How to read OBD-I codes?? 1994 Olds 3.8L

1994 Olds Delta 88 with 3.8L engine. 80,000 miles. Check Engine Soon light goes on and off intermittently... Normally CES comes on while engine's warm and idling at stop light. (I thought the CES light would stay on once lit). Is there any way to simply jumper the contacts on the OBD-I plug under the steering column to have the code(s) flashed to the CES light. I would prefer not to spend hundreds on a code reader for a car this old. If this is doable, where is a list of OBD-I codes and their definition/explanation?

Any help would be appreciated.

Reply to
Chuck
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you can buy a code key and book for early modle gm cars at any autoparts store or at sears or a simmular tool supply place for probably under $30. the code key my step dad bought for his 88 1500 looked similuar to a code reader. count the ces flashes to get the code. you can do this with a gem clip or piece of wire and jumping a to h (dont ask me to describe the locations as i dont remember) but if you dont have a service manual with code listings this method wont be much help.

definition/explanation?

Reply to
Christopher Thompson

Look under the dash around the steering column. Find the 12 pin DLC connector. Using a paper clip, small piece of wire or a commercially available "code reader", ground terminal "A" to "B". There should only be five (5) terminals in this connector, four along the top and one on the bottom. Above the one on the bottom (M), is terminal A and B.

After grounding A to B, turn ignition key ON, do not start engine. The MIL (malfunction indicator lamp) will start to flash. One flash, short pause, two flashes, long pause, subsequent flashes. This is code 12 indicating the computer diagnostics is working. It will repeat two more times for a total of three code 12 flashes, then any stored trouble codes will display, repeating each 3 times. Code 12 will flash again when all codes have been displayed.

Your best bet is to clear the codes stored by disconnecting the negative battery cable for a minute (or remove the PCM fuse), then drive the car until the MIL comes on again, THEN check the codes. Just in case there is some old unrelated codes stored that have not been cleared.

Once you get the codes, post them here and someone with diagnostic flow charts can help you diagnose and fix the problem.

Steve

definition/explanation?

Reply to
Steve Mackie

HOLD ON HOLD ON, this information may not work for you. You you have the

12-pin connector or the 16-pin connector? To me it lookes like you have the ALDL8192 communications in this vehicle. Off-the-shelf readers will not extract the DTCs. You have to either make one, go to a mechanic that has one, or buy a really expensive one.

Steve

Reply to
Steve Mackie

Here's a crude list of DTCs though:

58 ACTMLF01 ACTIVE MALFUNCTION FLAG WORD 1 0 ACTIVE CODE 123 THROTTLE POSITION HIGH 1 ACTIVE CODE 629 INVALID PASS KEY FREQUENCY 2 ACTIVE CODE 341 INTERMITTENT CAM SIGNAL 3 ACTIVE CODE 321 18X INTERRUPTS LOST 4 ACTIVE CODE 630 BATTERY VOLTAGE OUT OF RANGE 5 ACTIVE CODE 117 COOLANT SENSOR LOW 6 ACTIVE CODE 118 COOLANT SENSOR HIGH 7 ACTIVE CODE 134 ENGINE 02 SENSOR NOT ACTIVE 59 ACTMLF02 ACTIVE MALFUNCTION FLAG WORD 2 0 ACTIVE CODE 140 CATALYST 02 SENSOR NOT ACTIVE 1 ACTIVE CODE 137 CATALYST 02 SENSOR LOW 2 ACTIVE CODE 138 CATALYST 02 SENSOR HIGH 3 ACTIVE CODE 571 TRACTION CONTROL PWM INPUT OUT OF RANGE 4 ACTIVE CODE 113 AIR TEMP SENSOR HIGH 5 ACTIVE CODE 502 VEHICLE SPEED SENSOR LOW 6 ACTIVE CODE 112 AIR TEMP SENSOR LOW 7 ACTIVE CODE 122 THROTTLE POSITION LOW 60 ACTMLF03 ACTIVE MALFUNCTION FLAG WORD 3 0 ACTIVE CODE 703 BRAKE SWITCH FAILURE 1 ACTIVE CODE 501 VEHICLE SPEED SENSOR FAILURE 2 ACTIVE CODE 755 F31 TRANSMISSION SOLENOID B FAILURE 3 ACTIVE CODE 361 EST LINE NOT TOGGLING 4 ACTIVE CODE 101 MASS AIR FLOW SENSOR FAILURE 5 ACTIVE CODE 619 OIL CHANGED INPUT FAULT 6 ACTIVE CODE 705 PRNDL SWITCH FAILURE 7 ACTIVE CODE 680 QDM5 FAILURE 61 ACTMLF04 ACTIVE MALFUNCTION FLAG WORD 4 0 ACTIVE CODE 640 QDM1 FAILURE 1 ACTIVE CODE 650 QDM2 FAILURE 2 ACTIVE CODE 132 ENGINE 02 SENSOR HIGH 3 ACTIVE CODE 131 ENGINE 02 SENSOR LOW 4 ACTIVE CODE 325 ESC FAILURE 5 ACTIVE CODE 350 EST FAILURE 6 ACTIVE CODE 342 CAM SENSOR FAILURE 7 ACTIVE CODE 740 TCC FAILURE 62 ACTMLF05 ACTIVE MALFUNCTION FLAG WORD 5 0 ACTIVE CODE 550 STEPPER MOTOR CRUZ PROBLEM 1 ACTIVE CODE 712 TRANSMISSION TEMP. SENSOR LOW 2 ACTIVE CODE 713 TRANSMISSION TEMP. SENSOR HIGH 3 ACTIVE CODE 625 HARDWARE RESET 4 ACTIVE CODE 660 QDM3 FAILURE 5 ACTIVE CODE 623 PROM ERROR 6 ACTIVE CODE 599 IN CRUZ POWER MANAGEMENT 7 ACTIVE CODE 670 QDM4 FAILURE

63 ACTMLF06 ACTIVE MALFUNCTION FLAG WORD 6 0 ACTIVE CODE 401 OBD1 DELTA RPM LINEAR EGR FLOW FAILURE 1 ACTIVE CODE 406 LINEAR EGR PINTLE POSITION ERROR 2 ACTIVE CODE 558 CRUISE VACUUM DEPLETION 3 ACTIVE CODE 562 VAC MALFUNCTION 4 ACTIVE CODE 561 VENT MALFUNCTION 5 ACTIVE CODE 531 A/C LOW FREON 6 ACTIVE CODE 626 VATS FAILURE 7 ACTIVE CODE 257 BOOST CONTROL FAILURE (OVERBOOST) 64 ACTMLF07 ACTIVE MALFUNCTION FLAG WORD 7 0 ACTIVE CODE 274 INJECTORS WIRED INCORRECTLY 1 ACTIVE CODE 573 LOSS OF SERIAL DATA ABS MSG 91 2 ACTIVE CODE 530 A/C PRESSURE SWITCH FAILURE 3 ACTIVE CODE 565 CRUZ SERVO POSITION SENSOR FAILURE 4 ACTIVE CODE 568 CRUZ SYSTEM MALFUNCTION 5 ACTIVE CODE 567 CRUZ SWITCH MALFUNCTION 6 ACTIVE CODE NOT USED 7 ACTIVE CODE 624 SOFTWARE RESET 65 ACTMLF08 ACTIVE MALFUNCTION FLAG WORD 8 0 ACTIVE CODE 125 CLOSED LOOP MIN. COOLANT TEMP. NOT MET IN TIME 1 ACTIVE CODE 171 FUEL TRIM LEAN 2 ACTIVE CODE 172 FUEL TRIM RICH 3 ACTIVE CODE 300 MISFIRE DETECTED 4 ACTIVE CODE 400 OBD2 DELTA RPM LINEAR EGR FLOW FAILURE 5 ACTIVE CODE 503 OBD2 DELTA MAP LINEAR EGR FLOW FAILURE 6 ACTIVE CODE 420 CATALYST MONITOR MALFUNCTION 7 ACTIVE CODE 484 LINEAR EGR FEEDPIPE FAILURE

Reply to
Steve Mackie

Steve, How do you make a reader for a 16 pin (OBD2) on a OBD1 system... my 95 F-bird had this bastardized setup from the factory.

Thank in adv. Stan

Reply to
BAD 4 GOOD

You may have obd 1.5. I have heard that it can not be jumped, but I just found this so now I don't know:

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Reply to
« Paul »

You need this info to make the interface:

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is a cheap two transistor version, and a slightly more expensiveMAX232 IC version, still less than $30 or so. Your connector is listed asthe 16 pin OBDII style Australian Connector. Google "F body ALDL8192" andlots of information pages should come up. Also check out
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You need CarBytes:
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You need the Data Stream info file for your vehicle, read the Index.doc file to find your stream *.DS file: ftp://ftp.diy-efi.org/pub/gmecm/ALDLstuff.zip

Steve

Reply to
Steve Mackie

OBD I is pretty useless. About the only time the light comes on is during a major problem(timing just jumped a few teeth or zero coolant or something), or smog/egr/maf related problems.

Stalling at a light is almost always the EGR or MAF on a car of this age. Basically, the EGR behaves like the car is still warming up(like an old OLD car with the choke on all the time) - and bogs down while sitting at a light.

Reply to
Joseph Oberlander

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