2015 fiesta electrical issues no crank no fuel pump

[Fuelsmoke1]

Hey gang. Need some help before I haul to the dealer.
I bought this 2015 fiesta not running. Its a 1.6L 5 speed manual car. I was told it was running and driving and then just wouldn't start one day. They tried a lot of redneckery and I don't really know exactly what they did do. They did have a locksmith come program a new key because they thought it had a key immobilizer issue. When I got it when key ON nothing lit up in dash. After testing all fuses under hood and in car, found 15A ignition fuse popped in the inside fuse block. Now I have dash function and things are happening. Problem is, no fuel pump when key on, no crank.
So battery and connections are good. Grounds on engine and car are good. Starter will crank the engine if jumped from underneath.
When I turn key to start it says push brake and clutch. I push only brake and not clutch I don't get another message. A relay in the inner fuse panel clicks when I try to engage starter with key. So I think there's a problem between brake and clutch switches. I checked clutch switch, no power to either side, it may just connect ground but I'm not sure at this point. But to eliminate the clutch switch I unplugged it and put jumper in. Still no crank. Ignition switch is putting out signal to start. Not sure it's getting beyond the fuse panel inside or perhaps the PCM itself.
I replaced a fuse and relay in the outer panel, forgot the numbers but are apparently common failure points with these cars. Didn't help my situation.
So at this point, I am not sure what to do. A question I have, if immobilizer is the issue, how could I verify that? I get no fuel pump when key is turned on, and no crank at all. Will immobilizer make that happen or is there something else I should be looking at?
Another thing, it has code for throttle body unit and throttle pedal and coolant temp high. But it's cold.
I usually work on older cars, Ive dealt with enough electronics over the years as a diesel tech and on my own stuff but I'm just not sure what or how to look at this security system. I suspect it may be at least part of the problem??
I'm going to go hug my 55 Ford customline and see if I can get some clarity 😂
Sorry for the long drawn out post, hoping to clear up the first 50 questions I'd get about checking common things.

 

[Handy Andy]

As things may go - in the former Manual cars I've owned - the START switch - the one you press the clutch down all the way to engage - grounds to frame, but if you have no power, then a MAIN relay or the wire that routes to the STARTER relay to GROUND that wire - would show 12 to power the coil and 0V when the pedal is all the way to the floor and the switch is grounding that wire. So one wire would have 12V battery, while the other is left to 0V - so when the switch shorts that completes the circuit and the relay makes the solenoid and start move.

So you just have to retrace back to the starter relay - now I'm not sure but have you inspected the steering wheel and tumbler assembly? The thing uses a "lockout" that lets you twist the key all the way to start ONCE - then locks out any further attempts until you twist the key all the way to off.

This "lockout" may provide a clue as to you may have a relay in the steering column behind the clock-spring and switch assemblies - it rests back there as a means to force the starter solenoid to engage when it's circuit is completed to ground. Else that start relay is back at the main fuse panel in the engine compartment - but the European ones have the relay nestled in the steering column behind the wheel, switch and clock-spring.

 

[Fuelsmoke1]

Thanks for the reply. I didn't know about a relay behind the steering wheel. Great engineering there 😂. I do get the start signal off the ignition switch every time I hit it. I do think there may be a problem with brake and clutch pedal switches. If I don't touch pedals and try to start, center display says push brake and clutch to start. If I push brake that message doesn't pop up. But it doesn't seem to care if I push clutch or not. Also concerning is the lack of fuel pump. I feel like I have one common enemy causing all of this together but I'm not sure. More testing. All I can do is prove it out.

 

[Fuelsmoke1]

As I dig into this,I have another issue that may be the cause of all of this. When I turn key on, display says engine malfunction. I was clearing it and ignoring it. I checked with my scanner and it says throttle pedal is issue. I checked live data and it thinks throttle pedal is at 99.3% no matter the pedal position. I removed pedal/sensor and tested it, it's not changing ohms when pedal is moved. Safe to say it needs a new pedal assembly. Also it claims to have issues with throttle body unit itself. I'm going to get the new pedal first and see if anything changes. It could be that when the pedal was failing it threw a code for the throttle body unit because they were out of sync so to speak.
I will keep plugging away at this rig. We'll get to the bottom of this thing yet!

 

[Handy Andy]

It may be why it won't start, but would still let it crank and crank...

The throttle body doesn't give a resistive reading - it gives - sends, a signal of output to tell the PCM it's position and compares it to the accelerators own position

There is a thread or two about the throttle body - see if a search on this sites forums can can offer some help!