Displays Test
Certain instrument panel cluster (IPC) features are tested when the   ignition is turned on in order to verify the features are working properly.     The following indicators illuminate for 3 seconds:
|     •  | The CHECK GAGES indicator | 
 
|     •  | The GATE AJAR indicator | 
 
|     •  | The Park Brake indicator | 
 
|     •  | The SERVICE 4WD indicator | 
 
|     •  | The TOW / HAUL indicator | 
 
|     •  | All gages sweep to their minimum physical position and then to   their actual physical position. | 
 
 The following indicators illuminate for the specified  times:
|     •  | The AIR BAG indicator flashes 7 times. | 
 
|     •  | The Fasten Safety Belt indicator illuminates for 20 seconds   followed by 55 seconds of flashing with the drivers seatbelt unfastened,    or,  the Fasten Safety Belt indicator will illuminate for 8 seconds    with the drivers seatbelt fastened. | 
 
|     •  | The SERVICE ENGINE SOON (MIL) indicator illuminates and remains   on. | 
 
Indicators and Warning Messages
Refer to 
Indicator/Warning Message Description and Operation 
.
Engine Coolant Temperature Gage
The IPC displays the engine coolant temperature as determined by the   PCM. The IPC receives a class 2 message from the PCM indicating the    engine coolant temperature. The engine coolant temperature gage defaults   to  100°F (40°C) or below if:
|     •  | The PCM detects a malfunction in the engine coolant temperature   sensor circuit. | 
 
|     •  | The IPC detects a loss of class 2 communications with the   PCM. | 
 
Engine Oil Pressure Gage
The IPC uses the engine oil pressure sensor signal to determine the   engine oil pressure. The oil pressure sensor signal circuit is solely dedicated    to the IPC.   The engine oil pressure sensor signal to the IPC is a variable    resistance ranging from 0-90 ohms.  A sensor resistance of   1 ohms   will  display as 0 psi (0 kPa) and a resistance   of 88 ohms   will display as 80 psi (550 kPa).
Fuel Gage
The IPC displays the fuel level as determined by the PCM. The IPC receives   a class 2 message from the PCM indicating the fuel level percent.  The   fuel gage defaults to empty if:
|     •  | The PCM detects a malfunction in the fuel level sensor circuit. | 
 
|     •  | The IPC detects a loss of class 2 communications with the   PCM. | 
 
When the fuel level is less than a pre-determined value, the low fuel   indicator illuminates.
Odometer
The IPC contains a season odometer and a trip odometer. Momentarily   press the  trip/reset switch on the IPC in order to toggle between the season    odometer  and the trip odometer. Press the trip/reset switch for greater   than  2 seconds, while the trip odometer is displayed, in order to    reset  the trip odometer.
 The IPC displays the vehicle mileage and trip  mileage   as  determined   by  the IPC. The IPC calculates the mileage based  on the vehicle speed signal     circuit from the PCM. The odometer will display  'error' if  an internal     IPC memory failure is detected.
PRNDL Display
The IPC displays the selected gear position as determined by the PCM.   The IPC receives a class 2 message from the PCM indicating the gear            position. The PRNDL displays blank if:
|     •  | The PCM detects a malfunction in the transmission range switch   circuit. | 
 
|     •  | The IPC receives a class 2 message indicating the park   position and the column park switch indicates a position other than park such as an open   input. | 
 
|     •  | The IPC detects a loss of class 2 communications with the   PCM. | 
 
Speedometer                  
The IPC displays the vehicle speed based on the information from the   PCM. The PCM converts the data from the vehicle speed sensor to a 4000 pulses/mile    signal. The IPC uses the vehicle speed signal circuit from the PCM in order    to calculate the vehicle speed.  The  speedometer  defaults  to 0 km/h    (0 mph) if  a malfunction  in the  vehicle     speed    signal  circuit    exists.
Tachometer
The IPC displays the engine speed based on the information from the   PCM. The PCM converts the data from the engine speed sensor  to a 2 pulses/engine    revolution signal. The IPC uses the engine speed signal circuit from the   PCM  in order to calculate the engine speed.  The tachometer defaults to  0 rpm   if a malfunction  in the engine speed  signal circuit exists. 
Voltmeter
The IPC displays the system voltage as detected at the ignition 1   voltage input of the IPC. When the engine is ON, the gage should be between    10 and 16 volts.