I have disconnected the alarm box on my 87 300D and my 87 300SDL without any adverse effects. The door switches were bad on both cars which required me to unlock the car from the trunk (which I forgot to do on a regular basis - nothing like a car alarm going off at 5am to upset the neighbors)

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Chris Young

Current cars:
1978 240D 4-spd manual 99k miles
1987 300TD - 132k miles
1987 300SDL - 280k miles.
1996 Subaru Outback - 132k miles
2003 Chevy Silverado Duramax/Allison - 195k miles

"My wife thinks I have a disease..... I think I have just inhaled too much diesel exhaust .... My neighbors think, well, who cares what the neighbors think"