how do I find what 'byte number' corresponds to A/Cpres $DA2

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dizwiz24
Posts: 55
Joined: Mon Jun 29, 2009 6:15 pm

how do I find what 'byte number' corresponds to A/Cpres $DA2

Post by dizwiz24 »

Hi

How would I find out what 'byte #' corresponds to the A/C pressure output on a $DA2 tune? 93 corvette

I have never been thru/ dont know how to read the actual 'code'.

I am datalogging my wideband o2 sensor thru my A/C pressure transducer such that it shows up alongside (referenced) to my other operating conditions.

Any help is appreciated!
cbernhardt
Posts: 95
Joined: Fri Apr 18, 2008 5:19 am

Post by cbernhardt »

I am not familiar with the $DA2 tune, but here is some information that may help, a link to a webpage that I created when I was datalogging my wide band with an MEFI4a controller. Does your wide band have an analog output?
http://www.carols62.com/ramjet/wideband.html
robertisaar
Author of Defs
Posts: 962
Joined: Sat Feb 21, 2009 3:18 pm
Location: Camden, MI

Post by robertisaar »

does your ADX have an A/C pressure value in the datastream already?
User avatar
Mangus
TunerPro Author
Posts: 1918
Joined: Wed Mar 19, 2003 1:49 pm

Post by Mangus »

It's spec A172. See byte 20 (which is 1-based below, so in your ADX, it should be 19). Malfunction flags are in byte 7.

Code: Select all



                        DATA STREAM A172  SPECIFICATION

       SPECIFICATIONS FOR  DATA STREAM INFORMATION
       -------------------------------------------

       ENGINE   USAGE:
              5.7L MFI H.O. LT1 (VIN = P) 1992 1Y CAR
              5.7L MFI H.O. LT1 (VIN = P) 1993 1Y 1,2F
       DATA PIN  : READ DATA ON PIN "M" OF ALDL CONNECTOR

       BAUD RATE : 8192 BAUD - BI - DIRECTIONAL


        MODE 0 (INPUT MESSAGE)
                ALDL REQUEST:
                - MESSAGE ID     = $F4
                - MESSAGE LENGTH = $56
                - MODE           = $00
                - SUM CHECK

                ECM RESPONSE: THE ECM WILL TRANSMIT THE FOLLOWING MESSAGE.
                - MESSAGE ID     = $F4
                - MESSAGE LENGTH = $56
                - MODE           = $00
                - SUM CHECK

        MODE 1 (TRANSMIT FIXED DATA STREAM) MESSAGE 0
                ALDL REQUEST:
                - MESSAGE ID     = $F4
                - MESSAGE LENGTH = $57
                - MODE           = $01
*               - MESSAGE        = $00
                - SUM CHECK

                THE ECM WILL RESPOND WITH THE FOLLOWING MESSAGE:
                - MESSAGE ID     = $F4
                - MESSAGE LENGTH = $95
                - MODE           = $01
                - DATA BYTE 1
                  .
                  .
                - DATA BYTE 63
                - SUM CHECK




        MODE 10 (CLEAR MALFUNCTION CODES)
                ALDL REQUEST:
                - MESSAGE ID     = $F4
                - MESSAGE LENGTH = $56
                - MODE           = $0A
                - CHECKSUM





ALDL DATA LIST
NUMBER OF DATA WORDS - 63
ALDL MODE 1 DATA LIST
WORD #   DATA NAME            DESCRIPTION
  1      PROMIDA      PROMID (MSB)
  2      PROMIDA+1    PROMID (LSB)
                        ID = (MSB * 256 + LSB)
  3      MALFFLG1      MALFUNCTION WORD 1
         0      CODE 23     MAT SENSOR LOW
         1      CODE 22     THROTTLE SENSOR POSITION LOW
         2      CODE 21     THROTTLE SENSOR POSITION HIGH
         3      CODE 16     LO RES. PULSE FAILURE
         4      CODE 15     COOLANT SENSOR LOW TEMPERATURE
         5      CODE 14     COOLANT SENSOR HIGH TEMPERATURE
         6      CODE 13     LEFT OXYGEN SENSOR FAILED
         7      CODE 12     NO REFERENCE PULSES
  4      MALFFLG2      MALFUNCTION WORD 2
         0      CODE 34     MAP SENSOR LOW
         1      CODE 33     MAP SENSOR HIGH
         2      CODE 32     EGR DIAGNOSTIC
         3      CODE 28     QDM #3
         4      CODE 27     QDM #3
         5      CODE 26     QDM #3
         6      CODE 25     MAT SENSOR HIGH
         7      CODE 24     VEHICLE SPEED SENSOR
  5      MALFFLG3      MALFUNCTION WORD 3
         0      CODE 51     PROM ERROR
         1      CODE 46     FUEL ENABLE FAILURE
         2      CODE 45     LEFT OXYGEN SENSOR RICH
         3      CODE 44     LEFT OXYGEN SENSOR LEAN
         4      CODE 43     ESC FAILURE
         5      CODE 42     EST GROUNDED
         6      CODE 41     EST OPEN
         7      CODE 36     HI RES. PULSE FAILURE
  6      MALFFLG4      MALFUNCTION WORD 4
         0      CODE 63     RIGHT OXYGEN SENSOR FAILURE
         1      CODE 62     OIL TEMPERATURE SENSOR HIGH
         2      CODE 61     C.V. IV A/C COMPRESSOR FAULT
         3      CODE 56     NOT USED
         4      CODE 55     FUEL LEAN MALFUNCTION
         5      CODE 54     NOT USED
         6      CODE 53     SYSTEM VOLTAGE PROBLEM
         7      CODE 52     OIL TEMPERATURE SENSOR LOW
  7      MALFFLG5      MALFUNCTION WORD 5
         0      CODE 72     GEAR SWITCH FAILURE
         1      CODE 71     A/C EVAPORATOR TEMP SENSOR FAILURE
         2      CODE 69     A/C CLUTCH CIRCUIT OPEN
         3      CODE 68     A/C RELAY SHORTED
         4      CODE 67     A/C PRESSURE TRANSDUCER DEGRADED
         5      CODE 66     A/C PRESSURE TRANSDUCER OPEN OR SHORTED
         6      CODE 65     RIGHT OXYGEN SENSOR RICH
         7      CODE 64     RIGHT OXYGEN SENSOR LEAN

  8      TCCMW         TCC MODE WORD
         0      1 = TCC LOCKED
         1      1 = KCOASTS COAST RELEASE TPS THRESHOLD IN USE (HI MPH)
         2      1 = 4-3/4-2 DOWNSHIFT RELEASE IN PROGRESS
         3      1 = STATUS OF FOURTH GEAR LAST PASS
         4      1 = TCC LOCKED FOR PASS-BY NOISE
         5      1 = 1-2 UPSHIFT IN PROGRESS
         6      1 = 2-3 UPSHIFT IN PROGRESS
         7      1 = IN FOURTH GEAR
  9      NVMW2         NON - VOLITILE MODE WORD
         0      NOT USED
         1      1 = CLOSED LOOP (FUEL) TIMER TIMED OUT
         2      NOT USED
         3      1 = PLUGGABLE MEMORY FAILURE (M51)
         4      NOT USED
         5      1 = FUEL ENABLED VIA FEDS OR FREQUENCY
         6      NOT USED
         7      1 = ESC ENABLED BY DELTA COOLANT
  10     CARSMW        MODE FOR COMPUTER AIDED RATIO SELECTION LOGIC
         0      1 = CARS DISABLED DUE TO LOW BAROMETRIC PRESSURE
         1      1 = CARS ACTIVE
         2      NOT USED
         3      NOT USED
         4      1 = TRANSMISSION IN FOURTH GEAR
         5      1 = TRANSMISSION IN FIRST GEAR
         6      1 = WAIT FOR VEHICLE SPEED RESET
         7      1 = TRANSMISSION IN SECOND GEAR
  11     IODPORTC      IOD PORT C OUTPUT CONTROL WORD
         0      1 = IN DRIVE    (0 = P/N)
         1      1 = IN 3RD OR 4TH GEAR
         2      0 = IN 4TH GEAR
         3      1 = IN LOW, 3RD, OR 4TH GEAR
         4      1 = PSPS NOT CRAMPED (NOT USED)
         5      1 = A/C CLUTCH ENGAGED
         6      0 = A/C REQUESTED (Y - CAR)
         7      0 = TRACTION CONTROL ACTIVE
  12     IODPORTB      IOD PORT B INPUT DATA/OUTPUT CONTROL WORD
         0      1 = CHECK ENGINE LIGHT ON
         1      1 = QDM FAULT 1 NOT INDICATED
         2      1 = QDM FAULT 2 NOT INDICATED
         3      1 = QDM FAULT 3 NOT INDICATED
         4      1 = SXR TRANSMISSION ENABLED
         5      1 = C.A.R.S. LIGHT ON
         6      1 = D, R CAR A/C REQUEST (Y-CAR OPTION NOT SELECTED)
         7      1 = NOT USED
  13     MW1           MODE WORD 1
         0      1 = FIRST REFERENCE PULSE HAS BEEN DETECTED
         1      1 = IDLE SPARK HIGH GAIN MODE ENABLED
         2      1 = IDLE SPARK LOW GAIN MODE ENABLED
         3      1 = UNDERSPEED (USED BY IDLE SPARK LOGIC)
         4      1 = ROAD SPEED 1ST PULSE DETECTED
         5      0 = A/C CLUTCH ON
         6      1 = 1ST SPI ERROR DETECTED (2ND IS FATAL)
         7      1 = ENGINE RUNNING (SPARK)

  14     MW2           MODE WORD 2
         0      1 = MORE THAN 100 MSECS. FOR SPI MESSAGE TO COMPLETE
         1      1 = RUN SPARK ENABLED
         2      1 = REFERENCE PULSE OCCURRED (6.25 MSEC. CHECK)
         3      1 = ELITE DELAY STARTED
         4      0 = REVERSE INHIBITED (F-CAR ONLY)
         5      1 = A/C DISABLED DUE TO COMPRESSOR FAULT DETECTED
         6      1 = HIGH BATTERY VOLTAGE
         7      1 = USE LO A/C OFF EVAP. TEMP THRESH DUE TO WARM START

  15     PORTASD       PORT A DATA REGISTOR
         0      FUEL TRIGGER
         1      LOW RESOLUTION REFERENCE PULSE INPUT
         2      EST FEEDBACK
         3      INJECTOR 2 FAULT
         4      INJECTOR 1 FAULT
         5      INJECTOR DRIVER 1
         6      INJECTOR DRIVER 2
         7      SPI HANDSHAKE LINE
  16     LCCPMW        LCC & CCP MODE WORD
         0      1 = CCP ENABLED
         1      1 = CCMREVS FLIP-FLOP
         2      1 = MALFS HAVE OCCURRED
         3      1 = ALDL MODE 4 BYPASS FUEL COMMANDED
         4      SECOND TIME COOLANT
         5      1 = FALSE REFERENCE PULSE DETECTED
         6      1 = KWARM KICKDOWN REQUESTED
         7      1 = CLOSED THROTTLE SPARK ACTIVE
  17     DIAGMW5       DIAGNOSTIC MODE WORD 5
         0      1 = REFERENCE PULSE OCCURRED THIS 100 MSECS. (M36 LOGIC)
         1      1 = MALF 41 (OPEN EST) DETECTED
         2      1 = MALF 42 (GROUNDED EST) DETECTED
         3      1 = MALF 16 FIRST PASS HAS OCCURRED
         4      NOT USED
     *   5      1 = MALF 43A PRESENT (ONE ESC SENSOR OPEN)(not used in f-car)
     *   6      1 = MALF 43C PRESENT (BOTH ESC SENSORS OPEN) Y-CAR ONLY
                1 = MALF 43C PRESENT (ESC SENSOR OPEN) F-CAR ONLY
     *   7      1 = MALF 43D PRESENT (BOTH ESC SENSORS GROUNDED) Y-CAR ONLY
                1 = MALF 43D PRESENT (ESC SENSOR GROUNDED) F-CAR ONLY
  18     AIRMW         MAJOR LOOP MODE WORD
         0      1 = IAC MOTOR MOVING (LAST PASS)
         1      1 = AIR TO PORTS OR CONVERTER,   0 = AIR DEVERTED
         2      1 = AIR TO EXHAUST PORTS,        0 = AIR TO CONVERTER
         3      1 = IAC MOTOR RESET PREVIOUSLY VIA SLEWING
         4      1 = A/C REQUESTED (F - CAR)
         5      1 = IAC MOTOR EXTENDING          (0 = RETRACTING)
         6      1 = LAST 3.125 MSEC. IRQ WAS IAC 320 HZ INTERRUPT
         7      1 = DECEL ENLEANMENT ENABLED

  19     MWFA1         FUEL - AIR MODE WORD
         0      1 = AIR DIVERTED
         1      1 = LEARN CONTROL ENABLED
         2      1 = LOW RPM HYSTERESIS FLAG IN CRANKING
         3      1 = LEFT BANK BLM CHANGE INTEGRATOR RESET FLAG
         4      1 = RIGHT BANK BLM CHANGE INTEGRATOR RESET FLAG
         5      NOT USED
         6      1 = CATALYTIC CONVERTER OVERTEMP ENABLED
         7      1 = ENGINE IS CLOSED LOOP (BOTH SENSORS C.L.)

  20     ADACPRES    A/D RESULT FOR A/C PRESSURE TRANSDUCER
                      PSI = (N * 1.875)-18.75

  21     DIAGMW3       DIAGNOSTIC MODE WORD 3
         0      1 = INTEGRATORS BEING FORCED TO 128 (USED IN M32)
         1      MALF 44 OR 45 HAS BEEN DETECTED
         2      1 = BYPASS O2 MALF LOGIC - INT. BEING RESET
         3      1 = M53 ACTIVE &#40;VOLTAGE > 17 OR VOLTAGE < 8&#41;
         4      1 = MALF 13 DETECTED
         5      1 = IN DIAGNOSTIC MODE LAST PASS &#40;FOR NVM CLEAR&#41;
         6      1 = MALF 36 INDICATED AND LATCHED &#40;HI REF. FAULT&#41;
         7      1 = DIAGNOSTIC MODE HAS BEEN ENTERED

  22     COOLDEGA    COOLANT TEMPERATURE LINEARIZED  &#40;NON-DEFAULTED&#41;
                     DEGREES C = &#40;N*.75 - 40&#41;
                     DEGS. F = &#40;1.35N - 40&#41;
  23     ADMAP       A/D RESULT FOR MANIFOLD PRESSURE SENSOR INPUT
                      VOLTS = N*5/256
                      &#40;kpa = &#40;N + 28.06&#41;/2.71&#41;
  24     ADTHROT     A/D RESULT FOR TPS INPUT
                      VOLTS = N*&#40;5/256&#41;
  25     ADBAT       A/D RESULT FOR IGNITION VOLTAGE INPUT
                      VOLTS = N/10
  26     ADOILTMP    A/D RESULT FOR OIL TEMPERATURE SENSOR INPUT
                     SEE OIL TEMP. LOOK-UP TABLE &#40;NON-DEFAULTED&#41;
  27     NVADBARO    NON - VOLITILE COMPUTED A/D BAROMETER
                      VOLTS = N*&#40;5/256&#41;
                      KPA = &#40;N + 28.06&#41;/2.71&#41;
  28     ADMAT       A/D RESULT FOR MANIFOLD TEMPERATURE INPUT
                      SEE MAT LOOK-UP TABLE  &#40;DEFAULTED&#41;
  29     ADLO2       A/D RESULT FOR LEFT O2 SENSOR INPUT
                      MV = N*4.42
  30     ADRO2       A/D RESULT FOR RIGHT O2 SENSOR INPUT
                      MV = N*4.42
  31     LBLM        LEFT BANK BLOCK LEARN MULTIPLIER
                      N = COUNTS
  32     RBLM        RIGHT BANK BLOCK LEARN MULTIPLIER
                      N = COUNTS
  33     BLMCELL     BLOCK LEARN MULTIPLIER CELL NUMBER
                      N = NUMBER
  34     RESETCTR    RESET COUNTER FOR MALF 51

  35     CYLSD       COPY OF LOWER BYTE OF CYL SERIAL DATA

  36     LINT        INTEGRATOR VALUE FOR LEFT O2 SENSOR
                      N = COUNTS
  37     RINT        INTEGRATOR VALUE FOR RIGHT O2 SENSOR
                      N = COUNTS
  38     ISMNMPKA    KEEP - ALIVE IAC MINIMUM MOTOR POSITION
                      N = IAC STEPS
  39     PURGEDC     PURGE DUTY CYCLE
                      % DC = N/2.56
  40     ISSPMP      IAC PRESET MOTOR POSITION
                      N = IAC STEPS
  41     ISESDD      DESIRED IDLE SPEED
                      RPM = N * 12.5
  42     NEWRFPER    PRESENT MINOR LOOP REFERENCE PERIOD &#40;MSB&#41;
  43     NEWRFPER+1  PRESENT MINOR LOOP REFERENCE PERIOD &#40;LSB&#41;
                      MSEC = &#40;MSB*256 + LSB&#41;/65.536
  44     SAREF       LIMITED SPARK RELATIVE TO REF. PULSE
                      DEGREES = N
  45     ADACEVAP    A/D RESULT FROM A/C EVAPORATOR TEMP.
                     SEE A/C LOOK-UP TABLE
  46     NTRPMX      ENGINE SPEED
                      RPM = N * 25
  47     TIME        ENGINE RUNNING TIME IN SECONDS &#40;MSB&#41;
  48     TIME+1      ENGINE RUNNING TIME IN SECONDS &#40;LSB&#41;
                      SECONDS = &#40;MSB*256 + LSB&#41;
  49     NOCKRTD     RETARD DUE TO KNOCK
                      DEGREES = N/2
  50     OLDESCCT    ECU ESC COUNTER VALUE FROM LAST MINOR LOOP &#40;MSB&#41;
  51     OLDESCCT+1  &#40;LSB&#41; NOT USED
                      N = &#40;MSB&#41;
  52     MPH         VEHICLE SPEED
                      MPH = N
                      KPH = &#40;1.61 * N&#41;
  53     NTPSLD      THROTTLE LOAD AXIS VARIABLE
                      % THROTTLE = N/2.56
  54     ACTVOL36    100 MSEC . OLD HI RES. PULSE COUNT &#40;M36 LOGIC&#41; &#40;MSB&#41;
  55     ACTVOL36+1  100 MSEC . OLD HI RES. PULSE COUNT &#40;M36 LOGIC&#41; &#40;LSB&#41;

  56     LBPINJC      LEFT BANK LOW VOLTAGE CORRECTED BPW &#40;MSB&#41;
  57     LBPINJC+1    LEFT BANK LOW VOLTAGE CORRECTED BPW &#40;LSB&#41;
                        MSECS. = &#40;MSB * 256 + LSB&#41;/131
  58     RBPINJC      RIGHT BANK LOW VOLTAGE CORRECTED BPW &#40;MSB&#41;
  59     RBPINJC+1    RIGHT BANK LOW VOLTAGE CORRECTED BPW &#40;LSB&#41;
                        MSECS. = &#40;MSB * 256 + LSB&#41;/131
  60     REFPERSD     COPY OF REFPER FOR SERIAL DATA &#40;MSB&#41;
  61     REFPERSD+1   COPY OF REFPER FOR SERIAL DATA &#40;LSB&#41;
                        MSECS. = &#40;MSB * 256 + LSB&#41;/65.535
  62     EGRDC        EGR DUTY CYCLE
                        DC = N/2.56

  63     FANMW         FAN CONTROL MODE WORD
         0      1 = FAN 1 ENABLED &#40;ALL PID FAN 1 STEPS ADDED&#41;
         1      1 = SPI FAILED &#40;USED FOR ALDL&#41;
         2      1 = FAN 1 REQUESTED
         3      1 = FAN 2 ENABLED &#40;ALL PID FAN 2 STEPS ADDED&#41;
         4      1 = FAN 2 REQUESTED
         5      1 = FAN 1 ENABLED BY HIGH OIL TEMPERATURE
         6      1 = HIGH RPM FAN ENABLE
         7      1 = NOT USED

***************************************
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1989 Trans Am
dizwiz24
Posts: 55
Joined: Mon Jun 29, 2009 6:15 pm

Post by dizwiz24 »

thanks!
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