Isuzu N-Series. Service manual - part 462

6E-184 EMISSION AND ELECTRICAL DIAGNOSIS

Resistance value

Notice:
Resistance value is difference according to the engine temperature (condition of engine warming up).

Inspection Point

Resistance Value

(k

Ω)

Reference

Connector

Pin No.

2 pin Black

2 

←→ 1

37 to 44 (for 12 volt)

159 to 169 (for 24 volt)

SIG 

←→ GND

1 

←→ Body

∞

SIG 

←→ Body

Step

Action

Value

YES

NO

1

Was the “Diagnostic system check” per-
formed?

—

Go to Step 2

Go to diagnostic 

system check

2

Using the DVM, check the resistance of the
VSV.

Does the DVM read the following Value?

37 — 44

Ω

159 — 169

Ω

Go to Step 3

Go to Step 4

3

1. Ignition “OFF”.
2. Disconnect the ECM connector from

ECM.

3. Check the short to voltage of VSV circuit

between the ECM and VSV connector.

4. Repair if necessary.

Has DTC 32 been corrected?

—

Go to Step 6

Go to Step 5

4

Replace the VSV.

Is the action complete?

—

Go to Step 6

—

5

Replace the ECM.

Is the action complete?

—

Go to Step 6

—

6

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

Does DTC 32 come normal condition?

—

Go to Step 7

Go to Step 2

7

Is any current trouble other than DTC 32 dis-
played by indicator light?

—

Go to trouble code 

section

Trouble code clear

EMISSION AND ELECTRICAL DIAGNOSIS 6E-185

DTC-41 Quick On Start (QOS) Relay Control Circuit Low Voltage

N6A1333E

6E-186 EMISSION AND ELECTRICAL DIAGNOSIS

Location of Relay

Legend

1. Relay box (Installed on the left side rear of the 

cab)

N6A1184E

NO

RELAY NAME

X-20

Glow plug

X-21

Starter

X-22

Marker lamp

X-23

Rear fog

X-24

A/C COMP, 4WD ind. lamp

X-25

Exh, Brake control

X-26

CSD, A/C ON SIGNAL

X-27

Condenser fan

X-28

Exh. Brake cut

EMISSION AND ELECTRICAL DIAGNOSIS 6E-187

Inspection for prestroke power cut relay

Resistance value

Legend

A. QOS relay

N6A1214E

Legend

A. QOS relay

N6A1215E

Inspection Point

Resistance

Reference

Inspection 
relay unit

4 

←→  5

23  (

Ω) (for 12 volt)

100 (

Ω) (for 24 volt)

2 

←→ 3

∞

Not be supplied electricity to coil

Below 0.5 (

Ω)

Be supplied electricity to coil