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Help fixing a Code Alarm security system

My Code Alarm car security system just died. I can still lock all doors

with the keyless remote but, the remote can't be used to unlock the doors. I can hear a click noise from under the dash (drivers side) but,

it won't unlock the doors. I tried using a spare set of keyless remotes

but still same result. At this time entry is only gained by using the key in the door. When parking the truck, usually the doors automatically unlock when turning the ignition off, now the doors remain locked. You can still hear the weak click noise under the dash when you turn off the ignition. But, you must manually unlock the door to get out.

I bought the car used and it had an aftermarket security system install

in it already. No alarm, just a keyless entry system and an ignition switch cut out and a red led flashing light on the dash.

Can anyone offer me any tips/suggestions on how to fix this?

Reply to
umpqua123
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A very good site to help is

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. Not sure what typeof vehicle you have so no one can give you the correct info. Many carshave a dedicated line for the locking action and a second line for theunlocking action. When the line recieves a momentary ground, the doorslock or unlock. It is possible that the joint has come loose. So youwould have to look at the code alarm box under the dash and followwhere the unlock wire goes and check the connection. The wires shouldbe labeled on the side of the case on the code alarm to where they go.If you find this wire, you can touch it with a ground and it shouldunlock that will tell you everything in the car is working. and perhapsthe code alarm module is bad. Chryslers and some other vehicles use the same wire for locking and unlocking. It works off of resistance. If you touch the wire with something like 250 ohms, it locks and with 800 ohms, it unlocks...so if that is the case one of the resistors is bad.

I would post your question at the12volt.com and be sure to provide the make and model of vehicle.

Reply to
komobu

Thanks for the advice. the12volt.com is an awesome site!

BTW. It's a 96 Toyota T100 2dr truck with manual locks and aftermarket actuators installed.

Reply to
umpqua123

My first inclination is that the installer used a relay set to operate the actuators, and a contact in it has failed. The unlock wire could have an open anywhere between the alarm module and the relay set as well. Finally, it's not impossible to fathom that both actuators failed at nearly the same time. They are typically pieces of crap. Look at the price for a set of 4 new aftermarket actuators and you will understand how junky they must be.

Toyota MDT in MO

Reply to
Comboverfish

You were right! I opened up the unlock door relay and found an eroded contact that still clicked for a momentary contact but insufficient to signal the actuators to unlock the door. I found a new relay at a car stereo/alarm place for $3 and all is well. Thanks for your help.

Reply to
umpqua123

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