My 03 Navigator's backup alarm stopped working. When I put it in reverse the alarm sounds for a couple of seconds and the mirrors adjust but the alarm don't go off as I get close to an object. The dealer replaced a module and it worked for two weeks then stopped. Now dealer says sensors went bad also and wants $800.00 to fix. Any ideas???

 

I had an intermmitant issue with mine, then it finally went out. It wound up being a broken wire at the left rear tail light. Up until it finally died, anytime I poked around it would work for a little while. Maybe while changing the module they jostled things a little and got contact with what might be a wire going bad.

 

I changed the battery during the repair and the alarm not working again. I wonder if that caused a problem. I am afraid I'll pay for an expensive repair then find it's a loose wire,