I just installed a Code alarm CA545 in my wifes new corolla. I know the alarm are crappy, but I got it for free for helping a friend out at his shop. Anyway, it has a channel which says it is for, or can be used for rear defroster. I hooked it up, but when I activate the channel it comes on, and goes right back off. I never hooked up the rear defroster in my years of installing, so I dont know if I am missing a step. The only diagram that the manual had was to switch it to a positive pulse as the alarm outputs negative. Any help would be appreciated.
Do you have a volt meter? It sounds to me that the factory switch is a latched untill power off switch. Seems as though the alarm is only generating a pulse. You need to check the vehicle wire after turning on manually and see if the switch is keeping it latched. If so you will need to duplicate that with the alarm wire. Can that wire of the alarm be programmed for a latched output?
I do have a multi meter, how do I know if it is latched, if you could let me know what I should be looking for when i test it that would be helpful. When I tested the switch before, the wire (black wire I believe) was at 12 and would drop down to around .7 or so I think. I have looked in the book and I dont see any programming options for that channel. Again, thanks for any help you can give me.
When you tested the wire and it went to (.)7volts, did it stay there until you turned the defroster back off? Or did it briefly give you the reading, and then gave you the same brief reading when turning the defrost off?
I am guessing that it remained at .7 anytime the defrost was on. If this is the case, the pulse coming from the alarm is jjust briefly pulsing the defrost.
To trigger your rear defrogger you will need a negative latched output.
Connect this to a black wire found in the middle connector pin #2 under the fuse box.
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