hionnos

I've got a few problems. I started having prob. w/ my left front . it would slip & I'd get a warning on the dash - . Triangle w/ ! inside kept driving it and then the ESP lite appeared. The air susp. deflated except for the l/ rear. I tested the relay w/ a friends tester & it failed so I replaced it with one from born warner. put it in & it wouldn't start, no click at all. put back in the old one & it would start but run for 5 sec. & die. what did I do wrong? A friend told me about an imobilizer .do I have to reset something? Any ideas, anyone?
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