i´ll find it.


Thanks man!


I´ll let you know about my weird issue

 

Check the sticky pad!

 

Alswag i turned on the car and the voltage was 14,33 volts, then i turned off and was 12,57 volts

what are you think about this?

 

I would try and check it 3 times and take the highest 2 and see how far apart they are.

 

Have the battery properly load tested ~ the only way.

 

take a look Glyn

 

Sorry bud ~ my bad. I posted both but forgot you had a Coupe. It's the sedan that generally suffers the sticky pad coming loose.

Check all connections to the glass. Check all other connections & earth points. Check that the amplifier is getting power with a meter.

 

Furthermore, get some electrical contact spray and spray heavily between the glass and the antenna amplifier. This will usually temporarily bridge the contact of old corroded antenna amplifiers. Water leaks into them sometimes for various reasons causing corrosion on the circuit board and the contacts between the antenna and glass to break. If you spray it down with contact cleaning spray and everything magically starts working again for a few minutes, you are looking at a new amplifier. Benz also has a 'repair' antenna amplifier cover that protects any water from getting into it ever again. It should be installed with a new amp.