16 Explorer XLT Push Button Start Problems!!

[emerica243]

hey all,

So I recently purchased a 16 XLT with 32K miles on it. About a month into purchase now i'm already experiencing issues with the Push Button Start. I've had push button vehicles before so I know most of the possibilities for troubleshooting this. However I'm stuck and am definitely looking for some answers or things i'm missing.

The symptoms are intermittent and the car will not crank or start. There is no sound at all. I will hold the brake, and press the button, however it only goes into the Accessory Power mode as if i'm NOT pressing the brake. I can press it find times (the brake is rock hard at this point, and nothin happens). Eventually so far it will crank and start. I have found no pattern. At first I thought bad brake switch, like the vehicles not registering the brake is being depressed. However i'm guessing that's NOT the cause since the push button light goes green when i press it in thus seeing its registering.

Again this only happens sometimes, sometimes first thing in the morning, sometimes after driving it around all day and getting back in. I do not think its a low keyfob battery issue because im not getting "key fob not detected" error. I also put the keyfob in the slot to see if that made a difference and the first time I did it whether it was a coincidence or not it cranked for a second then stopped(which was a first), the second press of the button the engine started like normal. This might of all been a coincidence as again eventually when im in this weird state after pressing the button enough times it does start as expected.

Im not sure what else to look for based on the weird behavior im seeing.

Here are the only codes that are being thrown by the computer.

PCM DTC P1921 - Transmission Range Signal

PAM DTC U0402 - Invalid data received from TCM

ABS DTC U0401 - Invalid Data Received from ECM/PCM

PSCM DTC U0401 - Invalid Data Received from ECM/PCM

GPSM DTC U0422 - Invalid Data Received from body control module

 

[peterk9]

Welcome to the Forum.
I'm afraid I can't help you with the codes but there are a few members that can. Since you haven't mentioned it I'm guessing that you are not getting a warning about the transmission not being in 'Park' This was an issue with some Explorer so I thought I'd just mention it. It is an issue with the shifter.
From all the codes you've posted, I think your problem is likely elsewhere. Good luck.

Peter

 

[emerica243]

Thanks for the reply Peter. Nope I saw that on a different thread. Doesnt seem to be my issue

 

[sheltonfilms]

This one is your issue: PCM DTC P1921 - Transmission Range Signal

Transmission range also known as neutral safety switch is what tells your engine computer what gear you are in. The car will only start in park or neutral and if the signal isn't reading one of those two then your vehicle will fail to start.

Based on the fact it cranked for a little then stopped makes it sound like you have a loose connections somewhere between the PCM and the TRS (transmission range sensor). Could be corrosion, spread terminal, terminal not seated, broken wire, etc.

 

[sheltonfilms]

Look at C168 which is the lever lock connector on the front of the transmission. Inspect for terminals properly seated and signs of corrosion.

 

[sheltonfilms]

Sounds like you have a pretty good scanner so pull up PCM and read the "TR_CRANK" PID. This is the "TR Input Allowing Engine Start" parameter and obviously if this isn't correct then it won't start.

I will pull the PIDs tonight for all the TR switches and get a baseline of what each should read for each gear (PRNDL) so you can compare to yours to see which switch circuit is giving the issue.

 

[emerica243]

Sounds like you have a pretty good scanner so pull up PCM and read the "TR_CRANK" PID. This is the "TR Input Allowing Engine Start" parameter and obviously if this isn't correct then it won't start.

I will pull the PIDs tonight for all the TR switches and get a baseline of what each should read for each gear (PRNDL) so you can compare to yours to see which switch circuit is giving the issue.

Sheltonfilms thank you so much for this information! I will perform the testing tonight, thanks again!

 

[sheltonfilms]

Alright got you some information. This should help us figure out if it is bad sensor/circuitry or possibly bad alignment of the shifter cable (if values seem offset).

Here is what everything should be for each gear. The in betweens are the high points of the detents between gears.

 

[sheltonfilms]

Get a chance to look at it?

 

[emerica243]

Are u stalking me? I literally just came up from doing it LOL.

I havent Experienced the problem for the past 2 days. And I'm assuming I need to capture this data when I'm in state of it not wanting to crank and start for me? But regardless here is the data I captured below.

Also before I did press the button for it to start, the TR crank pid was saying "yes". I'm also assuming when it's going to be problematic , it will say "no"?

Park

Reverse

Neutral

Drive

Sport

 

[sheltonfilms]

Yeah when it won’t start it should be “No” when it’s in park.

 

[emerica243]

After clearing the engine codes and inserting my obd2 adapter Everytime before I drove for 3 weeks it hasn't happened. Of course after I stop checking for a week it finally happened again today when I didn't have the adapter in ready for it. Took about 20 button presses to finally start.

 

[peterk9]

Did you get any kind of warranty with the purchase?

Peter

 

[emerica243]

Did you get any kind of warranty with the purchase?

Peter

It's about to hit it's 36,000 period limit. However what concerns me is it's so sporadic and non reproducible on demand that the dealer won't be able to do anything about it. I would also guess based on the facts it's probably electrical related and I doubt this will be the last of any future problems

 

[jmr061]

Get it in so they have it documented. Even if they can't figure it out, it will be documented should it occur after the 3/36 is up which may help you get it covered after that.

 

[sheltonfilms]

Also take a video of it when it does happen.

 

[emerica243]

bringing this back....I was actually able to capture with forscan the working sensor data vs when it wouldnt start. Also, i can confirm when it decides to not start sometimes, if i wiggle the shifter then try again it usually resolves. So does this mean its a switch inside the shifter assembly? Or does the Transmission Range Sensor on the side of the tranny need replaced?

Here is data when it successfully started.

Here is data when it would NOT start

 

[peterk9]

This is purely a guess but I would think that if it was a shifter switch issue that you would get the "Shift to Park" error.

Peter

 

[Napalm]

well initially I would say if you wiggle the shifter and it starts that's a likely culprit - and it's an easier to fix item. BUT I know that's not always the case.

Based on your other data it looks good - but what concerns me is how sporadic it is. SO I'm going to suggest something completely different, well OK slightly different.

Since your first trouble codes come from multiple modules - I think you are havings Comms errors. This is a rare occurrence in a CAN buss car but it does happen. And often repeated comms errors throw another code that points to this. Most common issue is actually a weak battery. Think of it this way you're starting up - there is a sequence of events that occur (you even hear some of them) and as the various modules wake up - if the battery voltage wavers too much (dips below 9 let's say for a number) then some modules will disconnect mid sequence. This causes comms errors and if they are significant enough they will bring on other faults. Not just stopping a start process - but it might cause other check engine lights. But I don't see you reporting other issues or a CEL.

Do you get a CEL that lingers? I guess I would suggest you check your battery capacity, or quality before going too much further. Weak batteries bring on all sorts of electrical gremlins that might not be real.

 

[emerica243]

well initially I would say if you wiggle the shifter and it starts that's a likely culprit - and it's an easier to fix item. BUT I know that's not always the case.

Based on your other data it looks good - but what concerns me is how sporadic it is. SO I'm going to suggest something completely different, well OK slightly different.

Since your first trouble codes come from multiple modules - I think you are havings Comms errors. This is a rare occurrence in a CAN buss car but it does happen. And often repeated comms errors throw another code that points to this. Most common issue is actually a weak battery. Think of it this way you're starting up - there is a sequence of events that occur (you even hear some of them) and as the various modules wake up - if the battery voltage wavers too much (dips below 9 let's say for a number) then some modules will disconnect mid sequence. This causes comms errors and if they are significant enough they will bring on other faults. Not just stopping a start process - but it might cause other check engine lights. But I don't see you reporting other issues or a CEL.

Do you get a CEL that lingers? I guess I would suggest you check your battery capacity, or quality before going too much further. Weak batteries bring on all sorts of electrical gremlins that might not be real.

That all sounds very logical. I will say i have not personally monitored the battery during idle, cranking or after sitting for a while other wise. Also I have never had a CEL light. I will state the facts below...


1. The non start scenario was very sporadic. Sometimes it could happen 3-4 times a day. Sometimes once a week. This is with the car being started\driven atleast twice a day. Sometimes 15-20 times a week.

2. It started to be come common where it would happen atleast once or twice a week. Then it stopped for like 3 months straight. Now recently it happened maybe once, a week ago and nothing since.

3. I can press the Run-engine button multiple times without it starting. I can wiggle the shifter once and it has started right away the next button press. Ive tested this twice so far.

4. I can check battery levels to rule this out. But i see no trend of the car sitting for a while, with a theory that battery levels are lower then normal, and that next start up is why it fails to start. It was all very random, sometimes not

5. I can also check with Forscan if theres any other Errors reporting in the modules of the car.

Thanks for the help...