Instrument Cluster

ELECTRO/MECHANICAL INSTRUMENT CLUSTER (EMIC)
There are 4 (four) different types of 2002 PL Instrument Clusters.
- Base
- Premium
- Luxury
- AutoStick

The Premium cluster is a Base cluster that is equipped with a tachometer and a low fuel indicator.

The Luxury cluster has the same features as the Premium with an additional black overlay and chrome rings.

The AutoStick cluster is the Luxury cluster with the AutoStick function.

The overlays for Premium, Luxury, and AutoStick clusters have the same indicator layout.

The Transmission Control Module (TCM) controls the Vacuum Fluorescent (VF) PRND or Auto-Stick display. The cluster will illuminate the appropriate PRND or gear position based on PCI Bus data received from the TCM.

The Instrument Cluster Speedometer, Tachometer, and Engine Coolant Temperature gauges are positioned using Programmable Communication Interface (PCI) bus messages received from the Powertrain Control Module (PCM). The fuel level information is calculated by the cluster based on a hard wire input from the fuel level sensor in the fuel pump module.

Indicators
The Cluster also contains warning indicators that are illuminated by hard wired inputs or by messages received from other modules on the PCI Bus.

The instrument cluster has indicators for the following systems:
- Front Fog Lamp
- Rear Fog Lamp (if so equipped)
- Traction Control OFF (if so equipped)
- Brake
- ABS (if so equipped)
- Cruise (if so equipped)
- Door
- Traction Control Active (if so equipped)
- Left Turn Signal
- Right Turn Signal
- High Beam
- Malfunction Indicator Lamp (MIL)
- Low Oil Pressure
- Low Fuel Indicator
- Seatbelt
- Battery
- Airbag
- Security (if so equipped)

The Odometer/Trip Meter is a Vacuum Fluorescent Display (VFD) that is controlled by PCI Bus messages received from the PCM. It is composed of six, 7-segment displays and a decimal point. The display may show the odometer mileage, the trip odometer mileage, P-codes, "no buS" for loss of bus communication with other modules on the bus, and "FUSE" for loss of battery fuse. The VFD also displays the "Door", "Cruise", and "Trac" messages.

PRND/Autostick (if so equipped) - The PRND/Autostick display is controlled by the Transmission Control Module (TCM). The cluster will illuminate the appropriate PRND/gear based upon the message received by the TCM.

The instrument cluster warning/indicator lamps are all serviceable Light Emitting Diodes (LED's). The instrument cluster must first be removed, and then the defective LED just turns out with needle nose pliers.

All gauges in the electronic clusters are the analog type gauges. When the ignition switch is moved to the OFF position, the cluster drives each gauge to its lowest position. The individual gauges are not serviceable and require complete replacement of the cluster if one or more gauges are inoperable.

One button is used to switch the display from trip to total mileage. Holding the button when the display is in the trip mode will reset the trip mileage. This button is also used to put the cluster in self-diagnostic mode. Refer to Electrical, Instrument Cluster, Standard Procedures-Cluster Self-Diagnostics. Most of the indicators will come on briefly for a bulb heck when the ignition is turned from OFF to ON. All of the LED's are replaceable.

The cluster calculates the appropriate odometer mileage based on PCI bus information received from the PCM. The VF display also displays the "Door" "Trac", and "Cruise" messages. If the instrument cluster experiences a loss of communication with the PCI bus, the cluster will display "no buS" in the display If the cluster determines that there is not 8.0 volts at the battery input, then the cluster shall alternately display "FUSE" and the odometer mileage.
- Front Fog Lamp (if so equipped) - Hard wire input - Cluster will illuminate the indicator when the front fog lamp input is at Vehicle System Voltage (VSV).
- Rear Fog Lamp (if so equipped) - Hard wire input - Cluster will illuminate the indicator when the rear fog lamp input is at VSV
- Traction Control OFF (if so equipped) - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate bus message from the ABS module.
- Brake - Hard wire OR PCI bus driven - Cluster will illuminate the indicator if the park brake switch is grounded OR after receiving the appropriate message from the ABS module.
- ABS (if so equipped) - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate message from the ABS module.
- Cruise (if so equipped) - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate message from the PCM.
- Door - Hard wire input - Cluster will illuminate the indicator if either door input is grounded for more than 250 milliseconds.
- Traction Control Active (if so equipped) - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate message from the ABS module.
- Left Turn Signal - Hard wire input - Cluster will illuminate the indicator if the left turn signal input is at VSV
- Right Turn Signal - Hard wire input - Cluster will illuminate the indicator if the right turn signal input is at VSV
- High Beam - Hard wire input - Cluster will illuminate the indicator whenever the high beam switch input is at VSV
- Malfunction Indicator Lamp (MIL) - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate message from the PCM.
- Low Oil Pressure - PCI bus driven - Cluster will illuminate the indicator after receiving the appropriate message from the PCM.
- Low Fuel Indicator - Cluster will illuminate based upon fuel level calculated by the cluster (using data received from the hard wire input from the fuel level sensor).
- Seatbelt - Hard wire - Cluster will illuminate whenever the seatbelt input is grounded with the ignition in RUN mode.
- Battery - PCI bus driven - Cluster will illuminate after receiving the appropriate message from the PCM.
- Airbag - PCI bus driven - Cluster will illuminate after receiving the appropriate message from the airbag control module.
- Security (if so equipped) - PCI bus driven - Cluster will illuminate whenever the remote keyless entry (RKE) input is grounded and the cluster has a battery feed. Cluster will flash the indicator based upon the message received from the sentry key immobilizer module (SKIM).

Illumination Lamps
The illumination lamps are hard wired in the Instrument Cluster. When the Park or Headlamps are turned ON, the cluster receives a hard wire input from the Multi-Function Switch. The cluster sends a Panel Lamps Dimmer Signal to ground through the Multi-Function Switch. The varying voltage drop is sensed by the Instrument Panel Drivers to create a corresponding amount of illumination dimming. This dimming level is then sent out from the cluster to other components.

The high beam indicator, turn signals, and illumination bulbs are serviceable. The instrument cluster must first be removed, and then the defective bulb and socket turns out. The bulb locations are printed on the back cover of the instrument cluster.

The cluster will communicate with the DRB III to display PCI Engine Info, PCI Bus info, and certain inputs/outputs. The Cluster is also capable of performing a diagnostic self-test that is actuated by depressing and holding the Odometer trip reset stalk while cycling the ignition from the off to the on position. The Cluster will position all of the gauges at specified calibration points and will illuminate all the PCI Bus controlled indicators. The Cluster will also illuminate each segment of the VF display.

The instrument cluster controls the courtesy lamps. It receives and sends messages to other modules via the PCI bus circuit. It controls all the instrument illumination and the chime is also an integral part of the cluster. The front turn signals are wired through the cluster and then go to the front lamps. The reason being that the DRL module is built into the cluster (if equipped).

If the Cluster does not detect voltage on the Courtesy Lamp circuit, the message "FUSE" will alternate with the odometer/trip odometer for 30 (thirty) seconds after the ignition is turned ON and for 15 (fifteen) seconds after the vehicle is first moved.

ABS INDICATOR
The amber ABS warning indicator lamp is located in the instrument cluster.

When the ignition key is turned to the ON position, the amber ABS warning indicator lamp is lit until the Controller Anti-Lock Brake (CAB) completes its self-tests and turns OFF the lamp (approximately 4 seconds). The amber ABS warning indicator lamp will illuminate when the CAB detects a condition that results in the shutdown of ABS function. The CAB sends a message to the mechanical instrument cluster (MIC) instructing it to turn ON the amber ABS warning indicator lamp.

Under most conditions, when the amber ABS warning indicator lamp is ON, only the ABS function of the brake system is affected; The electronic brake distribution (EBD), the base brake system and the ability to stop the vehicle are not affected.

MALFUNCTION INDICATOR LAMP MIL
Refer to the Instrument Cluster for more information.

The PCM supplies the malfunction indicator (check engine) lamp ON/OFF signal to the instrument panel through the PCI Bus. The PCI Bus is a communications port. Various modules use the PCI Bus to exchange information.

The Check Engine lamp comes ON each time the ignition key is turned ON and stays on for 3 seconds as a bulb test.

The Malfunction Indicator Lamp (MIL) stays ON continuously when the PCM has entered a Limp-In mode or identified a failed emission component. During Limp-in Mode, the PCM attempts to keep the system operational. The MIL signals the need for immediate service. In limp-in mode, the PCM compensates for the failure of certain components that send incorrect signals. The PCM substitutes for the incorrect signals with inputs from other sensors.

If the PCM detects active engine misfire severe enough to cause catalyst damage, it flashes the MIL. At the same time the PCM also sets a Diagnostic Trouble Code (DTC).

For signals that can trigger the MIL (Check Engine Lamp) refer to the On-Board Diagnostics.

RED BRAKE WARNING INDICATOR
The red BRAKE warning indicator lamp is located in the instrument panel cluster and illuminates when a low brake fluid condition occurs or when the parking brake lever is applied with the ignition key in the ON position. In addition, the red BRAKE warning indicator lamp illuminates when the ignition switch is moved from the OFF to the ON or CRANK position. This is done to check the LED's operation.

Problems with this system will generally be of the type where the warning indicator lamp fails to turn ON when it should, or remains ON when it should not.

The red BRAKE warning indicator lamp LED is supplied with current anytime the ignition switch is ON. The bulb is illuminated by completing the ground circuit using any of the following components:
- The brake fluid level switch located in the master cylinder reservoir
- The parking brake switch mounted on the parking brake lever
- The ignition switch when the ignition switch is first moved to the ON or CRANK position
- The mechanical instrument cluster (MIC) (with ABS)
- The ABS electronic brake distribution (EBD)

As the fluid drops below the minimum level, the brake fluid level switch in the brake fluid reservoir closes and grounds the red BRAKE warning indicator lamp circuit. This turns on the red BRAKE warning indicator lamp. At this time, the master cylinder fluid reservoir must be checked and filled to the full mark with DOT 3 brake fluid. An abnormal loss of brake fluid in the master cylinder fluid reservoir could be caused by a leak in the hydraulic system. The entire brake hydraulic system should be checked for evidence of a leak.

The red BRAKE warning indicator lamp can be turned ON by the MIC in the case where the ABS is experiencing a problem where the amber ABS warning indicator lamp needs to be illuminated and cannot. The MIC will then illuminate the red BRAKE warning indicator lamp.