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GM OBD1 DTC codes for 1995 and older

Discussion in 'General Chevy & GM Tech Questions' started by unplugged, Oct 12, 2009.

  1. unplugged

    unplugged New Member 1000 Posts 100 Posts

    These are the GM specific OBD1 DTC codes:

    GM common codes for OBD1 (for vehicles made before 1995)
    12 System normal
    13 oxygen sensor circuit open
    14 coolant sensor high resistance or shorted
    15 coolant sensor circuit low or open
    16 direct ignition system (DIS) fault in circuit
    17 cam position sensor fault
    18 crank or cam sensor error
    19 crank sensor circuit fault
    21 tps sensor out of range
    22 tps sensor signal voltage low
    23 intake air temp sensor out of range, low
    24 vehicle speed (vss) sensor circuit fault
    25 air temp sensor sensor out of range, high
    26 quad-driver module (computer) circuit #1 fault
    27 quad-driver module (computer) 2nd gear circuit
    28 quad-driver module (computer) circuit #2 fault
    29 quad driver module (computer) 4th gear circuit
    31 cam position sensor fault
    32 egr circuit fault
    33 map sensor signal out of range, high
    34 map sensor signal out of range, low
    35 idle air control sensor circuit fault
    36 ignition system circuit error
    38 brake input circuit fault
    39 clutch input circuit fault
    41 cam sensor circuit fault, igntion control circuit fault
    42 electronic spark timing (EST) circuit grounded
    43 knock sensor
    or electronic spark control circuit fault
    44 oxygen sensor lean exhaust
    45 oxygen sensor rich exhaust
    46 pass-key II circuit or ps.pressure switch circuit fault
    47 pcm-bcm data circuit
    48 misfire diagnosis
    51 calibration error, mem-cal, ecm or eeprom failure
    52 engine oil temperature circuit, low temperature indicated
    53 battery voltage error or egr or pass-key II circuit
    54 egr system failure or fuel pump circuit low voltage
    55 a/d converter error or pcm not grounded or lean fuel or frounded reference voltage
    56 quad-driver module #2 circuit
    57 boost control problem
    58 vehicle anti-theft system fuel enable circuit
    61 a/c system performance or degraded oxygen sensor signal
    62 engine oil temperature high temperature indicated
    63 oxygen sensor right side circuit open or map sensor out of range
    64 oxygen sensor right side lean exhaust indicated
    65 oxygen sensor right side rich exhaust indicated
    66 a/c pressure sensor circuit low pressure
    67 a/c pressure sensor circuit or a/c clutch circuit failure
    68 a/c compressor relay circuit failure
    69 a/c clutch circuit head pressure high
    70 a/c refrigerant pressure circuit high
    71 a/c evaporator temperature sensor circuit low
    72 gear selector switch circuit
    73 a/c evaporator temperature circuit high
    75 digital egr #1 solenoid error
    76 digital egr #2 solenoid error
    77 digital egr #3 solenoid error
    79 vehicle speed sensor (vss) circuit signal high
    80 vehicle speed sensor (vss) circuit signal low
    81 brake input circuit fault
    82 ignition control (IC) 3X signal error
    85 prom error
    86 analog/digital ecm error
    87 eeprom error
    99 power management
  2. Johan King

    Johan King New Member

    On obd1 cars you need to change the chip inside the computer, call summit racing or Jeggs to see if one is offered for your engine.
  3. eagle542807

    eagle542807 New Member

    anybody got the codes for the 98 GMC 1500 5.7 ... Just asking Thanks Guys. More Checy to ya!
  4. eagle542807

    eagle542807 New Member

    :rules: Do you have the codes for the 98 GMC 5.7 Vortec
  5. likeArock

    likeArock New Member

    Cool, thanks
  6. wis bang

    wis bang New Member 100 Posts

    '96 & up is OBD II and you need a reader to get them...OBD I you could get w/ a paper clip by making the CES lamp flash 'em...google GM OBD II Codes
  7. auzivision

    auzivision New Member

    So this ODB ‘scanner’ I bought years ago is just a paper clip in disguise???

    [​IMG]

    That’s too funny… at least having the book with all the codes comes in handy!
  8. jackal

    jackal New Member

    A friend of mine just got back from Autozone...They can't scan the OBD 1 vehicles anymore because their scanner doesn't work on them...ha ha...so I whipped out my scanner (paperclip) and did it for him...too funny.
  9. Wenzler383

    Wenzler383 New Member

    I just got a 1992 C1500, 4.3, with a 5-speed. Every once in a while the check engine light comes on, usually after driving on the freeway, and when I turn the truck off the light doesn't come back on. I went out and bought an OBD1 reader for it, problem is that the truck has to be be off to read the code, and as I previously stated, it stops throwing the code as soon as I turn the truck off. The EGR is plugged off, there's a small leak from the oil sending unit and the truck has 289,000miles and the original cat(OBD1 so no after cat O2 sensor.) Any ideas or suggestions?
  10. greg1944

    greg1944 New Member

    The E C M has a memorie, but you need a Pro reader to re-trive it! My reader cost me $2000 10 years ago! Expensive paper clip!

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