The instrument cluster indicators are illuminated by 1 of the following methods:
| • | The instrument cluster detects a concern with a discrete input. |
| • | A module sends a indicator illumination request message, via the class 2 serial data line |
Air Bag Indicator
The air bag indicator is a light emitting diode (LED) display that is located in the instrument cluster but is operated by a designated circuit from the inflatable restraint sensing & diagnostic module (SDM). A diagnostic trouble code (DTC) will be stored in the SDM for any related system malfunction.
Anti-Lock Indicator
The anti-lock indicator is a display that is located in the instrument cluster. The anti-lock indicator is operated by the electronic brake control module (EBCM). The anti-lock indicator will turn ON for 3 seconds when the ignition switch is placed in the RUN position. The anti-lock indicator will also turn ON when the instrument cluster receives class 2 information from the EBCM requesting the anti-lock indicator to be turned ON or if the cluster loses class 2 communication with the EBCM. A diagnostic trouble code (DTC) will be stored in the EBCM for any related system malfunction.
Brake Indicator
The brake warning indicator is a display that is located in the instrument cluster. The brake warning indicator is operated by the EBCM and the body control module (BCM). The brake warning indicator indicates a low fluid pressure condition exists in the brake system when the brake warning indicator finds ground through the pressure differential switch in the combination valve. The brake warning indicator also indicates the park brake is applied when the brake warning indicator finds ground through the park brake switch. When the park brake is set with the ignition switch is in the RUN position, the park brake indicator will flash. The BCM will command the indicator ON in order to indicate that the park brake is engaged. The EBCM will command the brake indicator ON in order to indicate a low fluid pressure condition.
Check Gauges Indicator
The check gauges indicator is a LED display located in the instrument cluster. The check gauges indicator turns ON for 3 seconds when the ignition switch is turned to the RUN position. The instrument cluster is constantly monitoring the engine coolant temperature and engine oil pressure when the engine s running. The engine coolant temperature information is sent to the instrument cluster over the Class 2 serial data line by the VCM/PCM. The engine oil pressure information is sent to the instrument cluster from a designated circuit connected to the oil pressure sensor. The instrument cluster will turn the CHECK GAUGES indicator ON if the engine coolant temperature gets too high or if the engine oil pressure gets too low while the engine is running.
CRUISE Indicator
The cruise indicator is a lamp that is located in the instrument cluster. When the cruise control has been engaged, the vehicle control module (VCM ) / powertrain control module (PCM) uses class 2 communication in order to send a message to the instrument cluster to turn ON the cruise indicator lamp.
High Beam Indicator
The high beam indicator is an incandescent lamp that is located in the instrument cluster. A class 2 serial data message from the BCM is sent to the instrument cluster when the high beams are turned ON. The BCM senses the input and sends the message to the instrument cluster to turn the indicator ON.
Left Turn Signal Indicator
The left turn signal indicator is an incandescent lamp that is located in the instrument cluster. The left turn signal indicator lamp has a designated circuit to the instrument cluster by the turn signal switch and the turn signal flasher.
Right Turn Signal Indicator
The right turn signal indicator is an incandescent lamp that is located in the instrument cluster. The right turn signal indicator lamp has a designated circuit to the instrument cluster by the turn signal switch and the turn signal flasher.
PRNDL Indicator (Park Reverse Neutral Drive Low)
The PRNDL display is a class 2 serial data message to the instrument cluster from the PCM/VCM. The PRNDL display is a vacuum florescent (VF) display which displays the fixed gear position of P, R, N, D, 3, 2, 1 surrounded by a moveable square flag in order to indicate the selected gear position. The position of the moveable square flag is sent to the instrument cluster from the transmission range switch over the class 2 serial data line. The transmission range switch and the neutral safety back up (NSBU) switch operate separately but are incorporated into one part. If the vehicle is equipped with a column shift steering column it will also have a park position switch. The park position switch (if equipped) must also be CLOSED in order for the instrument cluster to display the PARK position. Since the system is entirely electronic, there is not any internal adjustment. The PRNDL display will operate as follows:
| • | The PRNDL display will display the PARK position when a class 2 serial data message is received from the PCM/VCM indicating the transmission is in the PARK position and for vehicles which have a column shift on the steering column, the park position switch must also be CLOSED (low input). |
| • | The PRNDL display will display a gear position if a class 2 serial data message from the PCM/VCM is received indicating the gear position of the transmission. |
| • | The moveable square flag will not appear on the instrument cluster in order to show no gear was selected when the instrument cluster does not receive a class 2 serial data message from the PCM/VCM within 5 seconds of entering the UNLOCK or the RUN position. |
Refer to Engine Controls or Transmission/Transaxle for more information about the PRNDL indicator.
Park Switch (Column Shift Only)
The park position switch is only used on vehicles which have a gear shift lever on the column. The park position switch is part of the linear shift assembly in the steering column. The scan tool can display the state of the park switch.
OPEN is displayed when the gear shift lever is not in PARK.
CLOSED is displayed when the following conditions exist:
| • | The gear shift lever is in the PARK position |
| • | The gear shift lever is at the normal rest position |
| • | The park position switch is providing a ground to the instrument cluster for the park switch input |
Refer to Steering Wheel and Column for more information on the park switch.
Seat Belt Indicator
The seat belt indicator is a display that is located in the instrument cluster. The BCM uses class 2 serial data communication in order to command the seat belt indicator ON and OFF. This vehicle has an enhanced seat belt warning system. This system activates a warning lamp for about 75 seconds and an audible warning for about 8 seconds when the ignition switch is turned to the RUN position and the drivers sear belt is not buckled. The warning lamp will be constant for the first 20 seconds, then flash for the remaining 55 seconds. The audible warning only turns ON, and will stay ON when the drivers seat belt is not fastened during the 8 second time period. The warning lamp and the audible warning sequence of operation is as follows:
| • | Drivers Seat Belt Unbuckled - Turn the ignition switch to the RUN position. The warning lamp illuminates constantly for 20 seconds, then flashes for the remaining 55 seconds. The audible warning turns ON and stays ON for 8 seconds, then turns OFF. If the drivers seat belt buckle is buckled before the 8 seconds, the audible warning and lamp will turns OFF. |
| • | Drivers Seat Belt Buckled - Turn the ignition switch to the RUN position. The warning lamp will not illuminate and the audible warning stays OFF. If the drivers seat belt buckle is unbuckled prior to 8 seconds, the audible warning will tun ON for the balance of the 8 second delay. |
SERVICE ENGINE SOON (SES) Indicator
The service engine soon (SES) indicator is a display that is located in the instrument cluster but is operated by a designated circuit from the VCM/PCM. The SES should turn ON with the ignition switch in the RUN position and the engine OFF. The lamp should turn OFF 1-5 seconds after the engine starts. If the lamp stays ON or turns ON while driving, service to the emission control system may be required. Refer to
| • | Powertrain OBD System Check for 4.3L engines |
| • | Powertrain OBD System Check for 4.8L, 5.3L, and 6.0L engines |
TOW/HAUL Indicator (Automatic Transmission Only)
The TOW/HAUL indicator is located in the instrument cluster. When the TOW/HAUL button is depressed at the end of the shift lever, the BCM uses class 2 serial data communication in order to send a message to the instrument cluster to turn ON the TOW/HAUL indicator lamp.
Up-Shift Indicator (Manual Transmission Only)
The up-shift indicator is a display that is located in the instrument cluster. The up-shift indicator will turn ON when the instrument cluster receives class 2 serial data information from the VCM/PCM requesting the up-shift indicator to be turned ON. The up-shift indicator in the instrument cluster turns ON in order to indicate optimum shift points for maximum fuel economy. When this lamp turns ON, shift the transmission to the next higher gear range, if the conditions permit.
Control of the up-shift indicator is a function of the PCM/VCM. Several conditions are monitored, such as the engine speed, the load, and the throttle position in order to turn ON the lamp. If the lamp is erratic or inoperative, verify the integrity of the circuit. Then use the scan tool to command the up-shift lamp ON and OFF. If the scan tool can command the up-shift lamp ON and OFF, replace the PCM/VCM if no resolution if found.
4WD Indicator
The 4WD indicator is located in the instrument cluster. When the shift lever is placed in 4WD, the VCM/PCM uses class 2 serial data communication in order to send a message to the instrument cluster when to turn ON the 4WD indicator lamp.
Message Center
This cluster contains a message center module which can sequentially display up to 30 messages or ISO symbols. In the event that more than 1 message is required to be displayed at the same time in the message center, the messages will be sequentially displayed to the driver in 5 second intervals or 15 second intervals.
Message | Communication Type | Display Type | Message Color |
|---|---|---|---|
BATTERY FAULT | Class 2 from VCM/PCM | Continuous | Red |
SERVICE 4WD | Class 2 from ATC | Continuous | Amber |
CARGO DOOR AJAR | Class 2 from BCM | Continuous | Amber |
CARGO LAMP ON | Class 2 from BCM | Continuous | Amber |
CHANGE ENGINE OIL | Class 2 from VCM/PCM | Once an ignition cycle | Amber |
CHECK COOLANT TEMP | Class 2 from IPC/VCM/PCM | Continuous | Amber |
CHECK ENG OIL LEVEL | Class 2 from VCM/PCM | Continuous | Amber |
CHECK ENG OIL PRESSURE | Discrete wire | Continuous | Amber |
ENGINE OVER-HEATED | Class 2 from IPC/VCM/PCM | Continuous | Red |
LOW COOLANT | Class 2 from VCM/PCM | Continuous | Amber |
LOW FUEL | Class 2 from IPC/VCM/PCM | Continuous | Amber |
LOW WASHER FLUID | Discrete wire | Once an ignition cycle | Amber |
REDUCED ENGINE POWER | Class 2 from VCM/PCM | Continuous | Amber |
SECURITY | Class 2 from BCM | Continuous | Amber |
SERVICE 4WD | Class 2 from ATC | Continuous | Amber |
SERVICE RIDE CONTROL | Class 2 from RTD | Continuous | Amber |
TRANS FLUID HOT | Class 2 from IPC/VCM/PCM | Continuous | Amber |
TRANS HOT...IDLE ENGINE | Class 2 from IPC/VCM/PCM | Continuous | Red |
Communication Type
A message using the class 2 communication type is turned ON and OFF in the cluster by a class 2 serial data message from the applicable module (i.e. BCM, PCM/VCM).
A message using the discrete wire communication type is turned ON and OFF in the cluster by a wire from the applicable sensor (i.e. oil pressure/low washer switch).
Display Type
Once An Ignition Cycle
A message is sequenced into the message center display once per ignition cycle for 15 seconds.
Continuous
A message is sequenced into the message center display for 5 second intervals. If only one message is to be displayed in the message center, the message will not blink between these intervals so that the message appears to be displayed continuously. If another message is added to the display, the current message will time out and is inserted at the bottom of the display queue. The new message shall then be displayed for a 5 second interval.
Message Center Messages
Battery Charge Fault
The battery charge fault message is a class 2 serial data message from the PCM/VCM. The conditions for turning ON the battery message in the message center are described below.
| • | The battery charge fault message will be ON continuously when the ignition switch is turned to the RUN position (engine OFF). |
| • | The battery charge fault message will perform a 3 second bulb check immediately after the engine is started. |
CARGO DOOR AJAR
The CARGO DOOR AJAR message is sent to the cluster as a class 2 serial data message from the BCM. The CARGO DOOR AJAR message will be added to the message center display when the cargo door ajar switch is closed and removed from the message center when the cargo door ajar switch is open.
CARGO LAMP ON
The CARGO LAMP ON message is sent to the cluster as a class 2 serial data message from the BCM. The CARGO LAMP ON message will be added to the message center display when the cargo lamp switch is toggled ON and removed from the message center when the switch is toggled again.
CHECK COOLANT TEMP
The coolant temperature is sent to the cluster as a class 2 serial data value from the PCM/VCM. The cluster turns ON the CHECK COOLANT TEMP message based on the coolant temperature. If the coolant temperature is greater than 121°C (250°F) it will be added to the message center and removed when the coolant temperature drops below 118°C (245°F).
CHANGE ENGINE OIL
The CHANGE ENGINE OIL message is sent to the cluster as a class 2 serial data message from the VCM/PCM. This message will appear in order to inform the operator that the maintenance interval has been reached for the engine oil and filter. The maintenance interval is usually between 3,000-7,500 miles and/or 3-12 months, whichever comes first. Under severe conditions, the indicator may come ON sooner than 3,000 miles or 3 months. In order to reset the CHANGE ENGINE OIL message, turn the ignition switch to RUN position and the engine OFF. Fully press and release the accelerator pedal three times within 5 seconds. The CHANGE ENGINE OIL message will flash for 5 seconds in order to notify the driver that the system has been reset. Exactly when the indicator comes ON is based on a complex formula that takes into account some of the following vehicle inputs:
| • | Coolant Temperature |
| • | Engine Speed |
| • | Vehicle Speed |
| • | Oil Temperature Estimated |
| • | Power Up Manifold Temperature |
| • | Power Up Coolant Temperature |
| • | Engine running |
| • | Actual Engine Torque |
| • | Vehicle Speed |
| • | Odometer |
CHECK ENG OIL LEVEL
The CHECK ENG OIL LEVEL message is sent to the cluster as a class 2 serial data message from the VCM/PCM. The CHECK ENG OIL LEVEL message will be added to the message center display when the VCM/PCM receives the engine oil level low input from the engine oil level switch.
CHECK ENG OIL PRESSURE
The CHECK ENG OIL PRESSURE input to the instrument cluster is a discrete wire from the oil pressure sensor. The oil pressure sensor output signal is a variable resistance to ground, as measured by the instrument cluster. The conditions for asserting the CHECK ENG OIL PRESSURE message in the message center display are described below.
| • | The CHECK ENG OIL PRESSURE message will be added to the display when the input resistance is less than 5 ohms and the engine has been running for more than 5 seconds. |
| • | The CHECK ENG OIL PRESSURE message will be removed from the display if the input resistance increases to 12 ohms. |
ENGINE OVERHEATED
The coolant temperature is sent to the cluster as a class 2 serial data value from the PCM/VCM. The cluster turns ON the ENGINE OVERHEATED message based on the coolant temperature. If the coolant temperature is greater than 128°C (262°F) the message will be added to the message center and removed when the coolant temperature drops below 125°C (257°F).
LOW COOLANT
The LOW COOLANT message is sent to the cluster as a class 2 serial data message from the VCM/PCM. The LOW COOLANT message will be added to the message center display when the VCM/PCM receives the coolant level low input from the engine coolant level switch in the fill tank.
LOW FUEL
The LOW FUEL message is a class 2 serial data message from the PCM/VCM to the instrument cluster based on the fuel level (percent of fuel). The conditions for adding the LOW FUEL message to the message center are described below.
| • | The LOW FUEL message will be added to the message center display if the instrument cluster receives fuel level is less than, or equal to, 18 percent fuel. |
| • | The LOW FUEL message wiil be removed from the message center display if the instrument cluster receives fuel level greater than, or equal to, 22 percent fuel. |
LOW WASHER FLUID
The LOW WASHER FLUID message input to the cluster is a discrete wire from the washer bottle switch. The LOW WASHER FLUID message shall be displayed when the circuit to the cluster is grounded by the washer bottle switch continuously for 30 seconds. The LOW WASHER message will be displayed continuously for 15 seconds and only once per ignition cycle, and then removed from the message center display.
REDUCED ENGINE POWER
The REDUCED ENGINE POWER message is sent to the cluster as a class 2 serial data message from the VCM/PCM. The REDUCED ENGINE POWER message will be added to the message center display when the engine is over-heated.
SECURITY
The SECURITY message is a class 2 serial data message from the BCM. The SECURITY message can be commanded ON by both the Passlock and the content theft deterrent (CTD) systems. The SECURITY message can be ON continuously, or flashing.
SERVICE 4WD
The SERVICE 4WD message is sent to the cluster as a class 2 serial data message from the automatic transfer case (ATC) module. The SERVICE 4WD message will be added to the message center display any time a diagnostic trouble code is set.
SERVICE RIDE CONTROL
The SERVICE RIDE CONTROL message is sent to the cluster as a class 2 serial data message from the real time damping (RTD) module. The SERVICE RIDE CONTROL message will be added to the message center display any time a diagnostic trouble code is set.
TRANS FLUID HOT
The trans temperature is sent to the cluster as a class 2 serial data value from the PCM/VCM. The cluster turns ON the TRANS FLUID HOT message based on the trans temperature. If the trans temperature is greater than 130°C (266°F) it will be added to the message center and removed when the trans temperature drops below 127°C (260°F).
TRANS HOT...IDLE ENGINE
The transmission temperature is sent to the cluster as a class 2 serial data value from the PCM/VCM. The cluster turns ON the TRANS HOT...IDLE ENGINE message based on the transmission fluid temperature. If the transmission temperature is greater than 135°C (275°F) it will be added to the message center and removed when the transmission temperature drops below 132°C (270°F).
