my comp wont throw codes, HELP

[D347643]

I have tried to check my codes on my comp and it wont throw them anymore. I used the paper clip test light method with a known good test light and 12v power source and it wont flash at all. Kinda frustrating since it worked a month ago and now it wont. About a week ago I was checking my timing and my number 7 plug wire shorted against my speedo cable and was shocking me everytime i touched the body of the car. Then my car wouldnt restart after i shut her off. Could I have fried PART of my comp? My car RUNS now that i fixed the short but it idles kinda funky and i have the no codes problem also. Any ideas? is there a way to test my comp?

btw I checked the resistance on the wires from the dlc to the comp and everything was good so no breaks

thanks

Drew

 

[tmoss]

You did have it in neutral right? If the neutral switch is bad the computer won't give codes on 5 speeds.

 

[D347643]

yes it was in neutral. also like i said it threw codes fine about a month ago when i last checked them

Drew

 

[jrichker]

Check the resistance between the black/white wire (#46) on the self test connector and battery ground. You should see less than 1 ohm.
diagram courtsey of Tmoss & Stang&2birds

See http://www.veryuseful.com/mustang/tech/ for more good stuff...

 

[tmoss]

Try jumping the nuetral switch just to be sure it's not that..........

 

[D347643]

if my neutral safety switch isnt working then my car wouldnt start, right?

 

[tmoss]

You have the clutch interlock switch (no start) and the neutral sensing switch (to give codes) confused.

 

[D347643]

oh durrrr , thanks tmoss
so if there is more than 1 ohm between that wire and ground while the car is in neutral that means the switch is bad or there is too much resistance in the wiring....gotcha!

 

[MYLX5.0]

I am kinda having the same problem, I found that my number 6 and 8 plug wires were arcing on my headers. Now my Check Engine Light is on and I took it to a shop and they said that my computer wasnt responding to anything he did. My car idles kinda poorly, but runs better than usual above 1500 RPM.

Sorry, I don't mean to be stealing a thread, but they seemed very similar and I could really use the help.

 

[D347643]

thats cool. So i grounjded out my sig return line before my neutral safety switch and everything is kosher

 

[tmoss]

switch must be bad - or a connection loose.

 

[D347643]

yeah ill have to check on that but for the meanwhile should i just leave my ground as is? I crimped an eyelet on the end and screwed it to the body

 

[tmoss]

Yeah, but I would fix it when you get a chance.

 

[mattfleming]

I have a 5 speed car.. My clutch switch currently is bypassed (previous owner)

Could that be a reason i can't pull codes? I tested pin 46 and had near 0 resistance after some sandpaper touchup on the STO pin.

 

[HISSIN50]

I have a 5 speed car.. My clutch switch currently is bypassed (previous owner)

Could that be a reason i can't pull codes? I tested pin 46 and had near 0 resistance after some sandpaper touchup on the STO pin.

See Tmoss's post #7 above. The clutch-safety-switch has nothing to do with it (this is the switch on the clutch pedal you push to close the starter interlock circuit - to let the car start).
It sounds like this is what you are talking about and it does not affect code retrieval (as Tom already said).

Good luck.

 

[mattfleming]

I was just wondering.. I trested some wires today.. none of the sensors attached to pin 46 ground were bad.. I'm still getting the "voltage on" symptom..
Where is this Neutral Gear Switch?
Can i ground out pin 30 and bypass this feature?

 

[bcd]

how do you jump the neutral safety switch? i tore my wires when i removed my transmission and i'm pretty sure that was one of them