Hello forum,
when I try to unlock my car using the master or spare key in either door my alarm kicks on and immobilizes the starter, everything else electrical in the car is perfect, Has anyone experienced similar problem?

 

Does the alarm go off as soon as you turn the key in the lock or not until you actually open the door?

 

The alarm goes off immediately after inserting the key and turning

 

There is a small switch on the end of each door lock barrel and they have been known to go faulty and cause various locking and alarm problems, courtesy light door awitches are another possibility close each one by hand and make sure the courtesy lights go out.

 

steve2006,
Do you know if this switch replaceable by its self? or is the switch integrated into the lock?

 

IIRC the switch is held to the barrel by a crosshead screw but before replacing it I would try some electrical contact cleaner spray on it, I don't know what you have in the USA but we have a product called Servisol Switch Cleaner in the UK.
You will need to remove the inner door trim but there is a tutorial on www.lexls.com for this,

 

My 93 does the same thing. As soon as you unlock the driverside door the alarm goes off. BUT what I have found out is that if I unlock the passenger side it wont go off. I dont have time to investigate on mine, so I've just been unlocking the passenger side first. Kinda sucks but the wife is with me all the time anyway, so its a good excuse for me to open her door for her.

 

Steve2006,

when I google "servisol" I only get the UK websites, We have some silmilar alternates here in the U.S., I had come across another (electrical component) forum where half the people praised WD40 and the other half didnt, My thought is I will look for something specifically made for the electrical industry.
Just a thought: could the cleaner be effective spraying the cleaner through the pinhole straw into the keyhole? Thanks everyone for your help. I will post my results later.

 

So I drenched the inside of the keyhole switch with the electrical contact cleaner using the supplied pinpoint nozzle, 6 months with no sudden alarm triggering.

 

Thanks for the update... good to know what works. What cleaner did you end up using?

 

Whatever anyone uses, do NOT use WD40. It doesn't dry up and it collects more dust on it and causes a whole lot more problems. Use electrical connection cleaner.

 

Legender,
I used NAPA/CRC QD (quick drying) contact cleaner

 

 

That's great... I've already got that in the garage. Gives me something to do tonight on a few cars.

 

Sorry guys missed replies on this thread.
That's the same stuff as we use here in the UK for switch/contact cleaner.
The actual switch is clipped onto the end of the lock barrel and secured by thin tape around the plastic, cut the tape off and then gently unclip the switch from the barrel.
The wiring loom from the switch has a connector on the end which mates with the socket attached to the door panel so no cutting or jointing required should the switch need replacing.