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Instrument Cluster Circuit

Disconnect instrument cluster harness connectors "A", "B", "C" and "D". See Fig 1. Using DVOM, test each circuit from harness side of appropriate connector under condition as specified. See INSTRUMENT CLUSTER CIRCUIT VALUES  table. If values are not as specified, repair circuits as necessary. See WIRING DIAGRAMS .

INSTRUMENT CLUSTER CIRCUIT VALUES

Circuit Application Tester Connection Condition Circuit Value
GAUGE Fuse D2 & Ground Ignition Switch In ON Position Battery Voltage
GAUGE Fuse D2 & Ground Ignition Switch In LOCK, ACC Or START Position Zero Volts
Light Control Rheostat D3 & Ground Headlights On & Rheostat In Any Position Except Fully Clockwise 5 Volts Or Greater
Light Control Rheostat D3 & Ground Headlights On & Rheostat In Fully Clockwise Position Zero Volts
Igniter D9 & Ground Engine Running Voltage Varies
Ground D10 & Ground Constant Continuity
DOME Fuse D11 & Ground Constant Battery Voltage
Starter Relay D12 & Ground Ignition Switch In START Position Battery Voltage
Starter Relay D12 & Ground Ignition Switch In LOCK, ACC Or ON Position Zero Volts
Speed Sensor D13 & D14 Ignition On & Drive Shaft Turning Less Than One Volt To 4.5-5.5 Volts
Speed Sensor D13 & D14 Ignition On & Drive Shaft Stationary Zero Volts
Odometer & Twin Trip Switch D14 & D19 Clock/Ambient Temp. Switch In ON Position Continuity
Odometer & Twin Trip Switch D14 & D19 Clock/Ambient Temp. Switch In OFF Position No Continuity
Odometer & Twin Trip Switch D14 & B10 A/B Switch In ON Position Continuity
Odometer & Twin Trip Switch D14 & B10 A/B Switch In OFF Position No Continuity
Odometer & Twin Trip Switch D14 & B11 Reset Switch In ON Position Continuity
Odometer & Twin Trip Switch D14 & B11 Reset Switch In OFF Position No Continuity
Door Courtesy Switch D15 & Ground Driver's & Passenger's Door Open Continuity
Door Courtesy Switch D15 & Ground Driver's & Passenger's Door Closed No Continuity
Fuel Gauge Sending Unit D22 & C15 Float In FULL Position About 3 Ohms
Fuel Gauge Sending Unit D22 & C15 Float In 1/2 Position About 30.8 Ohms
Fuel Gauge Sending Unit D22 & C15 Float In EMPTY Position About 110 Ohms
Ground D23 & Ground Constant Continuity
Ground A2 & Ground Constant Continuity
Engine Oil Level Warning Switch A8 & Ground Oil Temp. Less Than 131°F (55°C) Continuity
Engine Oil Level Warning Switch A8 & Ground Oil Temp. Greater Than 131°F (55°C) With Float Up Continuity
Engine Oil Level Warning Switch A8 & Ground Oil Temp. Greater Than 131°F (55°C) With Float Down No Continuity
PNP Switch B6 & Ground Shift Lever In "P" Position Battery Voltage
PNP Switch B7 & Ground Shift Lever In "R" Position Battery Voltage
PNP Switch B8 & Ground Shift Lever In "N" Position Battery Voltage
PNP Switch A10 & Ground Shift Lever In "D" Position Battery Voltage
PNP Switch B9 & Ground Shift Lever In "3" (SC300) Or "4" (SC400) Position Battery Voltage
PNP Switch B12 & Ground Shift Lever In "2" (SC300) Or "3" (SC400) Position Battery Voltage
HEAD Fuse (SC400) B2 & Ground Headlights On & Dimmer Switch In HI Or FLASH Position Battery Voltage
HEAD Fuse (SC400) B2 & Ground Headlights On & Dimmer Switch In ON Position Zero Voltage
Headlight Dimmer Switch B3 & Ground Constant (SC300) Battery Voltage
Headlight Dimmer Switch B3 & Ground Dimmer Switch In HI Or FLASH Position (SC400) Battery Voltage
Headlight (SC400) B4 & Ground Constant Continuity
Transmission Shift Pattern Select Switch B13 & Ground Ignition On & Select Switch In PWR Position Battery Voltage
Transmission Shift Pattern Select Switch B13 & Ground Ignition On & Select Switch In NORM Position Zero Volts
Washer Level Warning Switch C5 & Ground Float Down Continuity
Washer Level Warning Switch C5 & Ground Float Up No Continuity
Brake Fluid Level Warning Switch C8 & Ground Float Down Continuity
Brake Fluid Level Warning Switch C8 & Ground Float Up No Continuity
Parking Brake Switch C8 & Ground Pedal Depressed Continuity
Parking Brake Switch C8 & Ground Pedal Released No Continuity
ECU-B Fuse C10 & Ground Constant Battery Voltage
Generator "L" Terminal C12 & Ground Engine Off Continuity
Generator "L" Terminal C13 & Ground Engine Running Battery Voltage
Low Oil Pressure Warning Switch C14 & Ground Engine Running No Continuity
Low Oil Pressure Warning Switch C14 & Ground Engine Off Continuity
Fuel Gauge Sending Unit C16 & Ground Fuel Tank Full No Continuity
Fuel Gauge Sending Unit C16 & Ground Fuel Tank Empty Continuity
Fig 1: Identifying Instrument Cluster Harness Connector Terminals
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