Originally Posted by
onehundred80
What I am getting at is did it act the same then as now except for the sound level? I am suspecting it did.
I am trying to find out if this is a new problem or a noisier old problem.
Have you looked for water in the trunk? The pump module is an integral part of the security system and if water has got into the well were the unit sits under the foam in the trunk you may find that is the problem. Look in the well under the trunk mat, water may be visible down the gap between the foam and the trunk well, use a paper towel and slide it down the crack.
No. The issues are different. Originally it sounded and I couldn't do anything but disconnect the battery to silence it. Now I can unlock and then lock it with the remote to silence it. Also, the unit I replaced was under the windshield wiper cowl, not in the trunk. I will check for water as you suggest though. Thank you. Btw, the unit I replaced was Mercedes part # A 219 820 32 26. It costs about $220.