Allante V8-273 4.5L (1991)
Engine Control Module: Scan Tool Testing and Procedures
When troubleshooting a malfunction, the PCM/ECM and BCM data display can be used to compare the vehicle with problems to a vehicle which is
functioning property.
A brief summary of each parameter is provided below:
EDO1 The Throttle Position Sensor (TPS) is displayed in degrees from -9° to 90°.
ED02
The Manifold Air Pressure Sensor (MAP) is displayed in kilopascals (kPa) from 14 to 108.
ED03
The Computed Barometric pressure (BARO) is displayed in kilopascals (kPa) from 60 to 102. The BARO reading is taken at key ON and is
corrected at WOT.
ED04
The coolant temperature is displayed in degrees Celsius (°C) from -40° to 151°.
ED05
The Manifold Air Temperature Sensor (MAT) also called Air Temperature Sensor is displayed in degrees Celsius (°C) from -40° to 151°.
ED08
The spark advance display shows timing advance in degrees Before Top Dead Center (BTDC) as generated by the EST signal from the
PCM/ECM from 0 to 90 degrees. If base timing is properly adjusted (10 degrees BTDC) the readings from a timing meter or timing light
should agree.
ED1O The battery voltage is read in volts, from 0 to 25.6. This is the voltage measured at the fuel pump feed back at terminal F1.
ED11
The engine speed is displayed in RPM from 0 to 6370.
ED12
The vehicle speed is displayed in Miles Per Hour (MPH) from 0 to 255.
ED19
The power steering pressure sensor shows pressure in kPa from 0 to 9961.
ED30
The left injector pulse width display shows pulse width in milliseconds (ms) form 0 to 99.6.
ED31
The right injector pulse width display shows pulse width in ms from 0 to 99.6.
ED32
The left oxygen sensor voltage is displayed in volts from 0 to .99.
ED33
The right oxygen sensor voltage is displayed in volts from 0 to .99.
ED34
The left oxygen sensor cross counts displays counts from 0 to 255. The cross count is the number of times the voltage crosses the reference
voltage of .45 volts in one second.
ED35
The right oxygen sensor cross counts displays counts from 0 to 255. The cross count is the number of times the voltage crosses the reference
voltage of .45 volts in one second.
ED36
The left fuel integrator displays counts from 0 to 255. The normal count position for the integrator is 128, and indicates that the engine is
operating normally. A count greater than 128 indicates that time is being added to the injector pulse width, which adds more fuel to the engine.
A count less than 128 indicates time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine.
ED37
The right fuel integrator displays counts from 0 to 255. The normal count position for the integrator is 128, and indicates that the engine is
operating normally. A count greater than 128 indicates that time is being added to the injector pulse width, which adds more fuel to the engine.
A count less than 128 indicates time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine.
ED38
The left Block/Learn (B/L) displays counts from 0 to 255. The normal count position for the B/L is 128 and indicates that the engine is
operating normally. The B/L value is based on integrator learned values. It is stored in memory blocks of the long term memory according to
MAP and RPM values. A count greater than 128 indicates that time is being added to the injector pulse width, which adds more fuel to the
engine. A count less than 128 indicates time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine.
ED39
The right Block/Learn (B/L) displays counts from 0 to 255. The normal count position for the B/L is 128 and indicates that the engine is
operating normally. The B/L value is based on integrator learned values. It is stored in memory blocks of the long term memory according to
MAP and RPM values. A count greater than 128 indicates that time is being added to the injector pulse width, which adds more fuel to the
engine. A count less than 128 indicates time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine.
ED70
The cruise control feedback display shows the percentage of servo apply as measured by the servo position sensor with 0 equaling full relaxed
(no vacuum) and 99 equaling full apply (full vacuum signal).
ED71
This display showing 00 indicates that the 2nd gear pressure switch is closed. Display showing 01 indicates that the 2nd gear pressure switch is
