Power, Ground, and Class 2
The IPC receives battery positive voltage from the rear fuse block IP
fuse circuit. The IPC receives ignition voltage from the rear fuse block
IGN 1 fuse circuit. The IPC has 2 ground inputs that come from
two separate vehicle ground circuits.
The IPC receives all class 2 serial data messages, via the class 2
serial data line.
The dash integration module (DIM) is responsible for determining the
power mode for the electrical system. The IPC does not sense ignition voltage
unless there is a loss of communication with the DIM. The DIM broadcasts
the power via class 2 serial data message. The power modes are the
following:
| • | OFF - Asleep -- The IPC disables all displays except for
the theft LED. |
| • | OFF - Awake -- The Theft LED, Security, and High Beam indicators
are available to be activated if conditions are correct. The IPC disables
all other displays. |
| • | UNLOCK -- The PRNDL display, Theft LED, Security, High Beam,
and BRAKE indicators are available to be activated if conditions are correct.
The IPC disables all other displays. |
| • | RAP-UNLOCK -- The PRNDL display, Theft LED, Security, High
Beam, and BRAKE indicators are available to be activated if conditions are
correct. The IPC disables all other displays. |
| • | Accessory (ACC) -- The PRNDL display, Theft LED, Security,
High Beam, and BRAKE indicators are available to be activated if conditions
are correct. The IPC disables all other displays. |
| • | RUN -- All gauges, indicators, and displays are available
to be activated if conditions are correct. |
| • | CRANK -- The IPC disables all displays. |
| • | Retained Accessory Power (RAP) -- The PRNDL display, Theft
LED, Security, and High Beam indicators are available to be activated if conditions
are correct. The IPC disables all other displays. |
| • | Power-up Moding -- Upon transition to power mode (RUN), all
displays will appear to be powered up simultaneously. During power up the
cluster is sent class 2 information with which it configures its displays.
If the cluster does not receive the class 2 information it is looking
for, within a predetermined amount of time, the cluster will request the information
a second time. If the cluster does not receive the message, the cluster will
determine that the message has failed and default its display. When the cluster
transitions to the RUN power mode, the cluster will cycle through the following
events: |
| • | The auxiliary gauges will WOW beginning 1 second after
the cluster transitions to the RUN power mode. |
| • | The pointers on the speedometer and tachometer will go from the
minimum to the maximum scale in 1.5 seconds. |
| • | The odometers and the car outline with the doors and trunk segments
will perform a full segment check. |
| • | The compass display will cycle from N to E to S to W at 750 ms
intervals. |
| • | The DIC display will not perform a segment check. |
| • | All indicators will perform a bulb check. |
| • | The traction switch LED will be enabled, if present. |
| • | Power-down moding -- The cluster will power down the displays
when the battery voltage drops below 9 volts (not caused by a temporary
disturbance). The English/Metric status of the cluster is stored in KAM. The
cluster will also power down upon transition to the OFF-ASLEEP power mode.
When the cluster is powered down two functions may be operable, the Theft
LED and the odometer. |
| • | Loss of Power Mode due to DIM Failure -- If the power mode
is unknown due to a loss of communication with the DIM, the instrument cluster
will enter power mode RUN when the ignition voltage circuit is active. If
the ignition voltage circuit is inactive, the instrument cluster will enter
power mode OFF - Awake. |
Instrument Cluster Inputs
The instrument cluster receives direct inputs for the operation of various
gauges, indicators, and displays. The signals are the following:
| • | Malfunction indicator lamp (MIL) |
| • | Brake fluid level signal |
| • | Windshield washer fluid level signal |
| • | Traction control switch LED control |
DIC Switches
The DIC switches are wired directly to instrument cluster. Each switch
is normally open. Activating the switch closes the contacts completing a ground
circuit and supplying a signal to the instrument cluster. The IPC will take
appropriate actions when a DIC switch is pressed.
If any switch is active for 15 seconds, the IPC will ignore the
signal and consider the input to be inactive until the switch signal is detected
to be inactive. An ignored switch will not have effect on the operation of
the other DIC switches.
