Check Engine Light Help

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White/pink and red/lt blue basically will connect together when the car is in park or Neutral. If you shift into drive, Reverse, etc, then the switch should open (disconnect) those two wires.

So when I test a switch like this, I disconnect the electrical connector to it. With the car in Park, your DMM set to ohms, and a lead on each of those above-listed wires, you should see a very low reading.

Then shift the car into R or D and retest it. The reading should be REALLY high/infinite resistance.
 
I think that was your power.test fa7 if less than 1 goto fa9.check ac input? Unplug 60 pin key on eng off dvom set at 20v scale ck volts pin 10 and cha grd.is volts more than 1v?if yes service short to power in ac clutch circuit.if no rerun quick test .when u tested 30 to cha.if more than 1v goto fa8 ck neutral drive switch.key off dvom set at 200ohms .unplug harness at nds and measure resistance across the switch less than 5ohms?if yes service short in vehicle harness nd circuit.if no replace nds
 
I have searched all the forums and maybe I just did not use the right keywords or phrase but I could not find an anwser to my question. And sorry if this is not posted to the right spot. Also sorry for the length just trying to provide enough information.

I have another good technical question for the 5.0 Mustang Forum. First a little background on the situation, I picked up a four cylinder 89 Notch for 600.00 minus the motor and trans and performed a V8 swap (AER manufacturing 306 long block, FRPP E-303 cam, FRPP 1.6 rockers, FRPP 24 lb injectors, 70 mm TB, FRPP Tubular intake, BBK shorty headers, H-pipe, MSD billet distributor, MSD A6L, MSD coil) replaced the computer with an A9L, complete engine wiring harness, fuel injector harness, headlight wiring harness with a 3G alternator upgrade, all were from an 89. None of the harnesses have any splices or repairs made to them other than where I adapted the alternator upgrade, all sensors, switches were installed new.

And now the Question, I get a check engine light coming on after driving it 10-20 minutes, if you shut the car off and start it right back up it does not come back on until after 10-20 minutes again and the local auto shop is unable to pull any codes because they cannot communicate with the computer. I switched the computer out from 89 notch with my 89 convertible and they can read it there fine. The car runs fine until the check engine light comes on then it runs sluggish. I drove the car for about 300-400 miles before check engine light problem started.

Any help on this is greatly appreciated.

Is it possible that you need to have your oxygen sensors changed?:)
 
Ok checked 03 manual and those 4 circuits are still used to day.your test pin30 to cha grd failed. what i did find you should know already but anyway .orange is .12v fused main in.black/pk feed to back up lite.red/lb hot in start. Than the other wh/pk is switch p-n start circuit.
 
Mercedez, the problem so far was the ground wire for the HEGO was broken inside the insulation and once that was repaired and I regrounded it to the firewall it cleared up the code issues except for the code 67 which hotcobra03 and HISSIN50 have been providing great information on how to troubleshoot and try to fix.
 
I think that was your power.test fa7 if less than 1 goto fa9.check ac input? Unplug 60 pin key on eng off dvom set at 20v scale ck volts pin 10 and cha grd.is volts more than 1v?if yes service short to power in ac clutch circuit.if no rerun quick test .when u tested 30 to cha.if more than 1v goto fa8 ck neutral drive switch.key off dvom set at 200ohms .unplug harness at nds and measure resistance across the switch less than 5ohms?if yes service short in vehicle harness nd circuit.if no replace nds

I do not have any ac input to check there is not ac equipment or switches installed except for the knob on the dash.

I have not tested the resistance at the nds switch yet but will post when I do.

I will also check pin 10 to cha ground but it will probably will not read correctly since the ac pressure switch and compressor harness are not plugged into anything. (which I am beginning to think might actually be the reason for the code 67)

Does it not make sense that because I get a code 85 - Canister Purge Solenoid circuit failure because the solenoid is not plugged in,

That since no ac pressure switch is plugged in I could/would possibly get the code -67?

Thanks for the time and help.
 
Ok rock im learning with you.hissin is awsome and i learned more in this post than last 5yrs. When key is on orange should be 12v and pin 30 should be 12v. You switch sounds bad .if you jump orange and wh/pk than rerun koeo test ?
 
Mercedez, the problem so far was the ground wire for the HEGO was broken inside the insulation and once that was repaired and I regrounded it to the firewall it cleared up the code issues except for the code 67 which hotcobra03 and HISSIN50 have been providing great information on how to troubleshoot and try to fix.

What about the ground wire?
 
This is a thought on cruise. The 2.3 harness shows a 2nd jumper. At the servo motor other than mt/auto jumper stay on 67 nss nss also should lite reverse lites in r engine off if orange is hot the other 2 appear ok cause car starts but the are feed from starting system.also maybe a relay for ac harness might be enough to clear 67 it never said it has to be working .just a complete circuit. Cant wait till evap code tricks .my own nightmare is po455 .
 
hotcobra03, I will not be able to check anything until Sunday at the earliest but I will post what I find. I am beginning to think that maybe since I have the ac pressure switch disconnected it could messing with code 67, yes the reverse lights work fine and the car only starts in park or neutral.

Mercedez, the orange (HEGO) ground wire at the back of the engine, on the injector harness was broken inside the insulation, once I repaired it and regrounded it all the other codes went away.


Thanks for the help.
 
When key is on orange is 12v and pin 30 is 12v. if you jump orange and wh/pk still shows code 67. I am about :fuss: :bang: feed up with this one code. I am going to wait until I can get a ac pressure switch to plug in because the nss only allows the the car to start in neutral or park and the reverse lights work. If the code 67 is still there after the ac pressure switch I will try the ac relay then replace the nss and let you know what happens.

I hate electrical gremlins :mad:

And next is the cruise control not working, but the horns work.

Thanks for all the help and ideas.
 
Thanks hotcobra03 and HISSIN50 for the time and help, sorry I have not added any new responses. I got the AC pressure switch from all my AC stuff I took out and hooked it up and cleared the computer and it still shows code 67. So it is either the NDS switch on the trans or the computer harness I got came out of a standard. I did a mass air conversion on an 87 and never worried about wether the harness was a standard or auto and never had any codes because I was told the harness did not matter as long as the correct year was used, ie 1988-1990.

Anyways thanks for all the help and time you two spent trying to help and hope you both have great holidays and I will update this when I get working it after the holidays.
 
code 67?

How do I test the Neutral safety circuit failure code 67, to see if the switch is bad, because it looks like that could be the cause of the problem? Pin 46 which appears to be the wire causing the problems ends at the Neutral switch. I can not find any breaks in 46 going anywhere.

Thanks

hey read thru your new codes and all but 85 ties to signal return pin 46,,,this is what my book has... pin test FA7-check neutral drive input,,...key off,wait 10 sec,...verify heater control is in off position,if so equipped.....verify trans is in neutral or park,,,,,koeo dvom set to 20 volt scale.....measure voltage between pin 30 at 60 pin connector and chassis grd,,,is voltage less than 1.0 volts???yes go to FA9 no go to FA8.... pin test FA8,,,check neautral drive switch,,,key off wait 10 sec,,dvom set on 200 ohm scale,,,locate the neutral drive switch..disconnect harness from switch and measure resistance across the switch,,is resistance less than 5 ohms??????switch in pic has 4 posts..looks like both ends you check but im not sure hission50 does,,,,,if yes service open in harness if no replace nds,,,from that is goes to ac circuit for code 67.. i recall back some post it looked like you might be able to bypass this,,,i am going to give you some wire diagrams that are close enough to follom your 4 circuits and the pin test for 03...read it and you will see your stuff in thier some test are different but they are still used.
 
very long post

Thanks hotcobra03 and HISSIN50 for the time and help, sorry I have not added any new responses. I got the AC pressure switch from all my AC stuff I took out and hooked it up and cleared the computer and it still shows code 67. So it is either the NDS switch on the trans or the computer harness I got came out of a standard. I did a mass air conversion on an 87 and never worried about wether the harness was a standard or auto and never had any codes because I was told the harness did not matter as long as the correct year was used, ie 1988-1990.

Anyways thanks for all the help and time you two spent trying to help and hope you both have great holidays and I will update this when I get working it after the holidays.
hey you have a safe holiday too ....took all afternoon too read up on this,something here has been overlooked or missed between me getting in the way,,,at first i was stuck on harness also but after learning the circuits it should work,but like the ac and cruise and manual harness combined together could be where problem lyes.. the test on jumping orange to pin 30 will tell what code 67 is,, cant remember what results were or if it was done yet,,, just the test at pin 30 before using jumper.iirc you failed it and jumping orange for power to pin 30 and see if code 67 goes away,,hope so ,if not maybe start back at begining
 
Some refresher information on code 67...

Code 67 - clutch not depressed (5 speed) or car not in neutral or park (auto) or A/C in On position when codes
where dumped. Possible neutral safety switch or wiring problem. This code may prevent you from running the Key On
Engine On tests. You can generally ignore this code, since it has no effect on engine performance.

The computer wants to make sure the A/C is off due to the added load on the engine for the engine running tests. It also
checks to see that the transmission is in Neutral or the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents
the diagnostics from being run when the car is driven. Key On Engine Running test mode takes the throttle control away
from the driver for several tests. This could prove hazardous if the computer was jumpered into test mode and then driven.

The NSS code 67 can be bypassed for testing. You will need to temporarily ground computer pin 30 to the chassis.
Computer pin 30 uses a Lt blue/yellow wire. Remove the passenger side kick panel and then remove the plastic cover from
the computer wiring connector. Use a safety pin to probe the connector from the rear. Jumper the safety pin to the
ground near the computer.

IF YOU JUMPER THE WIRING TO BYPASS THE NSS, BE SURE TO REMOVE IT PRIOR TO DRIVING THE CAR!!! YOU COULD END UP CRASHING AND BURNING!!!
 
Does anyone have a better wiring diagram for the O2 sensor harness for both the manual and auto? I was told that they are different and that the wrong O2 harness could be causing the code 67, and could cause the computer to ground out internally and I am not sure which O2 harness I have. All I have been able to find so far is a different part number for each but I dont have a part on mine.
 

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o2s

Does anyone have a better wiring diagram for the O2 sensor harness for both the manual and auto? I was told that they are different and that the wrong O2 harness could be causing the code 67, and could cause the computer to ground out internally and I am not sure which O2 harness I have. All I have been able to find so far is a different part number for each but I dont have a part on mine.

hey i dont have pic of o2s but all i can see is thier is a left and right. now after thinking code 85 ties to 02s in fuel control,but code 85 here is a continuous memory code ,,which now brings up another thought,,,checking the codes by counting the blinks,,,code 57 is also nds... i have i hand held reader and when i read what ford claims will happen while doing a koeo test it might be hard to read...fords book says you will get 2 sets of codes with the 2nd half being continuous codes..are you also resetting pcm before retesting....only thing i cant answer is pin 30..when test asked if volts were more than 1 volt if 12 volts should be what you are looking for..im assuming yes... give a new update when you can..i will hang with you till the end i must know what was the cause
 
Ok guys here is an update

I took the canP harness/switch (known good) off my 89 vert, I hooked my EGR back up, I also put the AC pressure switch back on and hooked it up. I cleared the computer. Cranked the car and let it run for about 15 minutes and when I pulled the codes I got

KOEO
67
CM
33

I am going to take the EGR valve (known good) off my 89 vert next, I want to try to eliminate all other codes so I know all circuits are working, because I can not find any broken, disconnected wires anywhere, and I just do not want to buy switches withou knowing for sure.

I am about :fuss::mad: and feedup with this thing right now. I know it will turn out to be something so simple though.

Thanks for all the great advice and help so far guys.