First Alarm, 97 Honda Civic

Yes. When relay coils have the power removed, there's often a spike and this can travel back up the lead to destroy the alarm circuitry. Any low current device i.e. 100+ milliamps. Which is just about every make of alarm. Some people here think it's not needed, the alarm makers should put diodes on the board but I won't take the chance. I always put a diode either in line or across the coil with the band facing the + side (86). Look at the relay diagrams on this site.

This is the alternative. B2D_relay_starter_cut.bmp

So while I'm at it, I was wondering about the the AUX functions on these alarm systems. Would there be a way for it to turn on my Air Condtioner? It seems a bit complicated because of the blower motor which is turned on at variable speeds with a knob on the center console switch. Or I can leave the blower "on" at any speed and just have the AUX switch on the A/C? Just wondering...

So I guess I'll turn this into my progress thread. Here is a picture of the car and it's wiring progress.

Ref; the A/C in theory leaving it on overnight and powering up ALL the ignition loom wires should do it. Otherwise you will have to power up the output from the first position onwards on the blower. Your Momo wheel is on the wrong bloody side.

Haha! only in America

So If I wanted to use AUX 2 to control a relay that turns on the AC, would the relay be like:

85 - AUX 2 from alarm harness

86 - +12v

87 - ground

30 - AC turn on wire

No use this configuration, but see what happens when you turn your AC on, turn off engine then turn it on again, if the AC comes on, just leave it on overnight. The wiring to your relay is completely wrong. B58_1_relay_template.bmp Use the same set-up for a defogger control.

You just proved to me that I know nothing about relays. Haha! I think i'll just leave the AC on during a hot day. So I think I have it all set. Alarm, 530T, a few conveniece features. Going to start mounting everything up this weekend. I'll post more pictures of my progress. So many wires it looks like spaghetti!

Mounting of the alarm unit, and the 530T. Still have to mount the backup battery and relays. Most wire extensions are completed.

What are we looking at? Driver or passenger kick panel?