Checking Codes - '94 model

I have a '94 LeSabre that is my daughters daily driver. Last night the SES light came on, but it did not reappear this morning. I drove up to Autozone to see if they could read the code, but they did not have a reader that fit the connector. I have an OBDII program/cable for my laptop, but that only works on '96 and up. Can anyone tell me how to read codes on this year Buick?

The car has 101,000 miles and no sign of the 02 sensor being replaced. I bought the car from the original owner and have all receipts since new, very fortunate. Since the light appears intermittent, I gambled and put in a new sensor. The old one was almost soldered in and pretty tough to remove. The gas mileage was only in the mid-teens, which is also probably a sign the 02 sensor was heading south. I'll see if the light returns and/or mileage improves.

I'm sure other codes will appear so if anyone has method to read them, I'd appreciate it. I'm hoping the car will get the daughter through high school and maybe college. It's in perfect condition, had it painted earlier this year. (peeling GM paint)

Thanks

The O2 sensor will come out easier if the manifold is warmed to 120+ degress F or so.

Also, you did remember to use a liquid graphite+glass / conductive anti-seize compound so you can get it out again one day right?

Code reading on a non-OBDII 1994 Buick. The OBDII uses a 16-pin DLC (data link connector). I'm guessing you have a 12-pin DLC, also known as a ALDL.

1) We already know the SES bulb is working, so we can skip the turning the key to on to make sure it flashes.

2) Diagnostic codes are read by grounding the Test Terminal (pin B) to a body ground or to the Internal ECM Ground (pin A).

Pin Locations: Top row of pins. A is the right most, B is one to the left. The top row is the row closest to the little plastic "key" that prevents you from plugging the diagnostic test tool (GMs Test1) connector in upside down. The plug / pin arrangement looks something like this:
____
____________|==|____________
| F | E | X | X | B | A |
____________________________
| X | X | X | X | X | M |
____________________________

A = Ground
B = Diagnostic/Test Terminal
E = Serial Data (if used)
F = TCC (if used)
M = Serial Data
X = Unused Pins

3) With the key in the OFF position, ground terminal B to terminal A or an equivelent ground.

4) Turn the key to the ON position. The Service Engine Soon / Check Engine light should now flash. The code(s) strored in memory may be read through counting the flashes of the dashboard warning lamp.

5) NOTE: The dash warning lamp should being to flash Code 12. The code with display as one flash, a pause, and then two flashes. Code 12 is not a fault code, it is used as a system acknowledgement or "handshake" code which indicates that the ECM is working. Code 12 is used to begin EVERY diagnostic sequence. Some vehicles will also use Code 12 after all diagnostic codes have been sent to indicate the end of error code read out.

6) After Code 12 has been transmitted (3) times, the fault codes (if any) will each be transmitted (3) times. Note: The codes are stored and transmitted in numeric order from lowest to highest. The order of codes does not indicate the order of occurance.

7) If no codes are stored, but driveability problems are evident, the system will need to be diagnosed by a qualified mechanic. The ECM may need to be replaced.

8) If one or more codes are stored, record them and refer to the applicable Diagnostic Code Chart for the 12-pin DLC / GM ALDL.

I have a copy of the chart here, but I'm not going to type the whole thing out. Just post the codes to the board and/or PM me, and I'll look them up. Posting to board may get you a 15 minute reply though, as I'm sure there are many people here with a copy of this chart.

http://www.automotiveforums.com/vbulletin/#
2cents Also, may I just say... MY ABOVE ASCII ART RULES. Everyone best be impressed... I just put like.. 45 minutes into this message. I think I'll go take a shower now. I was hoping to get to AutoZone to borrow their OBD-II reader myself.

-MC

OK... well my ASCII are WOULD have rulled if the system would not have removed duplicate spaces and used the fixed width font I typed it in. That's what I get for not previewing replies.

We'll try some HTML FONT tags for Courier New and see what happens. Here is the pin out diagram again.


__________|==|___________
| F | E | X | X | B | A |
_________________________
| X | X | X | X | X | M |
_________________________

A = Ground
B = Diagnostic/Test Terminal
E = Serial Data (if used)
F = TCC (if used)
M = Serial Data
X = Unused Pins

Wow, thanks for the efforts. Since my OBDII 16 pin connector won't work, I assume it's a 12 pin. I pulled the sensor while the car was still warm, a little PB Blaster did the trick. Used a Bosch sensor, good bit of anti-seize on the threads, with a plastic protector. Guess enough folks didn't remember to coat prior to installation.

Daughter has the car, I'll read the code tomorrow. I used to be able to read flashes on my '93 Nissan NX2000 in a similar manner, I thought there may be a way to do the same on the Buick. Autozone used to give you a key to ground the two pins, no longer available. I had one, but probably tossed it long ago.

If you lived near me, I'd happily let you use my OBDII scan-tool on the laptop. I use Alex Peper's OBD-2 program, it's relatively inexpensive but you need a laptop. It's worked pretty well and has a specific program for my '96 Chevy Impala SS. It must be the 96 model, yeare, which has had more than it's share of CEL's so the program has more than paid for itself. I also had a '96 Firebird Formula with the same LT1 powertrain, but that was less troublesome. I haven't tried it on our new truck but it's read codes on my Honda and parents Subaru.

Thanks again, I'll post what codes I read.
Al

Thanks for the offer, up until about 6 hours ago, that's what I thought I needed. Unfortunately, I found out today that my OBD connector really isn't an OBD connector.

See my upcoming new thread. (I wrote so much here that got so far off topic, I decieded I didn't want to subject you to that.)