don't know if you can help me out I have a 57reg Mondeo estate and when I lock the car the alarm will go off right away all doors are locked and I have tried bridging the wires of the bonnet switch but it still happening please if you have any ideas of what I need to do to fixs this then please say 

thank you for you time

Hi Gary,  you might find more knowledge of the mk3 mondeo on the Talkford.com forum.     Be sure to ask your query in the Mondeo /Mk3 /Security section. 

1 hour ago, Gary bt said:

any ideas of what I need to do to fixs this then please say

Very fortunately cars alarms never go off for no reason. You might not know what the reason is, but it does !

Get yourself a laptop and download FORScan and connect up to the car with a good ELM327(modified) cable. Then you be able to see what it is that is causing the alarm. The normal thing is the bonnet switch followed by one of the 'door ajar' switches sticking, but whatever the reason you should be able to see it using FORScan.

FORScan (free for use on laptops): https://forscan.org/download.html

ELM327(modified) cable £19.95: https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

On 12/2/2022 at 1:43 PM, unofix said:

Very fortunately cars alarms never go off for no reason. You might not know what the reason is, but it does !

Get yourself a laptop and download FORScan and connect up to the car with a good ELM327(modified) cable. Then you be able to see what it is that is causing the alarm. The normal thing is the bonnet switch followed by one of the 'door ajar' switches sticking, but whatever the reason you should be able to see it using FORScan.

FORScan (free for use on laptops): https://forscan.org/download.html

ELM327(modified) cable £19.95: https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

So got the thing you sad to do but can't see where to test the alarms in there any help 

On 12/2/2022 at 1:43 PM, unofix said:

Very fortunately cars alarms never go off for no reason. You might not know what the reason is, but it does !

Get yourself a laptop and download FORScan and connect up to the car with a good ELM327(modified) cable. Then you be able to see what it is that is causing the alarm. The normal thing is the bonnet switch followed by one of the 'door ajar' switches sticking, but whatever the reason you should be able to see it using FORScan.

FORScan (free for use on laptops): https://forscan.org/download.html

ELM327(modified) cable £19.95: https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

 

You have a lot of communication errors, "U" codes. This is data not been sent or received correctly on the Canbus. The one that is most likely causing the Alarm to trigger is the 'Loss of communication with door module'

The problem could be the common problem of water getting in to the Body Control Module. You  need to check the plugs/sockets of the BCM for signs of water ingress and/or corrosion of the tracks of the BCM.

Use FORScan to clear all of the DTC's and see what returns in the next couple of days.