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-   -   Car Fails to start! Parking sensor?? (https://www.ft86club.com/forums/showthread.php?t=139525)

Relogical 03-23-2020 12:52 PM
Car Fails to start! Parking sensor??
 
Car:
- 2013 Scion FRS (Automatic)

Battery:
- Replaced less than a year ago

Codes:
- P0700
- P0851

Replacements attempted:
- Switched out Park/Neutral Sensor

My vehicle is having trouble starting. When turning the vehicle, it will not do anything, lights dim (as normal) but the car will not crank at all. The first time this happened, I cleaned the positive and negative terminals with a tool and then the car started. But as soon as I turned it off, the boom will start to turn over. In addition, when switching the car on (or switching to any gears), the car will jolt forward hard. This made me think of the park/neutral sensor located on the transmission. I ordered the part and had it installed this morning but the car still does it.

This morning was the first time I had a portable battery on since it was a dead after 1-2 weeks of non-starting. It starts after 2 attempts but the whole jolting thing is horrible.

I'm going to send my car to a buddy's place to diagnose it more with the proper equipment. Can someone give me suggestions on what to tell him to look at specifically and check? What could this be? Starter? Battery? ETC.

Every time I clear the code, it comes back when the car starts.

BlOody_BoOger 03-23-2020 01:07 PM
Quote:
Originally Posted by Relogical (Post 3311921)
Car:

- 2013 Scion FRS (Automatic)



Battery:

- Replaced less than a year ago



Codes:

- P0700

- P0851



Replacements attempted:

- Switched out Park/Neutral Sensor



My vehicle is having trouble starting. When turning the vehicle, it will not do anything, lights dim (as normal) but the car will not crank at all. The first time this happened, I cleaned the positive and negative terminals with a tool and then the car started. But as soon as I turned it off, the boom will start to turn over. In addition, when switching the car on (or switching to any gears), the car will jolt forward hard. This made me think of the park/neutral sensor located on the transmission. I ordered the part and had it installed this morning but the car still does it.



This morning was the first time I had a portable battery on since it was a dead after 1-2 weeks of non-starting. It starts after 2 attempts but the whole jolting thing is horrible.



I'm going to send my car to a buddy's place to diagnose it more with the proper equipment. Can someone give me suggestions on what to tell him to look at specifically and check? What could this be? Starter? Battery? ETC.



Every time I clear the code, it comes back when the car starts.
Maybe it's your clutch nuetral sensor

Sent from my GM1915 using Tapatalk

BlOody_BoOger 03-23-2020 01:10 PM
Quote:
Originally Posted by Relogical (Post 3311921)
Car:

- 2013 Scion FRS (Automatic)



Battery:

- Replaced less than a year ago



Codes:

- P0700

- P0851



Replacements attempted:

- Switched out Park/Neutral Sensor



My vehicle is having trouble starting. When turning the vehicle, it will not do anything, lights dim (as normal) but the car will not crank at all. The first time this happened, I cleaned the positive and negative terminals with a tool and then the car started. But as soon as I turned it off, the boom will start to turn over. In addition, when switching the car on (or switching to any gears), the car will jolt forward hard. This made me think of the park/neutral sensor located on the transmission. I ordered the part and had it installed this morning but the car still does it.



This morning was the first time I had a portable battery on since it was a dead after 1-2 weeks of non-starting. It starts after 2 attempts but the whole jolting thing is horrible.



I'm going to send my car to a buddy's place to diagnose it more with the proper equipment. Can someone give me suggestions on what to tell him to look at specifically and check? What could this be? Starter? Battery? ETC.



Every time I clear the code, it comes back when the car starts.
It's a small pin sensor that sits way up in front of the clutch assembly. When u press down on the clutch the top part of the assembly moves forward towards the driver. And it hits this small little pin. this let's the car know that the clutch us being pressed allowing it to crank. I had this problem with my car. And was able to start the car by simply pressing on the little pin button and not even pressing the clutch in

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Relogical 03-23-2020 01:12 PM
Thank you for the reply, but unfortunately, this vehicle is an automatic.

But that did give me some more info on the set up of starting.

BlOody_BoOger 03-23-2020 01:14 PM
Quote:
Originally Posted by Relogical (Post 3311921)
Car:

- 2013 Scion FRS (Automatic)



Battery:

- Replaced less than a year ago



Codes:

- P0700

- P0851



Replacements attempted:

- Switched out Park/Neutral Sensor



My vehicle is having trouble starting. When turning the vehicle, it will not do anything, lights dim (as normal) but the car will not crank at all. The first time this happened, I cleaned the positive and negative terminals with a tool and then the car started. But as soon as I turned it off, the boom will start to turn over. In addition, when switching the car on (or switching to any gears), the car will jolt forward hard. This made me think of the park/neutral sensor located on the transmission. I ordered the part and had it installed this morning but the car still does it.



This morning was the first time I had a portable battery on since it was a dead after 1-2 weeks of non-starting. It starts after 2 attempts but the whole jolting thing is horrible.



I'm going to send my car to a buddy's place to diagnose it more with the proper equipment. Can someone give me suggestions on what to tell him to look at specifically and check? What could this be? Starter? Battery? ETC.



Every time I clear the code, it comes back when the car starts.
Here is an image. You're going to have to lay on your back. Put your car in nuetral with ebrake on. Hold down the button and turn it on. It's small and white looks like a tic tac See if that works.https://uploads.tapatalk-cdn.com/202...54d9371ceb.jpg

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BlOody_BoOger 03-23-2020 01:18 PM
Quote:
Originally Posted by Relogical (Post 3311928)
Thank you for the reply, but unfortunately, this vehicle is an automatic.

But that did give me some more info on the set up of starting.
Since it's an automatic it could be in the same location behind the brake pedal

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Relogical 03-23-2020 01:22 PM
I'll attach this to my buddy when I sent the car off tomorrow as well to look at.

BlOody_BoOger 03-23-2020 01:45 PM
Quote:
Originally Posted by Relogical (Post 3311931)
I'll attach this to my buddy when I sent the car off tomorrow as well to look at.
Lol my fix was to add folded up paper and tape it to the part where it's supposed to make contact and hit the pin[emoji2957] I kinda want to take it off. Since I know where the pin is at now, after so many times. I can reach it from sitting in the driver's seat so it's like a free kill switch [emoji23]

Sent from my GM1915 using Tapatalk

humfrz 03-23-2020 02:22 PM
Quote:
Originally Posted by BlOody_BoOger (Post 3311948)
Lol my fix was to add folded up paper and tape it to the part where it's supposed to make contact and hit the pin[emoji2957] I kinda want to take it off. Since I know where the pin is at now, after so many times. I can reach it from sitting in the driver's seat so it's like a free kill switch [emoji23]

Sent from my GM1915 using Tapatalk
:slap: his car is an auto - have another cup of coffee - :D


humfrz

BlOody_BoOger 03-23-2020 02:50 PM
Quote:
Originally Posted by humfrz (Post 3311958)
:slap: his car is an auto - have another cup of coffee - :D





humfrz
That's true but that picture only shows two pedals. So u really think it's gonna be that switch. When u sit in your car and turn the key with out hitting the brake the car doesn't crank it just turns on electronics. But when u press the brake then it cranks. So my guess is that switch is behind the brake pedal as it is behind the clutch in a manual. Honestly save the tow, and check then you'll save your buddy some time trying to figure it out.

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humfrz 03-23-2020 03:21 PM
Quote:
Originally Posted by BlOody_BoOger (Post 3311969)
That's true but that picture only shows two pedals. So u really think it's gonna be that switch. When u sit in your car and turn the key with out hitting the brake the car doesn't crank it just turns on electronics. But when u press the brake then it cranks. So my guess is that switch is behind the brake pedal as it is behind the clutch in a manual. Honestly save the tow, and check then you'll save your buddy some time trying to figure it out.

Sent from my GM1915 using Tapatalk
Oh, OK.

:)


humfrz

steve99 03-23-2020 08:47 PM
If the starter motor cranks engine its not the park\neutral switch. If its faulty it wont crank.


If car is cranking and engine fires up then its not a start circuit problem its something else.

BlOody_BoOger 03-23-2020 08:56 PM
I think it's just loose somehow idk, cuz I turn on my car by simply pressing that button without having to have the clutch engaged

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RZNT4R 03-23-2020 10:17 PM
Guys, really, holy shit, stop saying nonsense.

P0700 is a generic transmission fault code, think of it as being the transmission's way of turning on the check engine light.

P0851 is a PNP CIRCUIT LOW fault.

The transmission jerks hard in when put in gear because it's in fail-safe mode, as it feels it's TRS/PNP switch is unreliable.

The car doesn't have a clutch switch! JFC!

OP, unfortunately, throwing parts at something is a shitty way to do things. Go here, navigate to your year's repair manual, then Engine/Hybrid System -> FA20 Engine Control -> SFI System -> P0851 Park / Neutral Switch Input Circuit Low.

Step by step on how to find what's wrong, but the gist of it is, check for battery voltage across terminal 4 and 5 of the pnp connector with key on. Test light go bling = the problem is the pnp switch, or thereabouts. KEEP IN MIND! you threw a switch at it, is it correctly aligned? What caused the original no-crank condition? ASK YOURSELF! has the shift lever ever been hard to move at all? it is frequent for cars of a certain age to have shifter cables and linkages that start to bind. A linkage may bind at both ends of it's travel range, at one end of that range is the Park contact inside the switch, giving the shift lever a good slap is usually a good test of this, or just moving the lever to neutral to see if it starts there! It's called a park/neutral switch because the car can be started in either park or neutral!

steve99 03-24-2020 05:07 AM
Quote:
Originally Posted by RZNT4R (Post 3312117)
Guys, really, holy shit, stop saying nonsense.

P0700 is a generic transmission fault code, think of it as being the transmission's way of turning on the check engine light.

P0851 is a PNP CIRCUIT LOW fault.

The transmission jerks hard in when put in gear because it's in fail-safe mode, as it feels it's TRS/PNP switch is unreliable.

The car doesn't have a clutch switch! JFC!

OP, unfortunately, throwing parts at something is a shitty way to do things. Go here, navigate to your year's repair manual, then Engine/Hybrid System -> FA20 Engine Control -> SFI System -> P0851 Park / Neutral Switch Input Circuit Low.

Step by step on how to find what's wrong, but the gist of it is, check for battery voltage across terminal 4 and 5 of the pnp connector with key on. Test light go bling = the problem is the pnp switch, or thereabouts. KEEP IN MIND! you threw a switch at it, is it correctly aligned? What caused the original no-crank condition? ASK YOURSELF! has the shift lever ever been hard to move at all? it is frequent for cars of a certain age to have shifter cables and linkages that start to bind. A linkage may bind at both ends of it's travel range, at one end of that range is the Park contact inside the switch, giving the shift lever a good slap is usually a good test of this, or just moving the lever to neutral to see if it starts there! It's called a park/neutral switch because the car can be started in either park or neutral!

Would a simpler test be


If car starts\cranks in park and neutral only but not other gears then the park neutral safety switch is likely



If it starts in all gears its faulty


If it doesnt start\crank in any gear its possibly faulty.


How does the ecu work out thte PN switch is faulty ?? Does is look for vehicle moving and still getting park neutral indication ?

RZNT4R 03-24-2020 06:27 AM
No, no no. Absolutely not. You've understood this backwards, upside down and on fire, and did so on every. single. point.

Cranking in park and neutral but not other gears is NORMAL OPERATION.

If it starts in all gears you likely have a short to ground on the ECM's switch sensing circuit, and that'll trigger other fault codes (like a circuit low fault) and a fail-safe operation.

If it doesn't start in any gear it could be any piece of wire or component in any circuit related to starting the car.

The ECU never said the switch was faulty! it said "There's a transmission problem!" (P0700)
and "I see ground on my switch sensing circuit when there shouldn't be! (P0851). The detection logic is explained at the top of the diagnostic chart.

The only sure fire quick test that rules out everything but the switch or linkage is cranking in neutral but not in park.

Relogical 03-24-2020 09:21 AM
Oops, didn't get a notification for the responses.

- The car does not start unless it's in park I believe, but I can always test out the other gears.

Thank you for the additional information!!

Relogical 04-03-2020 03:22 PM
Problem solved: Documenting the end results incase someone comes in the future with this.

- The parking/Neutral switch had to be replaced. The old one was fried. I bought a used one of a part out. New one is $200.

- My running lights in the tails were not working.

- The problem was fixed after noticing a harness that leads to the rear had tears in the wire. After soldering them back on, the gear selector light turned on and the running lights turned back on.

- In addition, you need two people to align the switch correctly. One holding on to the shifter and other aligning the switch.


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