Allante V8-273 4.5L (1991)
Engine Control Module: Initial Inspection and Diagnostic Overview
Overrides
The PCM/ECM override feature allows testing of certain system functions regardless of normal program instructions. Upon selecting a test, the current
operation of that function will be displayed as a percentage of its full range on the ECC panel. The display will alternate between "--" for 1 second
followed by the normal program command for 10 seconds. This alternating display is a reminder that the function is not currently being overridden.
Pressing the Warmer or Cooler buttons on the ECC panel initiates the override at which time the display will no longer alternate to "--".
Pressing the Warmer button increases the override value while pressing the cooler button decreases the override value. Upon release of the button, the
display may either remain at the overridden value or automatically return to normal program control. This depends on which function is being overridden
at the time.
If the display remains at the override 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 (i.e. PCM/ECM to BCM) will cancel the current override.
3.
On some system overrides, overriding the value beyond either extreme (0 or 99) will display "--" momentarily and the jump to the opposite
extreme. If the button is released while "--" is displayed, normal program control will resume and the display will again alternate.
ES00 No overrides.
ES01 VCC SOLENOID.
WARMER BUTTON: The VCC solenoid override is energized when the warmer button is depressed and the VCC will be engaged, ECC will display
99.
COOLER BUTTON: The solenoid is de-energized when the cooler button is depressed and VCC will not be engaged, ECC will display 00.
ES02 EGR SOLENOID.
WARMER BUTTON: The EGR solenoid override is energized when the warmer button is depressed and the EGR valve will receive a vacuum signal,
ECC will display 99.
COOLER BUTTON: The solenoid is de-energized when the cooler button is depressed and no vacuum signal to the EGR valve, ECC will display 00.
ES03 ISC MOTOR.
TEST CONDITIONS:
^
Vehicle must be in Park or Neutral.
^
A/C relay is OFF and EGR solenoid is de-energized. Spark advance is at an PCM/ECM calculated value, when test is active.
^
When ISC motor is stopped the ECC displays 50.
WARMER BUTTON:
(Engine off) The ISC plunger will extend until it ratchets once and the ECC will display 99.
(Engine on) "--" will be displayed.
COOLER BUTTON:
(Engine off) Retract ISC, FDC displays 00.
(Engine on) ISC will retract to base idle.
ES04 INJECTOR CUTOUT.
TEST CONDITIONS:
^
Vehicle must be in Park or Neutral.
^
A/C relay is OFF and ISC is fixed, and integrator and block learn are off, when test is active.
WARMER BUTTON: Depressing the warmer button will select an injector and will increment at the rate of one selection per second, and the ECC
will display injector selected.
COOLER BUTTON: Depressing the cooler button will cause injector cut-off and the ECC will display 00.
ES05 FUEL PUMP RELAY.
COOLER BUTTON:
Engine on, relay off, the ECC displays 00. the display will return to 99 when the button is released.
NOTE: Vehicle in Park or Neutral, (Engine On), the ECC will display 99, (Engine OFF), the ECC will display 00.
ES06 AIR SYSTEM.
WARMER BUTTON: Electric Switching Valve (ESV). Each time the warmer button is depressed the state of the valve will change. The right digit of
the ECC indicates the state of the ESV. 0 indicates the solenoid is de-energized. 1 indicates the solenoid is energized.
COOLER BUTTON: Electric Divert Valve (EDV) On/Off. Each time the cooler button is depressed the state of the valve will change. The left digit
indicates the state of the EDV. 0 indicates the solenoid is de-energized. 1 indicates the solenoid is energized.
INDICATOR STATUS:
1. 01 ESV on, EDV off: Air to air cleaner assembly.
2. 10 EDV on, ESV off: Air to catalytic converter.
