[sad-lumina-owner]

Originally Posted by cbec1999

If you have a check engine light, you have code(s). And if the light goes out when you turn off at night, then it will blink your codes under the right circumstances. One of those circumstances is with a paper clip.

If your ALDL connector is different than the one I posted, you need to identify the pinouts for yours, and find out which 2, when jumped, will tell you your codes.

I know you're finding it hard to believe, but reading codes on this /94 Lumina with a /95 Monte Carlo ECM/PCM is simply bullshit.

I have done a search, to prove to myself that I am indeed not living in an alternate universe, but the same one in which you reside.

I found the following informative, but utterly useless to a Canadian post:

http://www.automotiveforums.com/vbul....php?p=5711717


...
The only 95's that come with OBD2 are the ones that were sold in California with the 3.8's. If it's got a 3.4, then it's definitely OBD1.

I never found any paper clip trick to work.

But what I did find to work was educating the people at Advanced Auto parts on how to use their diagnosis scanners. If you're trying to find out the codes in your system, then I would recommend this.

Go up to Advance Auto, Autozone, or whatever auto parts store you have around you.

Tell the person that you need to have you car scanned for codes. They'll ask what year is it for, you say 1995. They say "Sorry, it has to be 1996 and up for us to scan it." This is the fun part.. Explain to then that you have an OBD2 port in your car, so they can scan it. This should intrigue them enough to at least go out and give it a look over. Now when the person comes out to the car to scan it, tell him/her to manually enter the cars information (Year/Make/Model/Engine) into the scanner device, and then hook it up to the OBD port to scan it. It should scan fine, and they should take you back inside to print out the codes showing what was wrong.

The majority of the employees don't realize that their scanners do read OBD1 codes, they're just not taught how to fully use them. They don't have a cord that plugs into the OBD1 port, that's why they tell everyone with OBD1 that they can't scan it. But their scanners will read OBD1, that's why you must enter the cars information into the scanner. Otherwise, if the employee just hooks it up to the port and starts to try to scan, it will say there was an error. Once the employee enters the information about the car into the scanner, it then recognizes that it will be reading an OBD1 system instead, and should work just fine for you.

In case you're wondering, yes I've had this run in several times.
__________________
- Jason

P.S.:

/94 Lumina owners should note with horror and amusement, that this pinout for the ALLEGED scancodes is ALSO nothing at all like the actual wiring they will find under their dash.

Another link in the above thread gives the actual (original) pinout for the smaller plug:

Title:Pre-1996 ENGINE Trouble Codes



Author:Tink



So your "check engine" or "service engine soon" light has come on. If you have a pre-1996**, you don't need an expensive scan-tool or code reader to check the codes, just a simple paper clip. Locate the ALDL (Assembly Line Diagnostic Lead). It is usually under the driver's side of the dash. For most 1994 and back (OBD 1, 12 pin ALDL) short terminals A & B.

In 1995 GM changed to OBD 1.5. Some late 1994 models are also OBD 1.5. For these (OBD 1.5, 16 pin ALDL) short terminals 5 & 6.

Turn key on, but do not start engine. Find and Short terminals with a paper clip. The check engine light will begin to flash. The ECM (computer) will display a "code 12" by flashing the "service engine soon" light, indicating that the system is operating. A code 12 is simply one flash, followed by a brief pause, then two flashes in quick succession. This code will be flashed 3 times. If no other codes are stored, code 12 will flash until the diagnostic terminal ground is removed. After flashing code 12 3 times, the ECM will display any stored trouble codes. Each code will be flashed 3 times, then code 12 will be flashed again, indicating that the display of any stored trouble codes has been completed.

However, In my car, the pinout is actually different again, with wires going to pin 6 and 12, (not 5).

But all this is moot in any case, since I have already explained in several previous posts that I have shorted out every possible combination of live pins in the plug with NO CODES flashed as a result. This finding is identical to that of the poster quoted above.

Paper Clips don't work on this LEMON.