ABS Warning Indicator
The electronic brake control module (EBCM) controls the ABS warning indicator. The EBCM turns ON the indicator for approximately 3 seconds in order to perform a bulb test during engine start-up. The EBCM flashes the ABS warning indicator in order to warn the driver that an ABS malfunction exists. The malfunction may have degraded base brake performance. A solid (not flashing) ABS warning indicator warns the driver that a problem has been detected that affects the operation of ABS. This does not affect normal brake performance.
For more information of ABS, refer to Antilock Brakes.
Air Bag Warning Indicator
The air bag warning indicator is controlled by the Inflatable Restraint Diagnostic Energy Reserve Module with Sensor (SDM). The SDM turns ON the indicator for approximately 3 seconds in order to perform a bulb test during engine start-up. The SDM turns ON the indicator in order to warn the driver of an electrical malfunction within the supplemental inflatable restraint (SIR) system. This malfunction may affect the operation of the SIR system.
For more information on SIR, refer to Supplemental Inflatable Restraint (SIR) System.
BRAKE Warning Indicator
The BRAKE warning indicator lights under the following conditions:
| • | A low brake fluid level in the master cylinder is detected. |
| • | The parking brake switch is closed. |
| • | Certain ABS diagnostic trouble codes (DTC) are set, while under the control of the EBCM. |
This indicator warns the driver that a base brake problem may exist.
For more information on ABS, refer to Antilock Brake System.
Charge Warning Indicator
The powertrain control module (PCM) controls the charge warning indicator. The instrument cluster turns ON the indicator during engine start-up for a bulb test. The PCM turns ON the indicator whenever the PCM detects one of the following conditions:
| • | An undervoltage (11.2 volts) |
| • | An overvoltage (16.5 volts) |
Coolant Warning Indicator
The coolant warning indicator control monitors the engine coolant temperature signal from the engine coolant temperature sensor. The indicator control will turn ON the coolant warning indicator under the following conditions:
| • | At an engine coolant temperature of approximately 124°C (255°F) |
| • | At a sender resistance of approximately 53 ohms |
For more information, refer to Engine Controls.
Door Ajar Indicator
The door ajar indicator is OFF whenever all of the following doors are closed:
| • | The right front door |
| • | The left front door |
| • | Both sliding doors, if equipped |
| • | The liftgate |
When any one of these door mechanisms is not fully secured, the affected door ajar indicator switch will close. This allows current to flow through CKT 804 to ground, and light the DOOR AJAR indicator.
Instrument Cluster
Engine Coolant Temperature Gage
The engine coolant temperature gage is operated by 2 coils. Battery voltage is applied to both coils. One voltage is grounded directly. The other voltage is grounded through the engine coolant temperature sender. The engine coolant temperature sender has 44 ohms resistance at 125°C (260°F). The sender resistance increases at lower temperatures. Resistance is approximately 1365 ohms at 37°C (100°F). This causes the current flow to increase through the following components as the coolant temperature decreases, and moves the pointer:
| • | The coolant temperature sender |
| • | One coil |
Fasten Belts Indicator
The seat belt/ignition key/lamps alarm controls the fasten belts indicator. When the ignition switch is first turned to the RUN position with the engine off, the alarm will sound until one of the following conditions are met:
| • | 4-8 seconds elapses. |
| • | The seat belt is fastened. |
The indicator will turn ON until the seat belt is fastened.
For more information, refer to Audible Warnings in Electrical Diagnosis.
Fuel Gage
The pointer of the fuel gage is moved by the magnetic fields of 2 coils. The coils are at right angles to each other. Battery voltage is applied to the E coil. The circuit divides at the opposite end of this coil. One path continues to ground through the F coil. Another path continues to ground through the variable register of the fuel level sender.
| • | When the tank is low, the resistance of the fuel level sender is low. A large flow of current passes through the E coil and the fuel level sender resistor. This pulls the pointer towards E on the scale. |
| • | When the tank is full, the fuel level sender resistance is high. More current now flows through the F coil. This pulls the pointer to F on the scale. |
With 2 coils operating the pointer, the fuel gage is not affected by changes in the voltage of the system.
High Beam Indicator
Power is supplied to circuit 11 when the following conditions are met:
| • | The headlamps are ON. |
| • | The headlamp dimmer switch is in the HIGH position. |
This powers the following items:
| • | The high beam headlamps |
| • | The high beam indicator in the instrument cluster |
For more information, refer to Headlights in Electrical Diagnosis.
LOW COOLANT Indicator
The LOW COOLANT indicator receives battery voltage with the ignition switch in the following positions:
| • | RUN |
| • | BULB TEST |
| • | START |
The instrument cluster turns ON the indicator for approximately 1 second during engine start-up in order to perform a bulb check. The engine coolant level switch grounds the indicator when the fluid in the coolant reservoir falls below minimum recommended level.
LOW FUEL Indicator
When the powertrain control module (PCM) receives a signal from the fuel sending unit that approximately 1/8 tank of fuel remains, the PCM sends a ground signal to the LOW FUEL indicator in the instrument cluster. This signal turns ON the indicator.
LOW OIL LEVEL Indicator
The powertrain control module (PCM) controls the LOW OIL LEVEL indicator. The PCM samples the oil level once per ignition cycle. This sampling occurs at power-up, provided that the oil has had sufficient time to drain into the oil pan from the last power-down.
| • | If the engine coolant temperature is greater than 75°C (167°F), 3 minutes must elapse after power-down for the PCM in order to sample the oil level. |
| • | If the engine coolant temperature is less than 75°C (167°F), the PCM tests for a decline of at least 11°C (20°F) before sampling the oil. |
LOW TRACTION Indicator
The electronic brake control module (EBCM) controls the LOW TRACTION indicator. The EBCM lights the LOW TRACTION indicator for the following reasons:
| • | In order to alert the driver of a low traction situation |
| • | In order to inform the drive that the TCS is operating |
The LOW TRACTION indicator remains ON for approximately 3-4 seconds after the TCS event is completed.
For more information, refer to Warning Indicators in Antilock Brake System.
Oil Pressure Warning Indicator
The oil pressure warning indicator receives battery voltage with the ignition switch in the following positions:
| • | RUN |
| • | BULB TEST |
| • | START |
The instrument cluster turns the indicator ON during engine start-up in order to perform a bulb check. The indicator is grounded by the engine oil pressure indicator switch with a low oil pressure condition.
SERVICE ENGINE SOON Indicator
The powertrain control module (PCM) controls the SERVICE ENGINE SOON indicator. For more information, refer to Engine Controls.
Speedometer and Odometer
The vehicle speed sensor (VSS) is a gear-driven permanent magnet generator. The VSS is housed in the vehicle's transaxle. This sensor generates a sine wave output with a frequency proportional to the vehicle speed. The powertrain control module (PCM) converts this signal to an output that is switched to ground at a frequency of 4000 pulses per mile. This signal (CKT 389) drives the speedometer and the odometer. Various other components also use this signal.
Tachometer
The tachometer displays engine speed in RPM. Voltage pulses are taken from the powertrain control module (PCM). The pulses are sent to the tachometer. The tachometer responds to the frequency of the voltage pulses. This frequency increases with engine speed. Solid state circuits process these pulses into a signal that drives the pointer of the tachometer.
TCS Indicator
The malfunction indicator lamp traction control module controls the TCS indicator. If the EBTCM detects a malfunction with the TCS, the TCS indicator turns ON in order to alert the driver of the malfunction. A solid TCS indicator signifies the presence of a malfunction that affects the operation of the TCS.
For more information, refer to Warning Indicators in Antilock Brake System.
Turn Signal Indicators
The turn signal switch is used in order to control the turn signal lamps. At the same time, voltage is sent to the instrument cluster in order to turn ON the turn signal indicators. If the emergency flashers are turned ON, both of the turn signal indicators will flash.
For more information, refer to Exterior Lights in Electrical Diagnosis.
