Tachometer Malfunction

DESCRIPTION

In this circuit, the meter CPU receives engine speed signals from the ECM using the CAN communication system. The meter CPU displays the engine speed, which is calculated based on the data received from the ECM.

WIRING DIAGRAM
PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication DTC is output (See page ).

Result

Result	Proceed to
CAN communication DTC is not output	A
CAN communication DTC is output	B

B

GO TO CAN COMMUNICATION SYSTEM

A

1. PERFORM ACTIVE TEST USING TECHSTREAM (TACHO METER OPERATION)

(a) Use the Active Test to check the operation of the tachometer (See page ).

Combination Meter

Tester Display	Test Part	Control Range	Diagnostic Note
Tacho Meter Operation	Tachometer	0, 1000, 2000, 3000, 4000, 5000, 6000, 7000 (rpm)	Confirm that the vehicle is stopped with the engine idling.

OK:

Tachometer indication is normal.

NG

REPLACE COMBINATION METER ASSEMBLY

OK

1. READ VALUE USING TECHSTREAM (ENGINE RPM)

(a) Use the Data List to check the engine speed (See page ).

Combination Meter

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Engine Rpm	Engine speed/Min.: 0 rpm, Max.: 12800 rpm	600 to 700 rpm (When idling)	If the data received from the ECM exceeds the range that can be displayed on the meter, the meter continues to display the maximum value.

OK:

Engine speed displayed on the Techstream is almost the same as the tachometer indication.

(b) Record the engine speed displayed on the Techstream.

HINT:

Check the engine speed when the engine is fully warmed up, and the air conditioning and all electrical accessories are off.

NG

REPLACE COMBINATION METER ASSEMBLY

OK

1. READ VALUE USING TECHSTREAM (ENGINE SPEED)

(a) Use the Data List to check the engine speed (See page ).

Engine and ECT

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Engine Speed	Engine speed/Min.: 0 rpm, Max.: 16383 rpm	600 to 700 rpm (When idling)	-

OK:

Engine speed displayed on the Techstream is almost the same as the previously recorded Techstream value (Body Electrical / Combination Meter / Data List / Engine Rpm).

NG

GO TO SFI SYSTEM

OK

1. REPLACE ECM

(a) Replace the ECM with a new or normally functioning one (See page ).

OK:

The operation of the tachometer returns to normal.

OK

END

NG

REPLACE COMBINATION METER ASSEMBLY