trouble codes and shift problems

[gameover-gjm3]

I have a 1989 pontiac bonneville, the service engine soon light keeps coming on and I dont' have a code reader. Does anyone know where I could get information on pulling the codes and their meaning? Also, it doesn't want to shift out of second gear alot of times, has anyone else run into this problem before? I would appreciate any help you can offer.

Thanks,
GregM

[JimmySLS]

you can go to Autozone and they will pull the codes for you and tell you what they mean..Good luck..

[Hansnet]

Yes there is a way to retrieve codes yourself, but, it only works on models from 1987 - 1993!
Find the "Assembly Line Communication Link (ALCL)" it usually found under the dash near the steering column. Now locate terminals "A" & "B", the 2 uppermost right-hand terminals, "A" is the one the right. You must use a short wire to ground out these terminals, or a hairclip, paperclip, or something similar. Short the terminals with the ignition off, then turn the ignition to "on" but do not start the car. The ECM will display "Code 12" by flashing the "Service Engine Soon" light indicating the system is working. Code 12 is simply one flash, followed by a brief pause, then two flashes in quick succession. This code will flash three times. If no codes are stored code 12 will continue to flash until the ground is removed from the terminal.
After flashing three times, the ECM will display any stored trouble codes. Each code will be flashed three times then code 12 will be flashed again indicating display is completed.
Note: If the trouble is intermittent the engine light will come for about ten seconds then go out. If the trouble is more serious then the engine light will stay on and the trouble codes stored in the ECM memory until voltage is interrupted to the ECM. To clear the codes, disconnect the battery for about ten minutes.

Note: If you or anyone else has disassembled the lower footwell shield (with the diagnostic connector and courtesy light in it) it is possible the connector was reinstalled upside down. In this case, the uppermost right 2 terminals are no longer A nd B! No damage will be incurred if you short these two in this instance, but you will get no codes. If this happens, try the bottom 2 terminals on the left side!

CODES:
code 12: Diagnostic
code 13: Oxygen sensor(open or shorted circuit)
code 14: Coolant sensor circuit (high temp)
code 15: Coolant sensor circuit (low temp)
code 16: System voltage high or low
code 17: Spark reference circuit
code 18: Cam/Crank error
code 21: Throttle position(TPS)voltage high
code 22: Throttle position(TPS)voltage low
code 23: Intake air temperature(IAT)sensor low temp indicated
code 24: Vehicle speed sensor circuit
code 25: Intake air temperature(IAT)sensor high temp indicated
code 26: Quad driver module "A" Circuit
code 27: Gear switch diagnosis
code 28: Same as code 27
code 29: Same as code 27
code 31: Park/Neutral switch
code 32: EGR system
code 33: MAF sensor-voltage too high
code 34: MAF sensor-voltage too low
code 36: Transaxle shift problem
code 38: Brake input circuit
code 39: Torque converter clutch(TCC)problem
code 41: Cam sensor circuit loss of signal
code 42: Electronic spark control circuit
code 43: Electronic spark control circiut or Knock sensor problem
code 44: O2 sensor-Lean exhaust indicated
code 45: O2 sensor-Rich exhaust indicated
code 46: Power steering pressure switch
code 48: Misfire diagnosis
code 51: Prom or MEM-CAL error
code 52: CAL-PAK faulty,missing or installed wrong
code 55: ECM
code 56: Boost control solenoid
code 63: EGR flow check
code 64: Same as code 63
code 65: same as code 63

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