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Electrical Eec Pin To Ground Measurements, E.g., Resistance, Voltage

  • Thread starter Thread starter DuderMcMerican
  • Start date Start date Mar 8, 2016
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    eec electrical ground measurements pins
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DuderMcMerican

Active Member
Mar 7, 2016
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Woodbridge, VA
Mar 8, 2016
#1
  • Mar 8, 2016
  • #1
Hey gang,

Is there a list/reference that gives normal specs for when checking eec pins with multimeter?

I tested all eec pins' resistance with known ground (battery disconnected) and got what i suspect are some abnormal readings for several of them (all eec grounds seem fine though).

Relatedly, is there a flow chart or something that indicates probable causes when more than one pin tests out of spec, e.g., if pin X and pin Y are out of spec, then check Z?

Thanks!
 

jrichker

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#2
  • Mar 8, 2016
  • #2
What are you trying to do?

The most useful thing you can do to check the computer is to dump the codes.Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. I highly suggest that you read it and follow the instructions to dump the codes.

Resistance checks on the actual computer pins will not provide useful information. The sole exception to this is the resistance between pin 46, signal ground and pins 40 and 60 computer power ground. That should be less than one ohm.
 
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DuderMcMerican

Active Member
Mar 7, 2016
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Woodbridge, VA
Mar 8, 2016
#3
  • Mar 8, 2016
  • #3
Thanks, jrichker. I'm obvi a complete newb. Haha. I appreciate your patience.

I have pulled codes and dumped them before (thanks to your tutorials), but now I'm not even able to pull codes. Fuel pump comes on but test won't initiate (paperclip jumper method).

Also, theres recently been a lot of clicking coming from eec/eec relay area with KOEO and even KOER for a short while (on the rare occassion the car starts/runs w/o stalling after 10 sec). I'm experiencing a "crank no start/surging idle/start stall" combo. I've worked a little bit of the step by step tutorials on these issues, but the symptoms are never consistent so it's easy to get sidetracked chasing symptoms. And now that i can't pull codes i got sidetracked once again bc i figured that I'd need to remedy that eec thing first.

Unfortunately, i lost the paper where i wrote down my codes from when i could pull them, but one was def 41 and i was also getting an "out of range" code too at some point (maybe 12 or 13). I think these were KOER codes but it's been a while so not 100% sure.. I feel like an idiot for losing that record.

Anyway, i was thinking it might be an electrical issue bc the problems are intermittent. Sometimes the car runs pretty decent..

I have replaced vacuum lines and vacuum pressure is within range. I also replaced the egr bc i accidentally broke the old one trying to remove it for testing. I also replaced iac bc it was missing the gasket. I replaced plugs, wires, dizzy cap/rotor bc they were due, and ignition coil bc old one was weak. I've also cleaned maf sensor, adjusted tps, and cleaned throttle body. I also switched out maf with a buddies but it did nothing. I have also checked continuity of o2 sensors harness to eec and passenger side has continuity but drivers side does not (so far ive backprobed up past the connector that sits behind the air box). I think that covers most of it so far.. My main issue is dealing with the inconsistent intermittent symptoms, which gets me sidetracked. Electrical?

What do you think?

Btw it's a stock 1990 LX 5.0.
 
D

DuderMcMerican

Active Member
Mar 7, 2016
148
9
28
Woodbridge, VA
Mar 8, 2016
#4
  • Mar 8, 2016
  • #4
When i said "theres recently been a lot of clicking coming from eec/eec relay area with KOEO and even KOER for a short while" i meant always--not just when tryin to pull/dump codes
 
D

DuderMcMerican

Active Member
Mar 7, 2016
148
9
28
Woodbridge, VA
Mar 8, 2016
#5
  • Mar 8, 2016
  • #5
Update:

Pin 46-40, infinite resistance
Pin 46-60, infinite resistance
Pin 40-60 no resistance
 
D

DuderMcMerican

Active Member
Mar 7, 2016
148
9
28
Woodbridge, VA
Mar 8, 2016
#6
  • Mar 8, 2016
  • #6
DuderMcMerican said:
Update:

Pin 46-40, infinite resistance
Pin 46-60, infinite resistance
Pin 40-60 no resistance
Click to expand...

Another update:

jrichker: I found your 29 Feb 2016 post in reply to mark32 who was having similar eec/no codes issue, so i will also try checking resistance between ports 46 and 40/60 on the computer itself. I will update thread.. Thanks!
 
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