The magnetic fields of the 2 coils, the 0 kPa (0 psi) coil and the 551.6 kPa (80 psi) coil, move the pointer of the oil pressure gauge. The magnetic fields interfere with each other, because the 2 coils are at right angles. Battery voltage is available from GAUGES fuse 4 through CKT 39 (PNK) to the instrument cluster when the ignition switch is in the RUN position or in the START position. Current flows through the 0 kPa (0 psi) coil which places the pointer at 0 kPa (0 psi), when the 551.6 kPa (80 psi) coil has little current. When the current through the 551.6 kPa (80 psi) coil is high, the pointer moves toward the 551.6 kPa (80 psi) indication.

The current that passes through the 0 kPa (0 psi) coil has 2 paths to ground. Some of the current passes through the fixed resistance of the 551.6 kPa (80 psi) coil to ground G101 through CKT 451 (BLK/WHT). The remainder of the current goes to ground through the variable resistance of the oil pressure sensing element. The oil pressure sensing element in the fuel pump switch and the oil pressure gauge sensor in gasoline vehicles or in the engine oil pressure indicator sender in diesel vehicles produces a resistance of approximately 0 Ω when the oil pressure is zero, and 88 Ω when the oil pressure is 551.6 kPa (80 psi). When the oil pressure is high, more current flows through the 551.6 kPa (80 psi) coil and the pointer moves to 551.6 kPa (80 psi).

The CHECK GAUGES lamp lights when a low oil pressure condition is present. The setpoint is at approximately 9.6 Ω or 34.5 kPa (5 psi).

The oil pressure gauge's accuracy is adequate for normal operator usage in that the oil pressure gauge provides a reasonably accurate indication of the engine oil pressure which identifies sudden or long term changes. The sensing element's response is essentially linear over the operating range. The gauge accuracy specification is 3.5 degrees (angular) at 0 kPa (0 psi) and 7 degrees at 551.6 kPa (80 psi). Changes in battery voltage do not affect the gauge accuracy.

The PRNDL display light indicates the gear position as selected for the automatic transmission. The PRNDL circuit board, which is part of the instrument cluster, has power from TRANS fuse 24 when the ignition switch is in the RUN position. Voltage is available through CKT 1020 (PNK). The circuit board has ground in CKT 451 (BLK/WHT) to ground G101. The module receives 4 grounded inputs from the park/neutral position (PNP) switch. Depending on the gear position selected for the automatic transmission, a combination of 2-4 of these inputs have ground through the PNP switch. The PRNDL circuit board evaluates the inputs and lights the appropriate display. For a discussion of the PRNDL indication illumination, refer to Interior Lights Dimming Circuit Description in Lighting Systems.

The magnetic fields of the 2 coils, the 40°C (100°F) coil and the 126.7°C (260°F) coil, move the pointer of the temperature gauge. The magnetic fields interfere with each other, because the 2 coils are at right angles. Battery voltage is available from the GAUGES fuse 4 through CKT 39 (PNK) to the instrument cluster when the ignition switch is in the RUN position or in the START position. Current flowing through the 40°C (100°F) coil places the pointer at the 40°C (100°F) (low temperature) indication. When the current through the 126.7°C (260°F) coil is high, the pointer moves toward the 126.7°C (260°F) (high temperature) indication.

The current passing through the 126.7°C (260°F) coil has 2 paths to ground. Some of the current passes through the fixed resistance of the 40°C (100°F) coil to ground G101 through CKT 451 (BLK/WHT). The remainder of the current goes to ground through the variable resistance of the temperature sensor. The engine coolant temperature gauge sensor produces a resistance of approximately 1305 Ω when the temperature is 40°C (100°F). With this high resistance, more current flows through the 40°C (100°F) coil and the pointer moves toward the 40°C (100°F) indication. the sensor's resistance is approximately 61.9 Ω at 118°C (245°F). With this low resistance, more current passes through the temperature sensor and not the 40°C (100°F) coil. The pointer moves toward 126.7°C (260°F).

A high temperature condition lights the CHECK GAUGES indicator. The setpoint is at approximately 61.9 Ω or 118°C (245°F).

The temperature gauge's accuracy is adequate for normal operator usage. The gauge provides a reasonably accurate indication of the engine coolant temperature. The gauge identifies sudden or long-term changes. The sensing element's response is non-linear over the operating range. This response limits accuracy. The gauge accuracy specification is for 3.5 degrees (angular) at 126.7°C (260°F) and for 7 degrees at 40°C (100°F). Changes in the battery voltage do not affect the gauge accuracy.

The magnetic fields of the 2 coils, the E coil and the F coil, move the pointer of the fuel gauge. The 2 coils are at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES fuse 4 through CKT 39 (PNK) to the instrument cluster when the ignition switch is in the RUN position or in the START position. The current flowing through the E coil places the pointer at E (empty) when little current flows through the F coil. When the current flow through the F coil is high, the pointer moves toward the F (full) indication.

The current that passes through the E coil has 2 paths to ground. Some of the current passes through the fixed resistance of the F coil and to ground G101 through CKT 451 (BLK/WHT). The rest of the current goes to ground through the variable resistance produced by the vehicle control module (VCM) in gasoline vehicles or the fuel sender buffer module in diesel vehicles. The fuel pump and sender in gasoline vehicles or the fuel tank level sender in diesel vehicles produces a resistance of approximately 40 Ω when the fuel tank is empty. With this low resistance, most current passes through the fuel sender and not through the F coil. When the tank is full, the fuel sender's resistance is approximately 250 Ω. With this high resistance, more current flows through the F coil and the pointer moves to the F indication.

The fuel gauge's accuracy is adequate for normal operator usage. The fuel gauge provides a reasonable accurate indication of the level in the fuel tank. The fuel sender buffer module provides anti-sloshing in order to increase the fuel gauge performance. Changes in the battery voltage do not affect the gauge accuracy. However, non-linear construction in the fuel tank influences the accuracy of the gauge.

The voltmeter indicates battery voltage when the ignition switch is in the RUN position or in the START position. The voltmeter measures generator voltage when the engine runs. The normal generator voltage is 14 volts. The battery voltage without the engine running depends upon the ambient temperature and may be as low as 9.6 volts. GAUGES fuse 2 through CKT 39 (PNK) supplies voltage to the voltmeter. The signal coil indicator has ground through CKT 451 (BLK/WHT) to ground G101.

The CHECK GAUGES lamp lights when either the engine oil pressure is at or below approximately 34.5 kPa (5 psi), or whenever the engine coolant temperature is at or over approximately 118°C (245°F). When the ignition switch is in the RUN position or the START position, the check gauges lamp driver receives power from GAUGES fuse 4 through CKT 39 (PNK). The lamp driver has ground in CKT 451 (BLK/WHT) at ground G101. The CHECK GAUGES lamp remains lit after the engine start until the engine oil pressure exceeds the low oil pressure setpoint.

GAUGES fuse 4 powers the speedometer and the odometer solid state logic through CKT 39 (PNK) to the instrument cluster. The speedometer and the odometer solid state logic receives a square wave 4000 pulse per mile (PPM) from the vehicle control module (VCM) in gasoline vehicles, or from the vehicle speed sensor (VSS) buffer in diesel vehicles through CKT 389 (DK GRN). The solid state electronics position the speedometer pointer in response to the pulse rate. The electronics also drive the odometer indication in response the pulse rate over time. The speedometer's rated accuracy at 104.6 km/h (65 mph) is within 3.2 km/h (2 mph) or 101.4-107.8 km/h (63-67 mph). At 32.2 km/h (20 mph), the rated accuracy is within 6.4 km/h (4 mph) or 25.7-38.6 km/h (16-24 mph). Variations in voltage and inaccuracies in the other circuit components may increase the error.

The low coolant lamp in diesel vehicles illuminates in order to indicate that the radiator has a low coolant level. Battery voltage is available at the engine coolant level indicator module through CKT 39 (PNK) from GAUGES fuse 4 when the ignition switch is in the RUN position or in the START position. The module has ground at ground G201 through CKT 150 (BLK). The module senses a variable resistance to ground at the low engine coolant level indicator sensor through CKT 1478 (LT GRN). The sensor has a resistance of 50,000 Ω or more when the coolant level is low. The resistance decreases to about 10,000 Ω when the radiator is full. The sensor has ground at G109 in CKT 151 (BLK/WHT). The low coolant lamp lights when the resistance to ground is approximately 50,000 Ω or more.