Data Displays

Data Displays
Data displays are operated as detined under "C". Selecting the Test" under the heading ,"How to Operate Service Mode". When troubleshooting a malfunction, the ECM and BCM data display can be used to compare the vehicle with problems to a vehicle which is functioning properly. A brief summary of each parameter is provided below:

ECM:
EDO1 - The THROTTLE POSITION (TPS) is displayed in millivolts (mv) from 0 to 5100.

EDO4 - The COOLANT TEMPERATURE is displayed in degrees Celsius (°C) from -40 to 151.

EDO5 - The MANIFOLD AIR TEMPERATURE (MAT) also called Air Temperature Sensor is displayed in degrees Celsius (°C) from -40 to 151.

ED06 - The INJECTOR PULSE WIDTH is displayed in Milliseconds (MS), from 0 to 1002.

EDO7 - The OXYGEN SENSOR VOLTAGE is displayed in Millivolts (mv~ from 0 to 1128 my.

EDO8 - The SPARK ADVANCE value is displayed in degrees, from 0 to 70.

ED09 - The TORQUE CONVERTER CLUTCH (TCC) is displayed as a 1 if the ECM is commanding the TCC to engage or a 0 if the ECM is commanding the TCC off. Actual operation depends on the integrity of the TCC system.

ED1O - The BATTERY VOLTAGE is read in volts, between 0 and 25.5.

ED11 - The ENGINE SPEED is displayed in RPM from 0 to 6375.

ED12 - The VEHICLE SPEED is displayed in Miles Per Hour (MPH) from 0 to 159.

ED15 - The OPERATING MODE is displayed as a 1 if the ECM is operating in closed loop (CL) or a 0 if the ECM is operating in open loop (OL).

ED16 - The Knock Retard (ESC) is displayed in degrees of timing pulled out, from 0 to 45.

ED17 - The KNOCK SENSOR ACTIVITY (OLD PA3) is displayed as counts. This counter changes whenever the ESC line is LO, which indicates sensor activity (detonation).

ED18 - The OXYGEN SENSOR CROSS COUNTS is displayed as the number of times the 02 sensor crossed the reference line each second.

ED19 - The FUEL INTEGRATOR is displayed in counts, from 0 to 255.

ED2O - The BLOCK LEARN MULTIPLIER (BLM) is displayed in counts, from 0 to 255.

ED21 - The MASS AIR FLOW (MAF) is displayed in grams per second of air flow from 0 to 255.

ED22 - The IDLE AIR CONTROL (IAC) is displayed in steps of travel from 0 to 255.

ED23 - The ENGINE LOAD (LV8) is displayed in counts from 0 to 255.

ED98 - The IGNITION CYCLE COUNTER value is the number of times the ignition has been cycled to "OFF" since an ECM Trouble Code was last detected. After 50 ignition cycles without any malfunction being detected, all stored ECM codes are cleared.

ED99 - The ECM PROM I.D. is displayed as a number up to three digits long which can be used to verify that the proper PROM is installed in the ECM.

BCM:
BD2O - The COMMANDED BLOWER VOLTAGE is read in volts from 0 to system voltage.

BD21 - The COOLANT TEMPERATURE is displayed in degrees Celsius (°C) from - 40 to 151. This value is sent from the ECM to the BCM. If this circuit malfunctions as determined by the ECM, the ECM will send the BCM a "Failsoft" value for display.

BD22 - The COMMANDED AIR MIX DOOR POSITION is displayed in percent (%). A value close to 0% represents a cold air mix and a value close to 100% represents a warm air mix.

BD23 - The ACTUAL AIR MIX DOOR POSITION is displayed in percent (%). This value should follow the commanded air mix door position (BD22) except when the door is commanded beyond its mechanical limits of travel.

BD24 - The AIR DELIVERY MODE is displayed as a number from 0 to 10. Each number is a code which represents the following air delivery modes:
0 = Auto - Recirc/MAX A/C
1 = Auto - A/C (vents)
2 = Auto - Bi - Level
3 = Auto - Heater - Def
4 = Auto - Heater
5 = OFF
6 = Normal Purge
7 = Cold (DEF) Purge
8 = Forced/Def
9 = Forced/Heater
10 = Forced/Bi-Level

BD25 - The IN-CAR TEMPERATURE is displayed in degrees Celsius (°C), from -40 to 102.

BD26 - The ACTUAL OUTSIDE TEMPERATURE is displayed in degrees Celsius (°C), from - 40 to 58. This value represents actual sensor temperature and is not restricted by the features used to minimize engine heat affects on the customer display value.

BD27 - The HIGH SIDE TEMPERATURE (condenser output) is displayed in degrees Celsius (°C) from -40 to 215.

BD28 - The LOW SIDE TEMPERATURE (evaporator input) is displayed in degrees Celsius (°C) from - 40 to 93.

BD32 - The SUNLOAD TEMPERATURE SENSOR is displayed in degrees Celsius (°C) from -23 to 102.

BD4O - The ACTUAL FUEL LEVEL is read in gallons between 0 and 19.0. This value represents actual sensor position and is not restricted by the features used to eliminate fuel slosh affects on the customer display value.

BD42 - The DIMMING POT is displayed in percent (%). A value close to 0% represents maximum dimming and a value close to 100% represents maximum brightness.

BD43 - The TWILIGHT DELAY POT is displayed in percent (%). A value close to 0% represents minimum delay time and a value close to 100% represents maximum delay time.

BD44 - The TWILIGHT PHOTOCELL is displayed in percent (%). A value close to 0% represents daylight and value close to 100% represents darkness.

BD5O - The BATTERY VOLTAGE is read in volts between 0 and 25.5.

BD51 - The GENERATOR FIELD is displayed in percent (%). A value close to 0% represents minimum regulator on time and a value close to 100% represents maximum regulator on time.

BD6O - The VEHICLE SPEED is displayed in miles per hour (MPH) from 0 to 159.

BD61 - The ENGINE SPEED is displayed in RPM from 0 to 6375.

BD7O - The CRUISE SERVO POSITION is displayed in percent (%) from 0 to 100. A value close to 0% represents rest position and a value close to 100% represents W.O.T.

BD71 - The OIL PRESSURE SENSOR is displayed in pressure (PSI) from 0 to 80.

BD98 - The IGNITION CYCLE value is the number of times that the ignition has been cycled to "OFF" since a BCM Trouble Code was last detected. After 50 ignition cycles without any malfunction being detected, all BCM codes are cleared.

BD99 - The BCM PROM I.D. is displayed as a number, up to four digits long, which can be used to verify that the proper PROM was installed in the BCM.

Input Displays
Input displays are operated as defined under "C". Selecting the Test" under the heading "How to Operate Service Mode". When trouble shooting a malfunction, the ECM, BCM, or IPC input display can be used to determine if the switched inputs can he properly interpreted.

When one of the various input tests is selected, the state of that device is displayed as HI or LO. In general, the Hi and LO refer to the input terminal voltage for that circuit. The display also indicates if the input changed state so that the technician could activate or deactivate any listed device and return to the display to see if it changed state. If a change of state occurred, an "X" will appear next to the Hi/LO indicator, otherwise a "0"will remain displayed. The "X" will only appear once per selected input, although the HI/LO indication will continue to change as the input changes. Some tests are momentary and the "X" can be used as an indication of a change. The following is a list of ECM, BCM and IPC inputs:

ECM:
E160 - The EVRV display is "LO" when the EGR is On.

EI74 - The PARK-NEUTRAL (P-N) display is "LO" when the vehicle is in Park or Neutral.

EI78 - The POWER STEERING PRESSURE SWITCH display is "LO" when power steering pressure (effort) is high, wheel in cramp position.

EI82 - The FOURTH GEAR SWITCH is "HI" when the vehicle is in fourth gear.

BCM:
BIO1 - The COURTESY LAMP PANEL SWITCH display is "LO" when courtesy lights are on from switch.

BI02 - The PARK LAMP SWITCH display is "LO" when the parklamp switch is in the off position.

BI03 - The DRIVER DOOR AJAR SWITCH display is "LO" when the driver's door is ajar.

BI04 - The PASSENGER DOOR AJAR SWITCH display is "LO" when the passenger door is ajar.

BI05 - The DOOR JAMB SWITCH display is "LO" when the driver's or passenger's door is open.

BI06 - The DOOR HANDLE SWITCH display is momentarily "LO" when either outside door handle button is depressed.

BI08 - The LOW REFRIGERANT PRESSURE SWITCH display is "LO" when the system is low on refrigerant.

BI09 - The WASHER FLUID LEVEL SWITCH display is "LO" when the vehicle is low on washer fluid.

BI10 - The LOW COOLANT LEVEL display is "LO" when the engine is low on coolant.

B116 - The KEY IN IGNITION display is "LO" only when the key is in the "LOCK" position. (Cannot be seen as diagnostics do not work with key off, therefore, should always read "HI").

B119 - The LOW VACUUM SWITCH display is "LO" when vacuum supply is low.

B121 - The LOW BRAKE FLUID display is "LO" when brake fluid level is low.

B122 - The PARK BRAKE SWITCH display is "LO" when the parking brake is ON.

B124 - The REVERSE GEAR SWITCH display is "HI" only when the vehicle is in reverse.

B125 - The SEAT BELT SWITCH display is "HI" when the driver's seatbelt is fastened.

B126 - The OIL PRESSURE SWITCH display is "LO" when oil pressure Is low.

B151 - The GENERATOR FEEDBACK display is "LO" when there is an GENERATOR problem (or engine not running).

B171 - The CRUISE CONTROL BRAKE SWITCH display is "Hi" when the cruise ON/OFF switch is "ON" and the brake pedal is not depressed (free state).

B17.5 - The CRUISE CONTROL ON/OFF SWITCH display is "HI" when the switch is "ON".

B176 - The CRUISE CONTROL SET/COAST SWITCH display is "HI" when the cruise ON/OFF switch is "ON" and the set/coast switch is depressed.

BI77 - The CRUISE CONTROL RESUME/ACCEL SWITCH display is "HI" when the cruise ON/OFF switch is "ON" and the Resume/Accel switch is depressed.

B178 - The HEADLAMP SWITCH display is "HI" whenever the headlamps are on.

B179 - The HIGH BEAM SWITCH display is as long as the lever is pulled.

B182 - The TWILIGHT ENABLE SWITCH is "LO" whenever the twilight sentinel is turned on.

IPC:
II10 - The REAR DEFOG SWITCH display is "LO" as long as the switch in the right switch assembly is held depressed.

II11 - The FRONT DEFROST SWITCH display is "LO" as long as the switch in the right switch assembly is held depressed.

II15 - The TAIL LAMP OUT display is "HI" when there is a tail lamp out.

II16 - The HEADLAMP OUT display is "HI" when there is a headlamp out.

II17 - The PARKLAMP OUT display is "HI" when there is a parklamp out.

Output Displays
Output displays are operated as defined under "C Selecting the Test" under the heading "How to Operate Service Mode". When troubleshooting a malfunction, the ECM and BCM output cycling can be used to determine if the output tests can be actuated regardless of the inputs and normal program instructions. Once a test in outputs has been selected, except for ECM IAC, the test will display HI and LO for three seconds in each state to indicate the command and output terminal voltage. A brief summary of each output is provided below:

ECM:
EO00 - The NO OUTPUTS display will not display "HI" nor "LO" as this is a resting spot where no outputs will be cycled.

EO01 - The CANISTER PURGE SOLENOID display will he "LO" when the solenoid is on (energized).

EO02 - The TORQUE CONVERTER CLUTCH (TCC) display will be "LO" when the TCC is on (energized).

E004 - The EGR SOLENOID display will be "LO" when the EGR Solenoid is "ON" (energized).

E007 - The IAC MOTOR does not cycle "Hi" or "LO" but instead extends the pintle all the way out and holds it there so minimum air adjustment can be made.

EO08 - The A/C CLUTCH display will be "HI" when the clutch is on (energized).

EO09 - The COOLANT FAN RELAY display is "LO" when the coolant fan is "ON" (energized)

BCM:
BO00 - The NO OUTPUTS display will not display "HI'1 nor "LO" as this is a resting spot where no outputs will be cycled.

BO01 - The CRUISE CONTROL VENT SOLENOID) display is "HI" when the vent solenoid is on (energized). The cruise ON/OFF switch must be on for this output to cycle.

BO02 - The CRUISE CONTROL VACUUM SOLENOID display is "HI" when the vacuum solenoid is on (energized). The cruise ON/OFF switch must be on for this output to cycle.

BO03 - The RETAINED ACCESSORY POWER (RAP) relays display is "LO" when the relays are on (energized).

BO04 - The COURTESY RELAY display is "LO" when the relay is on (energized).

BO05 - The TWILIGHT RELAYS display is "LO" when the relays are on (energized) lights on.

BO06 - The HI/LO BEAM RELAYS display is "LO" when the relays are on (energized) hi beams on.

BO10 - The CHIME 1 display is "LO" when the slow chime is on (sounding).

BO11 - The CHIME 2 display is "LO" when the intermediate chime is on (sounding).

Override Displays
Override displays are operated as defined under "C - Selecting the Test" under the heading "How to Operate Service Mode." When troubleshooting a malfunction, the BCM override feature allows testing of certain system functions regardless of normal program instructions.

Upon selecting a test, that selections current operation will be represented as a percentage of its full range, and this value will be displayed on the CRT below the "Exit" pad.

Touching the pads above or below "OVERRIDE" on the CRT begins the override. Touching the pad above "OVERRIDE" increases the value while the pad below "OVERRIDE" decreases the value. Normal program control can be resumed in one of three ways:
1. Selection of another override test will cancel the current override.
2. Selection of another system will cancel the current override.
3. Overriding the value beyond either extreme (0 or 99) will display "----" momentarily and then jump to the normal program control.

The override test type is unique in that any other test type within the selected system may be active at the same time. After selecting an override test, touching the "EXIT" button will allow selection of another test type, however, the CRT will continue to display the selected override. By selecting another test type and test, and then touching the pads above or below "OVERRIDE", it is possible to monitor the effect of the override on different vehicle parameters.

BS00 - The NO OVERRIDES display will not display any value as this is a resting spot where no overrides will be controlled. This is a handy spot to go to stop the override without having to go back to the level where the system is selected.

BS01 - PROGRAM NUMBER As operating conditions change, the program number will automatically change in response. The automatic calculation of program number can be bypassed by a manual override feature using the pads above and below the word override on the CRT. Touching the pad above override will force the program number to increase at a controlled rate until the value of "99" Is reached "99" represents the "Max Heat" mode of climate control operation. Touching the pad below override will force the program number to decrease until the value of "0" is reached which represents the "MAX A/C" mode. This manual override of automatic program number calculation will continue until the override is stopped. This allows the technician to control the program number to any number from "0" to "99" and simultaneously observe the reaction of any of the BCM data parameters.

BSO2 - VACUUM FLUORESCENT (VF) DIMMING. As the dim pot is moved, the VF Dimming number will automatically change in response (if outside lights are on). The automatic control of dimming can be bypassed by a manual override feature using the pads above and below the word override. "99" represents the max brightness of VF displays and "0" represents the max dimming of VF displays (outside lights do not have to be on to override VF dimming). This allows the technician to control the dimming number to any number from "0" to "99".

BS03 - INCANDESCENT DIMMING As the dim pot is moved the incandescent dimming number will automatically change in response (if outside lights are on). The automatic control of dimming can be bypassed by a manual override feature using the pads above and below the word override. "99" represents the max brightness of incandescent displays and "0" represents the max dimming of incandescent lighting. (Outside lights do not have to be on to override incandescent dimming). This allows the technician to control the dimming number from "0" to "99".

B505 - CRUISE CONTROL The cruise control ON/OFF switch must be on for this test to work. As operating conditions change, the cruise control position number will automatically change in response. The automatic calculation of cruise control position number can be bypassed by a manual override feature using the pads above and below the word override on the CRT. "99" represents the max cruise position (WOT) and "0" represents the minimum cruise position (closed throttle). This manual override of automatic cruise control position number calculation will continue until the override is stopped. This allows the technician to control the cruise control position number to any number from "0" to "99" and simultaneously observe the reaction of the data value for cruise servo position (BD7O). The two should agree with each other ±3% except when the servo is commanded beyond its mechanical limits of travel. Since this test is not allowed with engine running remember that there is usually only enough vacuum in the storage tank to stroke the servo 3 times.