I went to pick up my kid from a game at school tonight. The car was turned off with the park lights on while I waited. Now the car wont start and the alarm wont stop. It was close to midnight so I disco'd the battery and left the car in the student parking lot. Pretty aggravating and embarrassing night.

So hopefully there's a "quick fix" for this. My driver side lock has been stuck at an angle for some time now, so I can only lock & unlock the doors from the passenger door or the inside, so it's rarely locked. I've read a few post but still not clear on what to do. Will disconnecting the alarm alone fix it? If there's a post with pics or if anyone can help I'd appreciate it. Gotta get Oldirty off school grounds ASAP. Thanks!

ON that car, the factory alarm has NOTHING to do with the car starting or running.

How about the battery?

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Thanks doc, but now I'm even more confused. The battery is fine as far as I know. All power is working including the headlight flashing while the alarm is going. I did try to jump it last night but nothing.

So in thr early w124 there is no immobilizer? That would be quite a coincident to have the battery drain and the alarm malfunction at the same time if there's no relation. Does this mean I can disable the alarm, jump or swap the battery, and get Oldirty home?

Yep. No immobilzer.

Disconnect module under passenger footwell. Its hidden under a black plastic cover. Just pull the connectors out of it (Becker unit) and it'll be disconnected. Then get her home.

Remember NO "jump starting" from another vehicle or you'll severely threaten the OVP relay's life. If you don't own a portable battery, now's the time -- they are invaluable for all cars, but especially on A w124 with an OVP relay. There are a number of MB warnings about this if you do a search. I usually keep the portable battery in the trunk anyway as I never have to worry about a dead battery again.

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Does it crank?

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Ps2cho, I think this is the first time I've heard not to jump w/another car, thanks but too late. A portable charger is definitly in my future.
I did locate & disco the alarm module but now the battery is dead. No crank at all today and it was trying to turn last night.
A jump with another car did get it going for a minute then died again. Twice. I pulled the battery & will have it tested/charged in the morning. I have a spare OVP I'll throw in too.
Thanks!

The Oldirtybastard's home. This morning after an hour of charging, Autozone determined it to be a bad battery. It's a Bosch from PepBoys with a 36 month warranty that I bought in August of 2010, so I took it to PepBoys.
About 2 hours past between Autozone & PepBoys and the battery was DOA. After a half hour of charging, Pepboys determined the battery is good with another 24 months of life, even though 2 tests later showed the battery slowly losing charge. The manager would not (said he could not) honor the warranty without a bad battery reading. So they charged it another 15 minutes, a 20 minute drive to the car, swapped the OVP, installed the battery, the car started right up and made it home.
That was about 2 hours ago and the car still starts with no issues. We'll see what happens in the morning.
I think I'll leave the alarm disabled for now and plan on replacing the battery. I thought Bosch would be a good battery since there a ton of Bosch parts in the car. Or could Autozone just want to sell me a new Battery. Or does Pepboys know the battery is no good and just doesn't want to honor the warranty? Hopefully it's not an alternator issue since this happened out of the blue.
Thanks for your help and following the saga!

Started right up this morning. Surprised but very happy!