Help! I cannot lock my doors or trunk

[outdoorzgirl]

I have a 1998 SLK. I noticed a red light by the door lock button on the inside of the car. I tried to lock my doors and they would not lock. I am also not able to manually lock the doors from the outside or by use of my remote keychain. I have also noticed the trunk will no longer lock. What could be the problem? Everything else seems to work just fine.

 

[outdoorzgirl]

Okay my husband said that he is able to unlock when he is inside the car, just not from the outside. He also mentioned that the interior light does not come on when the doors are opened but you are able to manually turn the interior light on. He has checked the fuses and they are all okay. What on earth could be wrong?

 

[television]

Its quite possible that water has got into the boot causing the PSE pump and the alarm system to mal function. There are a few mods that can be done to cure the problem.

malcolm

 

[outdoorzgirl]

That is possible . I had to open the trunk the day it broke and it was raining. How could I go about fixing the problem? Any ideas?

 

[SLKBOYO]

I had a similar problem(search slk pse), which turned out to be a faulty PSE unit. Water had travelled down the wiring loom into the unit via a white connector, causing corrosion on the connector pins and damage to the printed circuit board within the PSE. Check all the relevent fuses, the door switchs, battery in key fob, and the white connector, you need to release the connector by slipping the clip over a catch.Surprisingly the interior light worked when the PSE was completly disconnected when the key fob was used to unlock the car, this proved the ccm unit was ok. I ran the car like this for a while until I got it repaired using the key to lock. In my case data was getting to the pse but was not being processed to the ccm, so the ccm always thought the door was indeed closed, so why put the light on! .The alarm was another circuit affected. Mercedes were aware of the water ingress into the pse as in 2002 they rotated the unit 180 degrees ensuring that any water travelling down the wiring loom now drops off on the bend of the loom keeping the connector dry at all times. There is a kit you can purchase through your dealership to extend the wiring and air lines for the central locking , which is a must I would have thought if you intend to buy a new unit at approx £360. Good luck, hope this has been a help to you and any others.

 

[outdoorzgirl]

^^^^ Thank you!! Very informative indeed