remote wont unlock car unless you point at door

[lodownlv]

2001 clk 320
i have an issue with my key not unlocking the doors unless you point it at the doors IR sensor.
its also real strange because if im in my car and i press unlock it works, its like the range of the remote is failing or the range of the cars antenna?

my first question is where is the antenna for the rf pickup of the alarm. i noticed the antenna on the roof of the car is broken wich ive seen on alot of these cars. is that where it picks up the rf for the alarm?

my second question is where is the rf pickup module?

i checked the remote bat and they are both good.

any sugections?
thanks

[StickyBenz]

Hmm its probably because you have a Low Battery in the Key Remote... Try replacing them!

[lodownlv]

i tested the bats and beleve them to be good wich is what i sad in the posting. i will replace anyway and get back to ya.
thanks

[unitfreebie]

Replacing with a new sealed battery is best... testing is iffy... some testor do not put enough load on the battery.

Testing with a voltmeter without a load is the wrong way to test any battery!!!

Good Luck ..

[charliew]

The proper load for testing a battery with a voltmeter is 1,000 ohms per volt.
Charlie

[Pepper]

Could be the com bar. See this thread.
Help - Smart key barely working after car service - Benzworld.org - Mercedes Benz Discussion Forum

[keyhole]

Anyone know where the antenna receivers are located inside the car that pick up the remote lock/unlock signals? I have seen things that look like miniature mic's, but they may be for the hands-free phone.

btw, I can lock my car with the remote from my upstairs bedroom window - about 20yds from the driveway..

[Pepper]

That's what the com bar (communications bar) is and is for. It receives both the infrared and radio signals. When I had the problem with my remote, I also had a problem with the radio reception. In my car, the com bar is horizontally across the rear of the roof. BTW, it could be that you simply need to upgrade the software for the com bar - shortly after the dealer replaced my com bar, the same problems started again. The dealer upgraded the software and I've had no problems since.

[lodownlv]

replaced my batery same problem why is it when i touch my key to the com bar the antenna at the rear of the car it still dosnt open but when i press unlock on the remote when inside the car it works?

what is the part number for the com bar and replacement procuderue?
thanks

[Pepper]

On my model, there is an I/R pick-up at the door, and the signal is also picked up by the comm bar. If the comm bar is defective, the I/R will only work when the remote is aimed directly at the door pick-up. Don't know the exact procedure or the part number for the comm bar - mine was done under warranty and the work order does not show the part number. As to the procedure, the work order says that the C-pillar trim on both right and left sides were removed, the headliner was removed, and the comm bar unit was replaced.

Hope this helps.