Isuzu N-Series. Manual - part 290

HSA (HILL START AID) 5A5-39

N5A3029E

5A5-40 HSA (HILL START AID)

Symptom: HSA Does not Release Though the Vehicle Is Operated to Start (HSA Indicator
Lamp Remains ON)

Step

Action

Value

YES

NO

1

Is the continuity (resistance) of neutral switch
normal?

—

Go to Step2

Go to Step3

2

Is the clutch sensor properly installed (check
the trouble code “08”)?

—

Go to Step4

Go to Step5

3

Repair or replace the neutral switch.

Is the repair completed?

—

Go to Step4

Go to Step3

4

Is the resistance between the clutch sensor
terminals within the specified range?

—

Go to Step6

Go to Step7

5

After installation, perform the initial adjust-
ment.

Is the repair completed?

—

Go to Step8

Go to Step8

6

Replace the HSA control unit.

Is the repair completed?

—

Go to Step8

Go to Step6

7

Replace the clutch sensor.

Is the repair completed?

—

Go to Step8

Go to Step7

8

After HSA repair, make sure no trouble is
found during self-diagnosis.

Is this step completed?

—

—

Go to Step8

HSA (HILL START AID) 5A5-41

N5A3030E

5A5-42 HSA (HILL START AID)

Symptom: HSA Does not Release Though the Parking Brake Is Applied

Step

Action

Value

YES

NO

1

Is the continuity (resistance) of the parking
brake switch normal?

—

Go to Step2

Go to Step3

2

Measure the battery voltage between the
parking brake switch connector terminal 1 “N-
6” and the body ground (with the connector
disconnected). Is the measurement com-
pleted?

20V or more

Go to Step4

Go to Step5

3

Repair or replace the parking brake switch.

Is the repair completed?

—

Go to Step4

Go to Step3

4

Measure the battery voltage between the HSA
control unit connector terminal 2 “B-285” and
the body ground (with connector discon-
nected). Is the measurement completed?

20V or more

Go to Step6

Go to Step7

5

Repair the improper connection or open circuit
between 5 “B-51” (meter) and 1 “N-6”.

Is the repair completed?

—

Go to Step7

Go to Step5

6

Replace the HSA control unit.

Is the repair completed?

—

Go to Step8

Go to Step6

7

Repair the open circuit between 5 “B-51”
(meter) and 2 “B-285”.

Is the repair completed?

—

Go to Step8

Go to Step7

8

After HSA repair, make sure no trouble is
found during self-diagnosis.

Is this step completed?

—

—

Go to Step8