Land Rover Repair: AMR 6428 - Hazard lights on/off, land rover discovery, inertia switch

Question
John,

I have a 97 Land Rover Discovery. I recently started having issues with my Hazard lights coming on by themselves after hitting bumps in the road. I followed the sound of what sounded like a relay popping on and off traced it to the green box on the passenger side of the vehicle with the part number of AMR 6428. I found that when i turn the vehicle off, remove the key and unplug the gray plug from the bottom of the AMR 6428 box then turn the vehicle back on the hazards go off. I also noted that when this is happening and while the gray plug is disconnected my key FOB does not work.

Is this problem coming from the AMR 6428 box or further up the electrical system? If its coming from the box where can i find a replacement?

Thank you for your help.
Craig

Answer
Hi Craig,

my first thought about your problem was that it could be the inertia switch or perhaps the theft alarm unit.  Both the hazard lights and key fob are linked to the theft alarm unit. You mention the hazards come on after hitting bumps on the road - inertia switch?  

If it is the theft alarm unit, perhaps a door is detected as open or the hood is not shut properly. Perhaps the door or hood sensor is faulted (corrosion).

It could even be the alarm unit itself.  Water leakage in the footwells is a common problem and with water comes corrosion.  Perhaps the unit has to be replaced.  You could remove it, open it and see if corrosion is the cause.

Where to find this unit:  ebay (new/used), www.car-parts.com (salavage)

Atlantic British: http://www.roverparts.com  

Best of luck,
JohnMc