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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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tried pulling codes with tester light stays on

  • Thread starter Thread starter westridez
  • Start date Start date May 20, 2005

westridez

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Mar 31, 2005
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May 20, 2005
#1
  • May 20, 2005
  • #1
i bought a code reader from walmart and hooked it up when i try testing it the light just stays on i left it on for 5 minutes still nothin what could it be?
 

Black1987Stang

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Aug 22, 2004
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May 20, 2005
#2
  • May 20, 2005
  • #2
Did you turn the key on run? I have the same one, black and yellow sticker box with little red light and a beeper and a single and diferent group of prongs on top? The first time i hooked it up it was doing that and i was confused then i noticed i had the wrong single wire hookup to it. On my 87 there are the normal self diagnostic hookup and TWO single wire connectors. I had the wrong one hooked up, i think it was for the stock underhood light since now i have an aftermarket hood. One is black and the other is like a gray. Hope this helps.
 

westridez

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Mar 31, 2005
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May 20, 2005
#3
  • May 20, 2005
  • #3
87stangdiddle said:
Did you turn the key on run? I have the same one, black and yellow sticker box with little red light and a beeper and a single and diferent group of prongs on top? The first time i hooked it up it was doing that and i was confused then i noticed i had the wrong single wire hookup to it. On my 87 there are the normal self diagnostic hookup and TWO single wire connectors. I had the wrong one hooked up, i think it was for the stock underhood light since now i have an aftermarket hood. One is black and the other is like a gray. Hope this helps.
Click to expand...
is the wire im looking for come out of the same harness as the big plug just down further
 

HISSIN50

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May 21, 2005
#4
  • May 21, 2005
  • #4
I would run codes by hand to see if you can. good luck.
 

Black1987Stang

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May 21, 2005
#5
  • May 21, 2005
  • #5
Yea it comes out of the same harness, its a orangy color wire and a light grey connector. The one you dont want is a black connector and it comes out of a seperate harness so just make sure you use the one that comes out of the same harness as the big plug.
 

westridez

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Mar 31, 2005
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May 21, 2005
#6
  • May 21, 2005
  • #6
im pretty sure thats the one i used but the light just stays on never blinks what could be wrong
 
S

SPEED FREAK

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Aug 7, 2000
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May 21, 2005
#7
  • May 21, 2005
  • #7
westridez said:
im pretty sure thats the one i used but the light just stays on never blinks what could be wrong
Click to expand...

There is a large black connector which is psuedo prism shaped and a small grey square connector with a single wire they both need to be plugged in with the key off. Once they are in there, put the key to the run position and read away.
 

westridez

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Mar 31, 2005
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May 21, 2005
#8
  • May 21, 2005
  • #8
SPEED FREAK said:
There is a large black connector which is psuedo prism shaped and a small grey square connector with a single wire they both need to be plugged in with the key off. Once they are in there, put the key to the run position and read away.
Click to expand...
thats what i did and the light was still on
 

jrichker

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May 21, 2005
#9
  • May 21, 2005
  • #9
You may have some wiring problems. Use a DVM or Ohmmeter and measure the resistance between the black/white wire in the lage connector and battery ground. You should see less than .5 ohm.

Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter.
 

westridez

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Mar 31, 2005
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May 24, 2005
#10
  • May 24, 2005
  • #10
jrichker said:
You may have some wiring problems. Use a DVM or Ohmmeter and measure the resistance between the black/white wire in the lage connector and battery ground. You should see less than .5 ohm.

Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter.
Click to expand...
alright all try that thanks
 
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