Isuzu KB P190. Service manual — part 164

BRAKE CONTROL SYSTEM 5A-63

Step Action Value(s)

Yes

No

8

Does the sensor rotor have missing tooth or saw-
toothed?

-

Go to Step 14

Go to Step 9

9

1. Clear the DTC.

2. Test run the vehicle, and check the DTC.

Is the DTC displayed repeatedly?

-

Go to Step 18

Go to Step 17

10

Is the wheel speed sensor damaged or saw-toothed?

-

Go to Step 15

Go to Step 16

11

Repair or replace the wheel bearing.

Is the action complete?

-

Verify repair

-

12

Repair or replace the rear left speed sensor or the
sensor rotor.

Is the action complete?

-

Verify repair

-

13

Repair the rear left speed sensor or the sensor rotor.

Is the action complete?

-

Verify repair

-

14

Replace the sensor rotor.

Is the action complete?

-

Verify repair

-

15

Replace the rear left wheel speed sensor.

Is the action complete?

-

Verify repair

-

16

Repair or replace the rear left speed sensor circuits.

Is the action complete?

-

Verify repair

-

17

Check the connection btween the EHCU and the rear
left wheel speed sensor and repair as necessary
Refer to "Note on Intermittents".

Is the action complete?

-

Verify repair

-

18 Replace

EHCU.

Note: Check the EHCU type for specification, when
the EHCU is replaced.

(Specification ; 2WD model or 4WD model)

Is the action complete?

-

Verify repair

-

5A-64 BRAKE CONTROL SYSTEM

DTC C0238 (Flash Code 38) Front Speed Sensor Correlation

Step Action Value(s) Yes

No

1

Were the steps of the “Basic Diagnostic Flow Chart”
performed?

-

Go to Step 2

Go to Basic

Diagnostic

Flow Chart

2

1. Check for the tire size of each wheels.

2. If the tire size is different, replace the tire.

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 3

3

1. Check for the gear ratio of a front axle differential

gear and a rear axle differential gear.

2. If the gear ratio is different, repair the gear ratio.

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 4

4

Select “Display DTCs” with the Tech 2.

Note: Perform the various tests (actuator test, test
run, brake test, etc.) then observe the DTC with a
Tech 2.

Are any DTCs stored?

-

Go to Step 5

Verify repair

5

1. Check for a poor connection at the wheel speed

sensor harness connector.

2. Check installation condition for wheel speed sensor.

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 6

6

1. Check condition for sensor rotor.

2. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 7

7

1. Ignition “OFF” disconnect the EHCU and wheel

speed sensor.

2. Check the circuit between EHCU and wheel speed

sensor. (short ground, or short to voltage)

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 8

8

1.

Ignition

“OFF”.

2. Check the EHCU circuit for an open, short to

ground, or short to voltage. Also, check the EHCU
ignition feed circuit for an open or short to ground
and the EHCU ground circuit for an open or short to
voltage.

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 9

9

1. Ignition “ON”, engine “OFF”.

2. Select “Display DTCs” with the Tech 2.

Note: Perform the various tests (actuator test, test
run, brake test, etc.) then observe the DTC with a
Tech 2.

Are any DTCs stored?

-

Go to Step 10

Verify repair

BRAKE CONTROL SYSTEM 5A-65

Step Action Value(s) Yes

No

10 Replace

EHCU.

Note: Check the EHCU type for specification, when
the EHCU is replaced.

(Specification; 2WD model or 4WD model)

Was the action complete?

-

Verify repair

-

5A-66 BRAKE CONTROL SYSTEM

DTC C0241 (Flash Code 41) Front Right Hold Solenoid Valve Circuit
DTC C0242 (Flash Code 42) Front Right Release Solenoid Valve Circuit

RTW75ALF000301

Step Action Value(s) Yes

No

1

Were the steps of the “Basic Diagnostic Flow Chart”
performed?

-

Go to Step 2

Go to Basic

Diagnostic

Flow Chart

2

1.

Ignition

“OFF”.

2. Check the EHCU circuit for an open, short to

ground, or short to voltage. Also, check the EHCU
ignition feed circuit for an open or short to ground
and the EHCU ground circuit for an open or short to
voltage.

3. If a problem is found, repair as necessary.

Was a problem found?

-

Verify repair

Go to Step 3