Pinpoint Test I: Tachometer System

NOTE: Go to TROUBLE SHOOTING before starting pinpoint test. Identify system where problem is located. Find symptom in trouble shooting and go to specific pinpoint test step as directed by trouble shooting procedure.

Check Fuse

Check the 10A METER fuse located in the interior fuse panel. Is the fuse OK? If yes, go to step 4 . If no, go to next step.

Check System

Turn key OFF. Replace the 10A METER fuse. Turn key ON. Does the fuse fail again? If yes, go to next step. If no, go to step 4 .

Check For Short To Ground

Turn key OFF. Remove the 10A METER fuse. Remove the instrument cluster. Disconnect the black 12-pin instrument cluster connector. Measure the resistance of the (Gray/Blue) wire between the right terminal of the 10A METER fuse and ground. Is the resistance less than 5 ohms? If yes, service the (Gray/Blue) wire. If no, replace the 10A METER fuse. Go to next step. See WIRING DIAGRAMS .

Check Power Supply To Instrument Cluster

Turn key OFF. Disconnect the black 12-pin instrument cluster connector. Turn key ON. Measure the voltage on the (Gray/Blue) wire at Terminal No. 2I of the black 12-pin instrument cluster connector. Is the voltage greater than 10 volts? If yes, go to next step. If no, service the (Gray/Blue) wire between the interior fuse panel and the instrument cluster. See WIRING DIAGRAMS .

Check Power Supply To Tachometer

Turn key OFF. Reconnect the black 12-pin instrument cluster connector. Key ON. Measure the voltage on Terminal B of the tachometer on the back of the instrument cluster. Terminals are labeled on the back of the instrument cluster. Is the voltage greater than 10 volts? If yes, go to next step. If no, replace the instrument cluster printed circuit board.

Check Tachometer Ground

Turn key OFF. Leave the instrument cluster connected. Measure the resistance of the (Black/Red) wire between the Terminal G of the tachometer on the back of the instrument cluster and ground. Terminals are labeled on the back of the instrument cluster. Is the resistance less than 5 ohms? If yes, go to step 8 . If no, go to next step. See WIRING DIAGRAMS .

Check Instrument Cluster Ground

Turn key OFF. Disconnect the black 12-pin instrument cluster connector. Measure the resistance of the (Black/Red) wire between Terminal No. 2C of the black 12-pin instrument cluster connector and ground. Is the resistance less than 5 ohms? If yes, replace the instrument cluster printed circuit board. If no, service the (Black/Red) wire. See WIRING DIAGRAMS .

Check Tachometer Signal From PCM

Turn key OFF. Remove the instrument cluster. Leave the instrument cluster connected. Connect the analog Rotunda Inductive Dwell-Tach-Volts Ohms Tester (059-00010), or equivalent, to measure engine speed. Turn key ON, engine running. Measure the voltage on Terminal S of the tachometer on the back of the instrument cluster (terminals are labeled on the back of the instrument cluster) at the following engine speeds. See TACHOMETER SIGNAL FROM PCM . Are the voltages OK? If yes, replace the tachometer. If no, go to next step.

TACHOMETER SIGNAL VOLTAGE FROM PCM

Engine Speed	Voltage
1000 RPM	1.69 volts
1500 RPM	2.64 volts
2000 RPM	3.44 volts
2500 RPM	4.50 volts
3000 RPM	5.22 volts

Check Instrument Cluster Printed Circuit Board

Turn key OFF. Remove the instrument cluster. Measure the resistance of the circuit between Terminal S of the tachometer and Terminal No. 2A of the black 12-pin instrument cluster connector. Is the resistance less than 5 ohms? If yes, see POWERTRAIN DIAGNOSTIC PROCEDURES to diagnose the powertrain control module. If no, replace the instrument cluster printed circuit board.