Alarm issue anti theft issue

petronic

Junior Member
Messages
151
#1
Did ask before for some advice and got some. When I unlock my car place the key in the ignition sometimes the car & padlock wont go out. When this happens the car wont start. Lock it walk away and perhaps next time it will work sometimes it does sometimes not. Stop the car in a car park go shopping and the same occurs again or it may not as if it has a mind of its own. Tried resetting everything same thing its luck dip and has refused to start in a garage!!!!

So any help advice appreciated checkwed batteries in keys ok checked Tracker no problems so something to do with the ignition? please help as I am going mad and looking at trading my car in for a Smart Car!!!! help suggestions please.

How is the Car & Padlock connected to the system anti theft? advice please
 
Messages
26,721
#2
It's the CODE system.

There is an antenna around the ignition switch that sends a signal. That causes a transponder chip in the key to return a signal. The ECU analyses that signal. If it decides it comes from an approved key, permission to start is granted and off you you. If it doesn't get a signal or the wrong signal you get the lock symbol.

Couple of points:
1) The CODE system has NOTHING AT ALL to do with locking and unlocking of doors or armin / disarming the alarm
2) The battery in the key is ONLY for sending the signal to lock / unlock the car and arm / disarm the alarm.
3) The transponder chip in the key is powered only by induction with the signal sent from the antenna around the ignition.

Two possible issues spring to mind
1) (Most likely) The connection to the antenna is worn or loose. If the antenna can't send its signal, the transponder if the key will never reply, and no permission will be granted. This has been seen before.
2) The transponder chip in the key has to be quite close to the antenna. The glue that holds it in place in the key is known to fail (they often drop out when people change the batteries), so it may have come loose (does your key rattle)

You can check the connection to the antenna:
https://www.eurospares.co.uk/parts/maserati/4200-coupe-2003/electrical-ignition/immobilizer-20556
Parts 1 and 3

Take your key apart CAREFULLY and see if the transponder chip is loose. It looks like a small black piece of plastic and should be glued at the front of the key where the blade is.

Have fun!

C
 

allandwf

Centenary Club
Messages
7,159
#3
You could try using the spare key, if you have one, for a while. That would help narrow down which part is the issue.