Isuzu N-Series. Manual - part 459

Go to self diagnos-

tic system check

1. Memory DTC to ECM.
2. Clear DTC.
3. Ignition “OFF”
4. Disconnect the ECT sensor.
5. Ignition “ON”, Engine “OFF”

Does indicate DTC 14? (Ignore DTC 13)

—

Go to Step 3

Go to Step 6

1. Ignition “OFF”
2. Check Connector ECT Sensor Harness

for interterminal short.

3. Repair if necessary.

Was ECT Sensor connector shorted?

—

Go to Step 4

1. Ignition “OFF”
2. Check the ECM connector terminal short.
3. Repair if necessary.

Was ECM terminal shorted?

—

Go to Step 5

1. Disconnect the ECM.
2. Check if ECT sensor signal circuit for a

short to ground or a short to ground cir-
cuit.

3. Repair if necessary.

Is ECT sensor signal circuit shorted to
ground?

—

Go to Step 7

1. Ignition “OFF”
2. Replace the ECT Sensor.

Is the action complete?

—

—

1. Replace the ECM.

Is the action complete?

—

—

1. Reconnect all the connectors removed.
2. Ignition “ON”, Engine “OFF”

Does DTC 14 come normal condition?

—

Go to Step 9

Is any current trouble other than DTC 14 dis-
played by indicator light?

—

Go to trouble code

section

Trouble code clear

EMISSION AND ELECTRICAL DIAGNOSIS 6E-173

DTC-21 Rack Sensor Circuit Low Voltage

Location of Rack Sensor Connector

Legend

1. OSC (red)

3. GND (black)

2. MDL (white)

4. Rack sensor

N6A1319E

N6A1320E

6E-174 EMISSION AND ELECTRICAL DIAGNOSIS

Connector Name of Rack Sensor

Notice:
Mark “___” on connector which is plugged, therefore,
should be confirmed to be played.

Relation Between Connector Number and Signal
Name

Connector

Signal name

Wire color

Rack sensor (OSC)

Rack sensor (GND)

Rack sensor (MDL)

N6A1321E

EMISSION AND ELECTRICAL DIAGNOSIS 6E-175

Step

Action

Value

YES

Was the “Diagnostic system check” per-
formed?

—

Go to diagnostic

system check

1. Check harness side power source circuit

and signal circuit for GND short.

2. Repair if necessary.

Has DTC21 been corrected?

—

Go to Step 3

Disconnect Sensor Connector.
Jumper RACK+ and RACK signal.

Free from trouble now?
Ignore code 22.

—

Go to Step 4

Go to Step 6

1. Apply 5V to RACK+ TERMINAL.

Measure RACK SIG Voltage.

Is RACK SIG VOLTAGE as specified?

0.9 — 2.0V

(Idling speed)

Go to Step 7

Go to Step 5

1. Check Rack Sensor Harness Signal Cir-

cuit and power source for GND short.
Check signal circuit for disconnect.

2. Repair if necessary.

Free from trouble now?

—

Go to Step 7

1. Check harness signal circuit and power

source circuit for disconnect.

2. Repair if necessary.

Free from trouble now?

—

Go to Step 9

1. Check the iron core of RACK Sensor for

damage, seizure, and wear.

2. After check, repair if necessary.

Was there any trouble in the iron core (RACK
end) inside RACK Sensor?

—

1. Replace the RACK Sensor.

Is the action complete?

—

—

1. Replace the ECM.

Is the action complete?

—

—

1. Reconnect all the connectors removed.
2. Ignition “ON”, Engine “OFF”

Is DTC 21 all right under Scan Tool Check?

—

Go to Step 11