Instrument Cluster Circuit Description Domestic

Oil Pressure Gauge

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 ohms when the oil pressure is zero, and 88 ohms 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 ohms 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.

PRNDL Display

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.

Temperature Gauge

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 ohms 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 ohms 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 ohms 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.

Fuel Gauge

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 4 ohms 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 90 ohms. 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.

Voltmeter

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.

CHECK GAUGES Lamp

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.

Speedometer/Odometer

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.

Low Engine Coolant Level Indicator

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 ohms or more when the coolant level is low. The resistance decreases to about 10,000 ohms 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 ohms or more.

Instrument Cluster Circuit Description Export Gasoline

Oil Pressure Gauge

The magnetic fields of the 0 psi and the 80 psi coils moves the pointer of the oil pressure gauge. The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition switch is in the RUN or START position. If there is little current through the 80 psi coil, current flows through the 0 psi coil, placing the pointer at 0 psi. If the current though the 80 psi coil is high, then the pointer moves toward the 80 psi indication.

The current that passes through the 0 psi coil has 2 paths to ground. Some of the current can pass through the fixed resistance of the 80 psi coil to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the oil pressure sensing element. The oil pressure sensing in the fuel pump switch and oil pressure gauge sensor produces a resistance of approximately 0 ohms when the oil pressure is 0 and 88 ohms at 80 psi. Most current passes through the oil pressure sensing element and not the 80 psi coil with the low resistance. If the oil pressure is high, the following conditions occur:

The CHECK GAUGES lamp lights when a low oil pressure condition occurs. The setpoint is 9.6 ohms or 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 from which sudden or long term changes may be identified. The sensing element's response is linear over the operating range. The gauge accuracy specification is for 3.5 degrees (angular) at 0 psi and for 7 degrees at 80 psi. Gauge accuracy is not affected by changes in battery voltage.

PRNDL Display

The PRNDL displays light to indicate the gear position selected for the automatic transmission. The PRNDL circuit board is part of the instrument cluster. The PRNDL is powered from the TRANS Fuse 24 when the ignition is turned to the RUN position. The circuit board is grounded by the CKT 451 (BLK/WHT) wire to Ground G101. The module receives 4 grounded inputs from the park/neutral position switch. A combination of 2 -- 4 of these inputs are grounded by the park/neutral position switch depending on the gear position selected for the automatic transmission. The PRNDL circuit board evaluates the inputs and light the appropriate display. Refer to Interior Lights Dimming Schematics for information on PRNDL indication illumination.

Temperature Gauge

The pointer of the temperature gauge is moved by the following components:

The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition is in the RUN or START position. Current flows through the 38°C (100°F) coil which places the pointer at 38°C (100°F) (low temperature) if there is little current through the 93°C (260°F) coil. The pointer moves toward the 93°C (260°F) (high temperature) indication if the current through the 93°C (260°F) is high.

The current that passes through the 93°C (260°F) coil has 2 paths to ground. Some of the current can pass through the fixed resistance of the 38°C (100°F) coil and to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the temperature sensor. The engine coolant temperature gauge sensor produces a resistance of approximately 1305 ohms when the temperature is 38°C (100°F). With this high resistance, more current flows through the 38°C (100°F) coil and the pointer moves toward 38°C (100°F). The sensor's resistance is approximately 61.9 ohms at 118°C (245°F). With this low resistance, more current passes through the temperature sensor and not the 38°C (100°F) coil. The pointer moves toward the 93°C (260°F).

The high temperature conditions causes the CHECK GAUGES lamp to light. The setpoint is at approximately 61.9 ohms or 118°C (245°F).

The accuracy of the temperature gauge is adequate for normal operator usage because the temperature gauge provides a reasonably accurate indication of the engine coolant temperature from which sudden or long term changes may be identified. The response of the sensing element is non- linear over the operating range. The non-linear response of the sensing element limits the accuracy of the temperature gauge. The gauge accuracy specification is for the following measurements:

The gauge accuracy is not affected by changes in the battery voltage.

Fuel Gauge

The fuel gauge pointer is moved by the following coils:

The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition switch is in the RUN or START position. Current flows through the E coil which places the pointer at E (empty) if there is little current through the F coil. If the current through the F coil is high, then 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 can pass through the fixed resistance of the F coil and to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the fuel sender element and the fuel sender buffer module. The fuel sender element in the fuel pump and fuel sender produces a resistance of approximately 4 ohms when the fuel tank is empty. With this low resistance, most of the current passes through the fuel sender and not the F coil. If the tank is full, then the resistance of the fuel sender is approximately 90 ohms. With this high resistance, more current flows through the F coil and the pointer moves to E.

The accuracy of the fuel gauge is adequate for normal operator usage. The fuel gauge provides a reasonably accurate indication of the level in the fuel tank. The fuel sender buffer module is used for anti - sloshing in order to increase the accuracy of the fuel gauge. The gauge accuracy is not affected by changes in the battery voltage. The accuracy of the fuel gauge can be influenced by the non - linear construction of the fuel tank.

Voltmeter

The voltmeter indicates battery voltage when the ignition switch is in one of the following positions:

The voltmeter measures the generator voltage when the engine is running. The normal generator voltage is 14 V. The battery voltage when the engine is not running will depend upon the ambient temperature and may be as low as 9.6 V. The voltage is supplied to the voltmeter from the GAUGES Fuse 4 through the CKT 39 (PNK) wire. Grounding for the single coil indicator is through the CKT 451 (BLK/WHT) wire to Ground G101.

Check Gauges Lamp

The CHECK GAUGES lamp lights when one or more of the following conditions occur:

In order to power the check gauges lamp driver, the ignition switch must be in one of the following positions:

Power to the lamp driver is from the GAUGES Fuse 4 through the CKT 39 (PNK) wire. The lamp driver is grounded by the CKT 451 (BLKL/WHT) wire at Ground G101. The CHECK GAUGES lamp will remain lighted after engine start until the engine oil pressure exceeds the low oil pressure setpoint.

Speedometer/Odometer

The solid state logic of the speedometer and odometer is powered from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster. The speedometer/odometer receives a square wave 4000 PPM (Pulses Per Mile) pulse from the vehicle control module (VCM) through the CKT 389 (DK GRN) wire. The solid state electronics positions the speedometer pointer in response to the pulse rate. The electronics also drives the odometer indication in response to the pulse rate over time.

The rated accuracy of the speedometer at 105 kmh (65 mph) is 101-108 kmh (63- 67 mph). At 32 kmh (20 mph), the rated accuracy is 26-39 kmh (16-24 mph). Error in the speedometer/odometer may be caused by the following conditions:

Instrument Cluster Circuit Description Diesel

Oil Pressure Gauge

The magnetic fields of the 0 psi and the 80 psi coils moves the pointer of the oil pressure gauge. The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition switch is in the RUN or START position. If there is little current through the 80 psi coil, current flows through the 0 psi coil, placing the pointer at 0 psi. If the current though the 80 psi coil is high, then the pointer moves toward the 80 psi indication.

The current that passes through the 0 psi coil has 2 paths to ground. Some of the current can pass through the fixed resistance of the 80 psi coil to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the oil pressure sensing element. The oil pressure sensing element in the engine oil pressure indicator sender produces a resistance of approximately 0 ohms when the oil pressure is 0 and 88 ohms at 80 psi. Most current passes through the oil pressure sensing element and not the 80 psi coil with the low resistance. If the oil pressure is high, the following conditions occur:

The CHECK GAUGES lamp lights when a low oil pressure condition occurs. The setpoint is 9.6 ohms or 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 from which sudden or long term changes may be identified. The sensing element's response is linear over the operating range. The gauge accuracy specification is for 3.5 degrees (angular) at 0 psi and for 7 degrees at 80 psi. Gauge accuracy is not affected by changes in battery voltage.

PRNDL Display

The PRNDL displays light to indicate the gear position selected for the automatic transmission. The PRNDL circuit board is part of the instrument cluster. The PRNDL is powered from the TRANS Fuse 24 when the ignition is turned to the RUN position. The circuit board is grounded by the CKT 451 (BLK/WHT) wire to Ground G101. The module receives 4 grounded inputs from the park/neutral position switch. A combination of 2-4 of these inputs are grounded by the park/neutral position switch depending on the gear position selected for the automatic transmission. The PRNDL circuit board evaluates the inputs and light the appropriate display. Refer to Interior Lights Dimming Schematics for information on PRNDL indication illumination.

Temperature Gauge

The pointer of the temperature gauge is moved by the following components:

The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition is in the RUN or START position. Current flows through the 38°C (100°F) coil which places the pointer at 38°C (100°F) (low temperature) if there is little current through the 93°C (260°F) coil. The pointer moves toward the 93°C (260°F) (high temperature) indication if the current through the 93°C (260°F) is high.

The current that passes through the 93°C (260°F) coil has 2 paths to ground. Some of the current can pass through the fixed resistance of the 38°C (100°F) coil and to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the temperature sensor. The engine coolant temperature gauge sensor produces a resistance of approximately 1305 ohms when the temperature is 38°C (100°F). With this high resistance, more current flows through the 38°C (100°F) coil and the pointer moves toward 38°C (100°F). The sensor's resistance is approximately 61.9 ohms at 118°C (245°F). With this low resistance, more current passes through the temperature sensor and not the 38°C (100°F) coil. The pointer moves toward the 93°C (260°F).

The high temperature conditions causes the CHECK GAUGES lamp to light. The setpoint is at approximately 61.9 ohms or 118°C (245°F).

The accuracy of the temperature gauge is adequate for normal operator usage because the temperature gauge provides a reasonably accurate indication of the engine coolant temperature from which sudden or long term changes may be identified. The response of the sensing element is non - linear over the operating range. The non - linear response of the sensing element limits the accuracy of the temperature gauge. The gauge accuracy specification is for the following measurements:

The gauge accuracy is not affected by changes in the battery voltage.

Fuel Gauge

The fuel gauge pointer is moved by the following coils:

The 2 coils are oriented at right angles so that the magnetic fields interfere with each other. Battery voltage is available from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster when the ignition switch is in the RUN or START position. Current flows through the E coil which places the pointer at E (empty) if there is little current through the F coil. If the current through the F coil is high, then 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 can pass through the fixed resistance of the F coil and to Ground G101 through the CKT 451 (BLK/WHT) wire. The rest of the current will go to ground through the variable resistance of the fuel sender element and the fuel sender buffer module. The fuel sender element in the fuel tank level sender produces a resistance of approximately 4 ohms when the fuel tank is empty. With this low resistance, most of the current passes through the fuel sender and not the F coil. If the tank is full, then the resistance of the fuel sender is approximately 90 ohms. With this high resistance, more current flows through the F coil and the pointer moves to E.

The accuracy of the fuel gauge is adequate for normal operator usage. The fuel gauge provides a reasonably accurate indication of the level in the fuel tank. The fuel sender buffer module is used for anti - sloshing in order to increase the accuracy of the fuel gauge. The gauge accuracy is not affected by changes in the battery voltage. The accuracy of the fuel gauge can be influenced by the non - linear construction of the fuel tank.

Voltmeter

The voltmeter indicates battery voltage when the ignition switch is in one of the following positions:

The voltmeter measures the generator voltage when the engine is running. The normal generator voltage is 14 V. The battery voltage when the engine is not running will depend upon the ambient temperature and may be as low as 9.6 V. The voltage is supplied to the voltmeter from the GAUGES Fuse 4 through the CKT 39 (PNK) wire. Grounding for the single coil indicator is through the CKT 451 (BLK/WHT) wire to Ground G101.

Check Gauges Lamp

The CHECK GAUGES lamp lights when one or more of the following conditions occur:

In order to power the check gauges lamp driver, the ignition switch must be in one of the following positions:

Power to the lamp driver is from the GAUGES Fuse 4 through the CKT 39 (PNK) wire. The lamp driver is grounded by the CKT 451 (BLKL/WHT) wire at Ground G101. The CHECK GAUGES lamp will remain lighted after engine start until the engine oil pressure exceeds the low oil pressure setpoint.

Speedometer/Odometer

The solid state logic of the speedometer and odometer is powered from the GAUGES Fuse 4 through the CKT 39 (PNK) wire to the instrument cluster. The speedometer/odometer receives a square wave 4000 PPM (Pulses Per Mile) pulse from the vehicle speed sensor buffer (VSSB) through the CKT 389 (DK GRN) wire. The solid state electronics positions the speedometer pointer in response to the pulse rate. The electronics also drives the odometer indication in response to the pulse rate over time.

The rated accuracy of the speedometer at 105 kmh (65 mph) is 101-108 kmh (63-67 mph). At 32 kmh (20 mph), the rated accuracy is 26-39 kmh (16- 24 mph). Error in the speedometer/odometer may be caused by the following conditions:

Low Engine Coolant Level Indicator

The low coolant lamp illuminates in order to indicate a low coolant level in the radiator. Battery voltage is available at the engine coolant level indicator module through the CKT 39 (PNK) wire from the GAUGES Fuse 4 when the ignition switch is in one of the following positions:

The module is grounded at Ground G101 by the CKT 150 (BLK) wire. The module senses a variable resistance to ground at the low engine coolant level indicator sensor through the CKT 1478 (LT GRN) wire. The sensor has a resistance of 50,000 ohms or more when the coolant level is low. The resistance decreases to 10,000 ohms when the radiator is full. The sensor is grounded at Ground G109 by the CKT 151 (BLK/WHT) wire. The low coolant lamp lights when the resistance to ground is approximately 50,000 ohms or more.