Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 1120

ELECTRICAL-BODY AND CHASSIS  8-237

TACHOMETER

1. Tachometer does not function when engine is running

Checkpoint

Trouble Cause

Countermeasure

Replace the tacho sensor, or

repair open circuit or

connector contact

Tacho sensor malfunction, or

open circuit or poor connector

contact

NG

Replace the tachometer

Tachometer function

Tachometer malfunction

NG

OK

Pulse between connector

B-24

 and the ground when

engine is running (Should be
pulse present)

2. Meter needle fluctuates

(May be wide fluctuation)

Replace the tachometer

Tachometer malfunction

NG

Use a meter tester to check

the tachometer function

8-238  ELECTRICAL-BODY AND CHASSIS

TEMPERATURE GAUGE AND THERMO UNIT

1. No temperature indicates at all

Checkpoint

Trouble Cause

Countermeasure

Replace the thermo unit

Thermo unit malfunction

NG

Replace the temperature

gauge

Gauge function
1. Disconnect the unit

connector then connect
3.4W bulb to wire harness
side with ground

2. Check indicating point

when starter SW. is ON
position (Temperature
should indicate)

Gauge malfunction

Repair open circuit or

connector contact

Continuity between 1 

E-8

and 6 

B-24

Open circuit or poor connector

contact

NG

NG

OK

OK

Thermo unit continuity
between connector 

E-8

 and

the ground

2. Temperature gauge incorrect readings in all ranges

Replace the thermo unit

Thermo unit malfunction

NG

Thermo unit resistance
between connector 1 

E-8

and the ground when
disconnecting the connector
(Specified resistance should
indicate)

ELECTRICAL-BODY AND CHASSIS  8-239

FUEL GAUGE AND FUEL TANK UNIT

1. No fuel level indicates at all

Checkpoint

Trouble Cause

Countermeasure

Replace the tank unit

Open circuit inside the tank

unit

NG

Thermo unit malfunction

Replace the fuel gauge

Fuel gauge function
1. Disconnect the tank unit

connector then connect
3.4W bulb to wire harness
side

2. Check indicating point

when starter SW. is ON
position (Fuel level should
indicate)

Gauge malfunction

Repair open circuit or

connector contact

Continuity between

connectors 11 

B-23

 and 1

F-1

Open circuit or poor connector

contact

NG

NG

OK

OK

Tank unit continuity between

connector 1 

F-1

 and ground

2. Fuel gauge gives incorrect readings in all ranges

Replace the tank unit

Tank unit malfunction

NG

Tank unit resistance position
with the float at checking
points (Specified resistance
should indicate)

8-240  ELECTRICAL-BODY AND CHASSIS

WARNING AND INCIDATOR LIGHT

1. When the parking brake lever is pulled, the indicator light does not light up

Checkpoint

Trouble Cause

Countermeasure

Replace or reinstall the bulb

Bulb burned out or loose

contact

NG

Adjust or replace the parking

brake SW.

Parking brake SW. installation

position and function

Incorrect SW. adjustment or

poor SW. point contact

Repair open circuit or

connector contact

Continuity between the
parking brake SW. connector
1 

C-39

 (4

×4: 1 

R-4

) and 12

B-23

Open circuit or poor connector

contact

NG

NG

OK

OK

Brake indicator light bulb

continuity

Replace the parking brake

SW.

Continuity between the
parking brake SW. connector
1 

C-39

 (4

×4: 1 

R-4

) and

the ground when the parking
brake is operated

Parking brake SW.

malfunction

NG

OK