Oxygen Sensor Output Voltage (without Plugs) Standard: 0.2 V or less

If the reading is within range (with plugs: 0.7 V or more, without plugs: 0.2 V or less), the oxygen sensor is good. If the reading is without range, replace the oxygen sensor (see Oxygen Sensor Removal/Installation in the Electrical System chapter).

Oxygen Sensor Circuit

1. ECU

2. Oxygen Sensor

3. Water-proof Joint E

4. Water-proof Joint D

5. Oxygen Sensor Heater Fuse 10 A

6. Main Fuse 30 A

7. Battery

8. Frame Ground

9. Joint Connector

 

 

Stick Coils #1, #2: (Service Code 51, 52)

Stick Coil #1: Service Code 51

Stick Coil #2: Service Code 52

CAUTION

Never drop the stick coils, especially on a hard sur- face. Such a shock to the stick coil can damage it.

Stick Coil Removal/Installation

• Refer to the Stick Coil (Ignition Coil together with Spark Plug Cap) Removal/Installation in the Electrical System

chapter.

Stick Coil Input Voltage Inspection

NOTE

○Be sure the battery is fully charged.

• Turn the ignition switch OFF.

• Remove the ECU (see ECU Removal). Do not disconnect

the ECU connector.

• Connect a digital voltmeter [A] as shown, with the needle adapter set [B].

○Measure the input voltage to each primary winding of the

ignition coils with the engine stopped, and with the con-

nectors joined.

• Turn the ignition switch ON.

Stick Coil Input Voltage at ECU Connections for Stick Coil #1

Meter (+) → BK lead (terminal 43) Meter (–) → BK/Y lead (terminal 51)

Connections for Stick Coil #2

Meter (+) → BK/G lead (terminal 52) Meter (–) → BK/Y lead (terminal 51)

Input Voltage at ECU

Standard: Battery Voltage (12.8 V or more)

If the reading is out of the standard, check the wiring (see next wiring diagram).

If the reading is good, the input voltage is normal. Crank the engine, and check the peak voltage of the stick coils (see Stick Coil Primary Peak Voltage in the Electrical Sys- tem chapter) in order to check the primary coils.

 

 

Stick Coils #1, #2: (Service Code 51, 52)

Stick Coil Circuit

1. ECU

2. Water-proof Joint C

3. Stick Coils

4. Engine Stop Switch

5. Ignition Switch

6. Ignition Fuse 10 A

7. Main Fuse 30 A

8. Battery

9. Frame Ground

10. Joint Connector

 

 

Radiator Fan Relay (Service Code 56)

Radiator Fan Relay Removal/Installation

• Radiator fan relay is built in the relay box.

• Remove the relay box (see Relay Box Removal in the

Electrical System chapter).

Radiator Fan Relay Inspection

• Refer to the Relay Circuit Inspection in the Electrical Sys- tem chapter.

• Remove the relay box and ECU (see ECU Removal). Do

not disconnect the relay box and ECU connectors. Check

the wiring for continuity, using the following diagram.

If wiring and radiator fan relay are good, check the ECU for its ground, and power supply (see ECU Power Supply Inspection). If the ground and power supply are good, replace the ECU (see ECU Removal/Installation).

Radiator Fan Relay Circuit

1. ECU

2. Water-proof Joint C

3. Water-proof Joint B

4. Radiator Fan Fuse 15 A

5. Relay Box

6. Radiator Fan Relay

7. Main Fuse 30 A

8. Battery

9. Frame Ground

10. Joint Connector

 

 

Subthrottle Valve Actuator (Service Code 62)

Subthrottle Valve Actuator Removal

CAUTION

Do not remove the subthrottle valve actuator [A] since it has been adjusted and set with precision at the factory. Never drop the throttle body assy, especially on a hard surface. Such a shock to the actuator can damage it.

Subthrottle Valve Actuator Audible Inspection

NOTE

○Be sure the battery is fully charged.

• Turn the ignition switch ON and ensure that the actuator valves open and close (make light sounds) several times

within seconds, and then close at the idle throttle opening position.

• Turn the ignition switch OFF.

If the actuator does not work as described above, do the

visual inspection.

Subthrottle Valve Actuator Inspection

• Remove the air cleaner housing (see Air Cleaner Housing Removal).

• Turn the ignition switch ON.

• Check to see that all the subthrottle valves [A] open and

close smoothly.

If the subthrottle valves do not operate, check the actuator internal resistance (see Subthrottle Valve Actuator Resis- tance Inspection).

 

Subthrottle Valve Actuator Resistance Inspection

• Turn the ignition switch OFF.

• Remove the air cleaner housing (see Air Cleaner Housing

Removal).

• Disconnect the subthrottle valve actuator connector [A].

 

• Connect a digital meter to the subthrottle valve actuator connector [A].

• Measure the subthrottle valve actuator resistance.

Subthrottle Valve Actuator Resistance Connections: BK lead [1] ←→ P lead [2]

G lead [3] ←→ W/BL lead [4] Standard: About 5.5 ~ 7.5 kΩ