Isuzu N-Series. Service manual - part 434

6E-72 EMISSION AND ELECTRICAL DIAGNOSIS

DTC-P31 Exhaust Gas Recirculation (EGR) Electronic Vacuum Regulating Valve (EVRV)
Solenoid Control Low Voltage

N6A1188E

EMISSION AND ELECTRICAL DIAGNOSIS 6E-73

Appearance of Electronic Vacuum Regulating
Valve (EVRV): Exhaust Gas Recirculation
(EGR) Sensor and Connector Name

EVRV: EGR

EVRV: EGR Connector

Measure Resistance at EVRV: EGR

Caution:
When measuring resistance with a circuit tester, be careful not to damage or deform the terminals.

N6A1189E

Legend

1. To EVRV: EGR
2. 2 pin

Connector No

Signal

1

GND

2

SIG

N6A1190E

Legend

1. Circuit tester

3. Measure resistance between connector pin

2. Remove EVRV wire harness

N6A1191E

6E-74 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

12

±1 (for 12 volt)

48

±2 (for 24 volt)

SIG 

←→ GND

1 

←→ Body

∞

SIG 

←→ Body

Step

Action

Value

YES

NO

1

Was the “on-board diagnostic (OBD) system
check” performed?

—

Go to Step 2

Go to self diag 

system check

2

1. Ignition “OFF”
2. Disconnect the EVRV from the wiring har-

ness connector.

3. Check the EVRV signal circuit between

the EVRV connector and the ECM for the
following condition.

• A short to ground
• An open circuit

4. Repair if necessary.

Has DTC31 been corrected?

—

Go to Step 7

Go to Step 3

3

Using the DVM, check the resistance of the
EVRV.

Does the DVM read the following Value?

12

Ω (for 12 

Volt)

48

Ω (for 24 

Volt)

Go to Step 4

Go to Step 5

4

1. Ignition “OFF”
2. Check an open circuit of the EVRV

ground circuit between the ECM and
EVRV connector.

3. Repair if necessary.

Has DTC31 been corrected?

—

Go to Step 7

Go to Step 6

5

Replace the EVRV.

Is the action complete?

—

Go to Step 7

Go to Step 6

6

Replace the ECM.

Is the action complete?

—

Go to Step 7

—

7

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

Is DTC31 all right under Scan Tool Check?

—

Go to Step 8

Go to Step 2

8

Is any current trouble other than DTC31 dis-
played by scan tool?

—

Go to trouble code 

section

Trouble code clear

EMISSION AND ELECTRICAL DIAGNOSIS 6E-75

DTC-P32 Exhaust Gas Recirculation (EGR) Electronic Vacuum Regulating Valve (EVRV)
Solenoid Control High Voltage

N6A1188E