Won’t start when pressing clutch

[SheepDog]

Thanks Bruce, that will be the last resort if the switches I change for the clutch NSS’s don’t fix the issue. Both of them were only about 45$ by Motorcraft. I find it hard to believe that I have a wiring issue or short for that matter. Car is garaged most of the time in a rodent & pest free environment. After that I will check the starter to make sure the wiring is good and that it’s not loose from the bolts backing themselves out from vibrations. Had that happen on my fox body 1 time. I tightened it up and she fired right up. The instrument panel says for me to press the clutch to start even though I have my foot down on it already. I checked the rubber stoppers on the pedals for all the switches and they’re in excellent condition. So thinking & hoping 1 of the switches is bad.

The problem is far more likely to be a switch, than a wiring issue. You may be able to disconnect the clutch switch and jumper the correct pins on the connector. Once you have a wiring diagram of course.

Sponsored

 

[luca1290]

Before throwing parts at it, find a way so you can be able to read the PIDs of the ECM.
There are various PIDs to monitor and one will tell you the conditions for which the starting of the engine is disallowed.

I read you did troubleshooting on older cars so you are mechanically inclined but on these newer models you must take a different approach. Not that mechanical knowledge isn't valuable, it is, but you must have a way to diagnose the system otherwise you will be wasting time and money.
There is probably not going to be a flashy DTC but by monitoring the system you will be able to better understand it. Forscan and a supported interface are as expensive as the switches you ordered.

 

[Jon 5.0 2015GT]

I don’t have a manual so I’m not familiar with how it’s all wired, but is it possible your tint guys got the solution on some of the wiring (or somewhere else that is connected to the clutch to start wiring) and caused a short somewhere? That would be my first guess if it was working fine until they got their hands on it

It happened before they worked on it. They wanted to move it into position for the guy to start working on the car. I’m thinking the guy either put his foot down too hard on the clutch or his foot slipped off the pedal and popped the switch internally. Because when I went into the car to try and start it my foot almost slipped off the pedal also. Floor was wet with soap because they washing a car where it happened.

 

[Jon 5.0 2015GT]

The problem is far more likely to be a switch, than a wiring issue. You may be able to disconnect the clutch switch and jumper the correct pins on the connector. Once you have a wiring diagram of course.

I tried that but these new Mustangs have 2 switches and the 2nd. One is at the top of the clutch pedal. Hard to do that one. Use to do that with my ‘93.

 

[Jon 5.0 2015GT]

Before throwing parts at it, find a way so you can be able to read the PIDs of the ECM.
There are various PIDs to monitor and one will tell you the conditions for which the starting of the engine is disallowed.

I read you did troubleshooting on older cars so you are mechanically inclined but on these newer models you must take a different approach. Not that mechanical knowledge isn't valuable, it is, but you must have a way to diagnose the system otherwise you will be wasting time and money.
There is probably not going to be a flashy DTC but by monitoring the system you will be able to better understand it. Forscan and a supported interface are as expensive as the switches you ordered.

I’ll go that route after I install the switches I ordered already.

 

[Johnny Rockit]

It happened before they worked on it. They wanted to move it into position for the guy to start working on the car. I’m thinking the guy either put his foot down too hard on the clutch or his foot slipped off the pedal and popped the switch internally. Because when I went into the car to try and start it my foot almost slipped off the pedal also. Floor was wet with soap because they washing a car where it happened.

I have had my wet foot slip off of clutch pedals before. The pain returns just thinking about it. Call and ask the guy how his shin is feeling and you may have your answer.

 

[Jon 5.0 2015GT]

I have had my wet foot slip off of clutch pedals before. The pain returns just thinking about it. Call and ask the guy how his shin is feeling and you may have your answer.

Oh man, I can imagine. My knees aren’t the best either. 1 wrong hit in the right place I’m like family guy.

 

[Johnny Rockit]

Oh man, I can imagine. My knees aren’t the best either. 1 wrong hit in the right place I’m like family guy.

I had done it in my 71 Mustang a couple of times. Once in my 69 GTO, and too many times in the dump truck I drove when necessary. Thought my leg was broken each time with the dump truck. Lol

 

[Jon 5.0 2015GT]

I had done it in my 71 Mustang a couple of times. Once in my 69 GTO, and too many times in the dump truck I drove when necessary. Thought my leg was broken each time with the dump truck. Lol

Yup, I feel your pain man.

 

[Jon 5.0 2015GT]

Good morning all, I fixed my car. Was the switch behind the clutch all along. Got a test light out and grounded it to a nut under the dash(No not myself). Stuck the tip into one side of the plug to the switch it had power. Put the tip of the test light on the other wire no power. Took the switch out and opened it. Cleaned the inside connections with a fine 1500 sand paper. Pulled the plunger out it has fine teeth so you give it a nice pull put it back together installed in the car. Noticed that when I put the test light back to check the power and pressed the plunger now both wires didn’t have power. Car started right up. So if anyone has this issue do what I did. Thanks to everyone how gave me some insight.

 

[TonyNJ]

I try again and nothing still until I slam my foot down on the brake pedal and the starter kicked in. That’s right I said brake pedal.

This exact thing happened to me today. I google, "GT350 press clutch to start engine not working"

Your original post popped up, and I didn't even read past "That's right I said brake pedal".... ran out to the car, and it fired right up. I just hadn't been pressing hard enough.

 

[Cobra Jet]

Good morning all, I fixed my car. Was the switch behind the clutch all along. Got a test light out and grounded it to a nut under the dash(No not myself). Stuck the tip into one side of the plug to the switch it had power. Put the tip of the test light on the other wire no power. Took the switch out and opened it. Cleaned the inside connections with a fine 1500 sand paper. Pulled the plunger out it has fine teeth so you give it a nice pull put it back together installed in the car. Noticed that when I put the test light back to check the power and pressed the plunger now both wires didn’t have power. Car started right up. So if anyone has this issue do what I did. Thanks to everyone how gave me some insight.

And if it’s not the clutch pedal switch, then it could also be a missing or deteriorated clutch bumper stop.

See this below thread which contains many images, DIY and the recently released official NHTSA docs near end of thread. Even though Ford states in the docs it affects 2015's clutch pedal bumper AND brake pedal bumper, , there's many threads on here where members have posted other model years where the problem exists.

https://www.mustang6g.com/forums/threads/brake-light-switch-near-pedal-failure.122100/

 

[IPOGT]

This might sound out there but how old is the battery? There are lots of relays in this car that depend on power to engage pre start.

 

[wingnutt]

can I get in line for this one…lol

First time it happened to me about three weeks ago, but fired on the third attempt. I considered that a nothing and hoped it would go away.

then last week it did it again, I was in the middle of pulling the car out to pop start, and on a fluke tried one more time…she fired right up. Replaced the clutch switch and all was well for about a week.

Third time was yesterday at DFW airport and did everything I could to include disconnecting the battery. Finally gave up and was calling AAA, and in the middle of the call tried “one more time” and she fired.

I am putting her in the shop tomorrow and inspecting the starter

 

[Johnny Rockit]

Has anyone tried holding the start button in and gone through the motions with the brake and or clutch pedals? Curious.

Sponsored