Push Button Start

[Retnavy]

Okay! I've got a question for all you maintenance types out there.

If the push button fails, how would/do you start the car? If you out in the middle of who knows where and stop to take in the scenic view, or whatever, and the push button fails to start the engine. Everything comes to life, but starter won't crank. What now! What can we do in that kind of a situation to get started and get home?

 

[SHOrod]

Everything comes to life, but starter won't crank.

So you're not really talking about the push button failing then, you're talking about the starter failing. If the button itself failed, nothing would come to life (radio, climate control, navigation, etc.). If the starter fails, it's really no different on this car than any other, you attempt to get to the starter with your umbrella or a large stick and tap it a few times, then try to restart.

If the button fails, and nothing works, but the battery is obviously still fine, then I'd pop the button/panel out of the dash and short across the larger switch terminals (not the terminals for the switch illumination) with something like a screwdriver or watch band with my foot on the brake pedal to get the car to start.

-Rod

 

[cthomas286]

So you're not really talking about the push button failing then, you're talking about the starter failing. If the button itself failed, nothing would come to life (radio, climate control, navigation, etc.). If the starter fails, it's really no different on this car than any other, you attempt to get to the starter with your umbrella or a large stick and tap it a few times, then try to restart.

If the button fails, and nothing works, but the battery is obviously still fine, then I'd pop the button/panel out of the dash and short across the larger switch terminals (not the terminals for the switch illumination) with something like a screwdriver or watch band with my foot on the brake pedal to get the car to start.

-Rod

Also there could also be a problem with wireless fob system. If that is bad then even shorting across the push button will not start it. It has to detect the correct fob inside the car. If this is the case hope you have cell coverage.

 

[SHOrod]

There is a little cubby in the center console to store the fob in the event the battery in the fob is dead or weak. But year, if someone drives over your fob and breaks the transponder, then even the cubby is not likely to work. However that scenario isn't really that much more likely than a standard metal key getting broken or deformed in a way that it no longer fits the ignition cylinder. Realistically even water should not harm the transponder portion of the fob, just the keyless entry and Intelligent Access.

I'm making an assumption here that the transponder is separate from the IA portion, but I guess I don't have the technical drawings to back that assumption up. Since there is a specific cubby to address low/dead fob battery issues though it would seem logical.

-Rod

 

[N8rfastback]

Does there have to be a battery in the FOB for it to work to start the car? I dont think so, Its just like RFID I think. The car "pings" the transponder if you will, and the reflected RF is what tells the car its ok to start, unlock the door, open the trunk, etc...

You only use the battery in the fob if you push a button to unlock the door, open the trunk, roll down the windows. etc.

 

[N8rfastback]

Oh and you cannot short across the pushbutton system to start the car.. I am pretty sure once that button is unplugged from the car you cant do much with the wiring, I think there's more to it than just a momentary push button switch...

 

[RedCandySHO]

If the button, FOB, starter or anything causes my SHO to not start....I dial 1-800 Ford Road Side assistance.....

 

[SHOrod]

The factory service manual shows the start button as a DPST momentary switch with two internal LEDs. One LED is for illumination, the other illuminates in Run. The dual poles are not necessarily for redundancy even though the lines are named "S/S Gnd1", "S/S Gnd2", "S/S 1" and "S/S 2". A person would possibly need two conductive items to short both poles independently. That might be a good little set of jumpers to make up and keep in the glove box....

-Rod

 

[wildosvt]

So you're not really talking about the push button failing then, you're talking about the starter failing. If the button itself failed, nothing would come to life (radio, climate control, navigation, etc.). If the starter fails, it's really no different on this car than any other, you attempt to get to the starter with your umbrella or a large stick and tap it a few times, then try to restart.

If the button fails, and nothing works, but the battery is obviously still fine, then I'd pop the button/panel out of the dash and short across the larger switch terminals (not the terminals for the switch illumination) with something like a screwdriver or watch band with my foot on the brake pedal to get the car to start.

-Rod

Have you seen the push button switch out of the IP? I work where our IP begins life and the wires on it are all tiny. Its all done with relays and what not. I hope that we all never run into that problem..

 

[SHOrod]

Okay, so 5 of the 6 wires are 22 gauge, one is 20 gauge. Interestingly the 20 gauge is for the LED illumination.

Since Post #2 was written before I looked at the service manual, I'll now correct the comment. I would attempt to short switch terminals 1 and 4 (gray/yellow to yellow/orange) and short terminals 3 and 6 (green/white and brown/violet). The trick could be getting the two pairs of wires shorted at the same time. I'm not sure if that would be necessary or not. I'm pretty sure it would still be worth a try given you're in the middle of no where in your scenario and it may be 4 hours before road side assistance would find you.

Considering how small the wires are, there obviously is not much current flowing through them. This switch is likely to be much more reliable than the typical key cylinder and ignition switch in your standard car. I'm not aware of many people that car a spare ignition switch around in their glovebox.

-Rod

 

[Carson Lomax]

Check the brake switch. The ECM needs to see that the brake is depressed before it will close the relay between the battery and starter. The push button just tells the ECM you want to start the car.

Several years ago Ford started "handing over" starting functions from the key cylinder to the ECM in order to offer factory remote start and also for keyless starting systems. On some cars (I think Fusions and maybe 500s) you could just turn the key to "Start" and let go but the engine would continue to crank until it started (ECM controlled cranking). It was no longer required to turn-and-hold the key in the start position until the engine caught. In cases like this and the push button starter, these are just "switches" telling the ECM what you want to do and don't have any real current carrying capacity.

 

[SHOrod]

Yep, One Touch Ignition System (OTIS). The new Taurus with a key as well as several other Fords have that feature now.

And, yes, if the button were to hypothetically fail, one would need to depress the brake pedal before shorting across the push button start switch wires.

-Rod