I am trying to set up a remote start for my 99 Tahoe. I have it mostly figured out and am stuck on one last part. I need to make a circuit that controls a Latching relay with a single momentary push button. I want it to work like an impulse relay, but don't want to fork out $25 for each relay. The relays could either be single coil (polarity change) or dual-coil (separate signals) I believe a 555 timer or a decade counter would work to control the relay, but I am not sure how to hook one up to the circuit. Thanks.

Also, a alternate action push button wont work in this case because the circuit is getting multiple pulses from different switches, including a remote control keyfob output. I used on a bypass circuit I made to complement the circuit I am working on, but wont work for the ignition switch. I will post my initial schematics later if needed for explanation.

 

I am trying to set up a remote start for my 99 Tahoe. I have it mostly figured out and am stuck on one last part. I need to make a circuit that controls a Latching relay with a single momentary push button. I want it to work like an impulse relay, but don't want to fork out $25 for each relay. The relays could either be single coil (polarity change) or dual-coil (separate signals) I believe a 555 timer or a decade counter would work to control the relay, but I am not sure how to hook one up to the circuit. Thanks.

Also, a alternate action push button wont work in this case because the circuit is getting multiple pulses from different switches, including a remote control keyfob output. I used on a bypass circuit I made to complement the circuit I am working on, but wont work for the ignition switch. I will post my initial schematics later if needed for explanation.

Simpest method would be to use a DPDT monetary action, center off toggle switch with spring return to center position toggle switch (sounds complicated but it's an available switch). Wire a single coil latching relay's coil terminals to the two common switch terminals. Wire your 12vdc and ground to two of the normally open terminals and finally install two wires in a X pattern between the opposite normally open and normally closed contacts.

Lefty

 

That would work, but the circuit has to use momentary buttons that are already installed. Plus, I would like to control this with my remote using only one button. Now if that was a relay and not a switch, that would be perfect.

 

Is there an ic that could control a dual-coil latching relay, like a flip-flop or something like that. On the first pulse the chip sends a signal to one bank. On the next pulse it sends it to another. Then back to the first.

If I have to I will go with regular relays and a few AND gates to replace the latching gates, but for power consumption and layout issues, the latching relays would work better in this situation.