door lock vacuum pump???

[mbc220]

I have a 95 c220 and recently I tried to have an alarm installed but they tell me that I have problem with the door locks. I hear the dreaded buzzing noise from the trunk but no hissing when the door locks engage. How do I diagnose the vacuum pump in the trunk and how much does it cost for the part.

[audiophile]

did you have this problem with the locks before the install? its a possibility that they might have fired the PSE.:confused: go back and talk witht the installer. do the locks work if you open with the key at the handle?
if it does work they may have wired something wrong. if it doesn't work then chek the PSE.
good luck;)

[htfan1]

Originally posted by mbc220
I have a 95 c220 and recently I tried to have an alarm installed but they tell me that I have problem with the door locks. I hear the dreaded buzzing noise from the trunk but no hissing when the door locks engage. How do I diagnose the vacuum pump in the trunk and how much does it cost for the part.

These are two different concern:

1) It sounds like your door locks are working...? The vacuum pump noise could be related to a vacuum leak somewhere, but that would not affect the installing of an alarm.

2) What problem did the alarm installer describe? The alarm installer has to know what they're doing (or do some homework) to have the aftermarket automatic door locks work on a Benz.