Isuzu KB P190. Manual — part 29

1-82 HEATER AND AIR CONDITIONING

RTW710SH000801

Fan switch and A/C switch

Check for continuity between fan switch and A/C switch side
connector terminals.
(A/C (4JA1-T, 4JJ1-TC Standard Output, 4JJ1-TC High
Output, 4JK1-TC High Output))

B-13 B-57

Terminal

No.

SW.
position

1

2

3

4

5

6

2

3

1

5

6

OFF

1

2

3

(FAN SW.)

4

OFF

(A/C SW.)

ON

RUW710SH000501

(A/C (4JH1-TC, C24SE)).

B-13 B-57

Terminal

No.

SW.
position

1

2

3

4

5

6

1

5

6

OFF

1

2

3

(FAN SW.)

4

OFF

(A/C SW.)

ON

D08R300070

(Cooler)

B-13 B-57

Terminal

No.

SW.
position

1

2

3

4 5 6 2

3

10

11

OFF

1

2

3

(FAN SW.)

4

OFF

(A/C SW.)

ON

HEATER AND AIR CONDITIONING 1-83

RTW410SH000201

Electronic thermostat

Check for continuity between electronic thermostat side
connector terminals.
(A/C)

(Cooler)

1-84 HEATER AND AIR CONDITIONING

RTW4A0SH000201

Triple Pressure switch

Disconnect pressure switch connector and check for continuity
between pressure switch side connector terminal.

825r300045

Heater and thermo switch relay.

Check for continuity between the relay terminals.

1 - 5 ⋅⋅⋅⋅⋅ No continuity

(When battery voltage is applied between 2 - 4 )

1 - 5

⋅⋅⋅⋅⋅ Continuity

825r300023

Check for continuity between the relay terminals.

1 - 2 ⋅⋅⋅⋅⋅ No continuity

(When battery voltage is applied between 3 - 4 )

1 - 2

⋅⋅⋅⋅⋅ Continuity

HEATER AND AIR CONDITIONING 1-85

TROUBLESHOOTING

FAN CONTROL KNOB (FAN SWITCH)

Current flows to the blower motor through the Heater & A/C relay (X-11) to activate the rotation of the blower motor
by turning “ON” the fan control knob (fan switch). Blower motor speed is controlled in stages by the resistor, by
operating the switch from “LOW” to “HIGH.”

RTW710LF004201