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need some help with codes and code scanner

  • Thread starter Thread starter GeLsTaNg215
  • Start date Start date Mar 27, 2006

GeLsTaNg215

New Member
Dec 7, 2004
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Philly, PA
Mar 27, 2006
#1
  • Mar 27, 2006
  • #1
Okay well I got this code scanner below in the pic


I hooked it up to the plug on the driver side by the firewall. First I tried to run the test with key on engine off and it wouldnt show any codes it would just stay on the three zeros in test mode. But when I did the test with key on engine running it gave me codes 21, 44 and 94. Aside from the codes it gave while the car was on, Why wont it test with the key on engine off like its suppose to??? im so stumped! anybody ever have this problem with a code scanner?
 
9

90bronconate

New Member
Apr 24, 2005
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Phoenix, AZ
Mar 27, 2006
#2
  • Mar 27, 2006
  • #2
did you plug both the big (3 prong) and the little (1 prong) plug in? for KOEO it should spit out a 111 if everything is good.
 

GeLsTaNg215

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Dec 7, 2004
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Philly, PA
Mar 27, 2006
#3
  • Mar 27, 2006
  • #3
Yea sorry for not being specific I plugged both plugs, everything had to be hooked up right though because I got codes with the engine running. And I know theres gotta be alot of codes lol cause my car is running like complete crap!!!!
 

AUBURN1111

Founding Member
Oct 17, 2000
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Mobile, AL
Mar 27, 2006
#4
  • Mar 27, 2006
  • #4
For the KOEO codes I had to sit inside my car and count the check engine light flashes to get my codes. I have a similar scanner. You should hear it testing all the relays and fuel pump etc. before it gives out any codes.
 

GeLsTaNg215

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Dec 7, 2004
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Philly, PA
Mar 27, 2006
#5
  • Mar 27, 2006
  • #5
My car doesnt have a check engine light so I cant count the beeps. The first time I tried doing the koeo test I heard the fuel pump and some clicking but it didnt display any codes. Though, the first time I might have unhooked it too fast because I didnt see anything, but then after that everytime i tried testing koeo I didnt hear the fuel pump or clicking sounds I really hope I didnt spend 30 bucks for nothing
 

sunil6784

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Mar 31, 2005
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Boston, MA
Mar 27, 2006
#6
  • Mar 27, 2006
  • #6
I dunno...I have that same scanner and I have had no problems... maybe you got a dud ? or maybe its something with your test port/computer?
 

GeLsTaNg215

New Member
Dec 7, 2004
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Philly, PA
Mar 27, 2006
#7
  • Mar 27, 2006
  • #7
Damn, I dont know. I mean it works while the car is running so that means it obviously works but the question is why it wont work when the engine is off Another thing I noticed is when I try it with the engine off it just sits there and tests and shows nothing but soon as I turn the key off a little square appears next to the numbers but no numbers and it isnt blinking like it should be. Owell i'll have to mess with it more and hope I can fix it. But aside from that problem anybody got any clues on what I should look for on code 21, 44 and 94 while engine is running??
 

jrichker

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Mar 28, 2006
#8
  • Mar 28, 2006
  • #8
Standard procedure for getting the codes has two parts:
1.) Key on, engine not running(KOEO). This retrieves the stored codes.
2.) Key on, Engine running (KOER). This retrieves the codes present at the time the engine is running. It also enables you to do things like the cylinder balance test.

Code 21 – ECT sensor out of range. Broken or damaged wiring, bad ECT sensor. Note that that if the outside air temp is below 50 degrees F that the test for the ECT can be in error.

The ECT sensor has absolutely nothing to do with the temperature gauge. They are different animals. The ECT sensor is normally located it the RH front of the engine in the water feed tubes for the heater.

The ACT & ECT have the same thermistor, so the table values are the same

ACT & ECT test data:

Use Pin 46 on the computer for ground for both ECT & ACT to get most accurate readings.

Pin 7 on the computer - ECT signal in. at 176 degrees F it should be .80 volts

Pin 25 on the computer - ACT signal in. at 50 degrees F it should be 3.5 volts. It is a good number if the ACT is mounted in the inlet airbox. If it is mounted in the lower intake manifold, the voltage readings will be lower because of the heat transfer.

Voltages may be measured across the ECT/ACT by probing the connector from the rear. Use care in doing it so that you don't damage the wiring or connector.

Here's the table :

68 degrees F = 3.02 v
86 degrees F = 2.62 v
104 degrees F = 2.16 v
122 degrees F = 1.72 v
140 degrees F = 1.35 v
158 degrees F = 1.04 v
176 degrees F = .80 v
194 degrees F = .61

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.

Ohms measures at the computer with the computer disconnected, or at the sensor with the sensor disconnected.
50 degrees F = 58.75 K ohms
68 degrees F = 37.30 K ohms
86 degrees F = 27.27 K ohms
104 degrees F = 16.15 K ohms
122 degrees F = 10.97 K ohms
140 degrees F = 7.60 K ohms
158 degrees F = 5.37 K ohms
176 degrees F = 3.84 K ohms
194 degrees F = 2.80 K ohms

Codes 94 & 44 - AIR system inoperative - Air Injection. Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.
The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.

Remember that the computer does not source power for any actuator or relay, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.

The computer provides the ground to complete the circuit to power the solenoid valve that turns the vacuum on or off. The computer is located under the passenger side kick panel. Remove the kick panel & the cover over the computer wiring connector pins. Check Pin 38 Solenoid valve #1 that provides vacuum to the first Thermactor control valve for a switch from 12-14 volts to 1 volt or less. Do the same with pin 32 solenoid valve #2 that provides vacuum to the second Thermactor control valve. Starting the engine with the computer jumpered to self test mode will cause all the actuators to toggle on and off. If after doing this and you see no switching of the voltage on and off, you can start testing the wiring for shorts to ground and broken wiring. An Ohm check to ground with the computer connector disconnected & the solenoid valves disconnected should show open circuit between the pin 32 and ground and again on pin 38 and ground. In like manner, there should be less than 1 ohm between pin 32 and solenoid valve #2 and pin 38 & Solenoid valve #1.

If after checking the resistance of the wiring & you are sure that there are no wiring faults, start looking at the solenoid valves. If you disconnect them, you can jumper power & ground to them to verify operation. Power & ground supplied should turn on the vacuum flow, remove either one and the vacuum should stop flowing.
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
 
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