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Override

BCM OVERRIDE DISPLAYS:

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 ECC panel. If the selected override is not allowed under the current conditions a " =- =- " display will result.

Touching the "WARM" or "COOL" buttons on the ECC panel begins the override. The "WARM" button will increase the value while the "COOL" button will decrease it. 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 in override test, touching the "OFF" button will allow selection of another test type, however, the ECC panel will continue to display the selected override. By selecting another test type and test, and then touching the "WARM" or "COOL" buttons, 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 the heating and air conditioning 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 "WARM" and "COOL" buttons on the ECC panel. Touching the "WARM" button 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 "COOL" button will force the program number to decrease until the value of "O" 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 "O" to "99" and simultaneously observe the reaction of any of the BCM data parameters.

BS02 VACUUM FLUORESCENT (VF) DIMMING - The automatic control of dimming can be bypassed by a manual override feature using the override control pads. "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" The automatic control of dimming can be bypassed by a manual override feature using the override control pads. "99" represents the max brightness and "0" represents the max dimming (outside lights do not have to be "ON" to override incandescent dimming). This allows the technician to control the dimming.

BS05 "C/C SERVO" The cruise control 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 override control pads on the ECCP. "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 (BD70). 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 once.

BS06 "OPTION CONTENT #1" The option content #1 override allows the ability to change the contents of which options the vehicles BCM thinks it has, (stored in EEPROM). The OPTION CONTENT is displayed (in the trip odometer) as a number from 0 to 255. Each number is a code which represents option content. The BCM uses this value to determine how to operate the displays and electronic controls. Incorrect option values may cause many different problems. To determine the proper OPTION 1 value, use the table below:

If vehicle is equipped with: ADD

U.S. car (all except Canadian and export cars) 128
Export displays (option code NM8) 32
Reatta body style 16
Twilight sentinel 2

The display will show what option number is currently in the vehicle upon entry. To change the option content number press the Warmer or Cooler switches until the correct number, corresponding to vehicle equipped options, appears. When the correct number appears in the odometer, press and hold the "HEATER" and "DEFROST" switches simultaneously for 3.0 seconds. This will permanently change the EEPROM program to the number (options) in the odometer.

BS07 The "OPTION CONTENT 2" The option content #2 override allows the ability to change the contents of which options the vehicles BCM thinks it has, (stored in EEPROM). The OPTION CONTENT is displayed (in the trip odometer) as a number from, 0 to 255. Each number is a code which represents option content. The BCM uses this value to determine how to operate the displays and electronic controls. Incorrect option values may cause many different problems. To determine the proper OPTION 2 value, use the table below:

If vehicle is equipped with: ADD

Washer fluid level sensor (All cars) 128
Universal theft deterrent* (option code UA6 64
Anti-lock brakes (option code JL9) 32
Oil level sensor (All cars) 4

*NOTE: Universal theft deterrent listed in the table above is not the passkey theft deterrent system standard on all 1990 Riviera/Reattas.

The display will show what option number is currently in the vehicle upon entry. To change the option content number press the Warmer or Cooler switches until the correct number, corresponding to vehicle equipped options, appears. When the correct number appears in the odometer, press and hold the "HEATER" and "DEFROST" switches simultaneously for 3.0 seconds. This will permanently change the EEPROM program to the number (options) in the odometer.
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