Riviera V6-231 3.8L VIN C SFI (1989)
Body Control Module: Reading and Clearing Diagnostic Trouble Codes
Data Parameters
BCM DATA DISPLAYS:
While in this mode, the display will show eighteen data messages and the data value of each. This information will assist in tracking down emission or
driveability problems, since the displays can be viewed while the vehicle is being driven.
Data displays are operated as follows:
1.
Pressing the "OFF" button will stop the test selection process and return the display to the next available test type for the selected system.
2.
Pressing the "LO" fan button will display the next smaller test number for the selected test type. If this button is touched with the lowest test
number displayed, the highest test number will then appear.
3.
Pressing the "HI" fan button will display the next larger test number for the selected test type. If this pad is touched with the highest test number
displayed, the lowest test number will then appear.
BD20
The commanded blower voltage "BLWR VOLTS" is displayed in volts from 0 to system voltage.
BD21
The Engine Coolant Temperature "COOLANT TP" is displayed in degrees (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 valve (door) "COM MIX DR" 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 valve (door) "ACT MIX DR" 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 MODE" is displayed as a number from 0 to 11. Each number is a code which represents the following air delivery modes:
0 = Auto - Recirculate Upper
1 = Auto - Outside Upper
2 = Auto - Bi-Level
3 = Auto - Heater-Defog
4 = Auto - Lower
5 = OFF
6 = Normal Purge
7 = Cold (DEF) Purge
8 = Defog
9 = Forced Lower
10 = Forced Upper
11 = Forced Bi-Level
BD25
The in-car temperature "IN CAR TP" is displayed in degrees (°C), from -40° to 102°.
BD26
The actual outside temperature "OUTSIDE TP" is displayed in degrees (°C), from -40° to 93°. This valve 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 "HI SIDE TP" (condenser output) is displayed in degrees (°C) from -40° to 215°.
BD28
The low side temperature "LO SIDE TP" (evaporator input) is displayed in degrees (°C) from -40° to 93°.
BD32
The sunload temperature sensor "SUN TP" is displayed in degrees (°C) from 40 to 102.
BD40
The actual "FUEL LEVEL" is displayed in gallons from 0 to 17.0. This value represents actual sensor position and is not restricted by the
features used to eliminate fuel slosh effects on the customer display value. The 0 and 17.0 represent the lower and upper limits of travel of the
tank sensor. Some fuel is available above and below the sensor stops but is not measurable and varies.
BD41
The "PRND321" is displayed in a 4 digit binary number.
P
0110
R
0011
N
1010
0D 1001
D
0000
