push button start for coyote

[mlewis]

All,

Thinking about added a push button start in addition to the key ignition switch.

Is it is as simple as adding a momentary (normally open) switch in parallel with the momentary portion of the ignition switch ?

Thanks,

[edwardb]

Yes, sort of. Two things come to mind. (1) Normally the momentary start switch would need the proper load rating to handle the draw of the starter solenoid. Some discussion about how much that is, but might be above the average momentary switch. So a relay would probably be warranted. Having said that, for a Coyote setup, the start voltage from the ignition switch is just a sense voltage to the Coyote PCM/PDB. The starter solenoid load is managed by the Coyote PDB and not a concern. So an unqualified yes for a Coyote. (2) The ignition switch is wired to turn off the ACC portion when in START. In the RF harness, that means heater, wipers, radio, gauges are switched off. This to give max battery power while cranking. Would be hard to duplicate that function, although maybe not an issue.

[Just puttering]

Forget the switch at the key, make your push button the only one and place it somewhat hidden and you just added security. I might add some sort of plug and if it ever broke or you dont want to use it just switch the plug to the key.

If you really want to be creative find a two poll push button that kills the second leg when the first is on and you might be able duplicate the key switch. Run the second through the acc of the key switch and you still would need the key to run the car.
Also, if you added the push button and wanted to turn off the acc when cranking (if you are testing or its cold or something), turn the key to start and then push the starter button.

[Joel]

I'd be interested to know if the computer already supports this feature. Most new cars seem to start more from engine management than the key. By that I mean, turn the engine on by just momentarily bumping it into 'start' and the starter continues until the engine turn on, even though you don't have the ignition engaged in 'start', just 'run'.

[Joel]

Apparently there are also a lot of DIY kits for adding push start to just about any ignition. Most of those seem to come with a controller box.

[mlewis]

(1) Normally the momentary start switch would need the proper load rating to handle the draw of the starter solenoid.

Yes, looking at a high volt/amp switch

(2) The ignition switch is wired to turn off the ACC portion when in START. In the RF harness, that means heater, wipers, radio, gauges are switched off. This to give max battery power while cranking. Would be hard to duplicate that function, although maybe not an issue.

If you really want to be creative find a two poll push button that kills the second leg when the first is on and you might be able duplicate the key switch. Run the second through the acc of the key switch and you still would need the key to run the car.
Also, if you added the push button and wanted to turn off the acc when cranking (if you are testing or its cold or something), turn the key to start and then push the starter button

Yes, my plan would be to have the ignition/key turn still in the circuit. The idea is to turn the key to on then push the button to start.

Here's a except from the RF schematic. Any advice on how to tap into the wiring to the key switch to parallel the push switch (NO) ?

ignition schematic.png

[Just puttering]

The key jumps batt to start to energize the start circuit. Put the push button the same, from batt to start should do the same as the key.