cruise control ISUZU TF SERIES 2004 User Guide

8B-8 CRUISE CONTROL SYSTEM
Cruise Control Unit




RTW3A0SH001101
Removal
1. Disconnect the battery ground cable.
2. Remove the dash side trim panel (LH) (1).
3. Disconnect the connector.
4. Remove a fixing nut to remove the cruise control unit (2).

Installation
To install, follow the removal steps in the reverse order.

Cruise Actuator

Actuator Cable Diagram





RTW3A0SF000301
Legend
(1) Cruise Actuator Assembly
(2) Cruise Control Cable

(3) Accelerator Cable
(4) Throttle Link (Cruise Control Side)

CRUISE CONTROL SYSTEM 8B-9


RTW3A0SH001001
Removal
1. Disconnect the battery cable.
2. Remove the cruise actuator Assembly (4).

Disconnect the connector (3).

Remove the cable end (1) from the throttle link (cruise
control side).

Loosen a fixing nut of the cruise control cable (2).

Remove fixing screws of the actuator (5).


Installation
To install, follow the removal steps in the reverse order, noting
the following point.
1. Take care not to bend the cable excessively.





RTW3A0SH001501
Adjustment
After installing the cruise actuator, the following steps must be
carried out for cruise control cable adjustment.
1. Install the cruise control cable end (3) to the throttle link (4).
2. Put the screw portion of the cable in the bracket (5).
3. Put the nut (1) to the bracket and then tighten the nut (2).
CAUTION: Don't move a position of the nut (1) from
supplied condition.
4. If the distance between the throttle link (4) and the throttle
link lever (6) is out of the specified range, loosen the nut (2)
to adjust it.

Mode Switch


Removal and Installation
Refer to the Mode Switch removal and installation steps in
Automatic Transmission section.

8B-10 CRUISE CONTROL SYSTEM
Diagnosis
The cruise control unit uses the cruise main indicator light and diagnosis the failure, when the control unit detects
abnormality on the table below.

PART POSSIBLE CAUSE DETECTION PERIOD DTC
Actuator Motor system short circuit Energizing motor 1-1
Clutch system short circuit Energizing clutch 1-2
Clutch system open circuit Energizing clutch 1-2
Mechanical defect Cruise controlling 1-3
Close side of motor system open circuit Cruise controlling 1-1
Cruise control unit Close side of motor system open circuit While starter sw on 1-4
Clutch output abnormality While starter sw on 1-4
Vehicle speed sensor Signal of vehicle speed disconnection Cruise controlling 2-1
Signal of vehicle speed abnormality Cruise controlling 2-1
Switch Turning on switch at all times While starter sw on 3-1
Turning on switch at the same time While starter sw on 3-1
DTC : Diagnostic Trouble Code

DTC Display Condition
1. With the vehicle stationary and the ignition ON, activate the ‘Cruise Cancel’ switch three times within 2 seconds.
2. If there are no DTC’s stored in the Cruise control unit, the LED on the Cruise Main switch will blink rapidly (2Hz).
3. Any DTC’s stored in the Cruise control unit will be displayed by the CRUISE SET warning lamp in the meter
cluster.
4. Read the set DTC’s by referring to then charts on this page.

NOTE:

The DTC display mode will be aborted if either the vehicle speed rises above 10km/h or the RESUME switch is
operated.

The control module stores the DTC in a ‘volatile’ memory – that is the memory is only active while the ignition is
ON.
Turning the ignition to the OFF position will clesr any stored DTC’s.

CRUISE CONTROL SYSTEM 8B-11
DTC Display Format
1. When no DTCs are detected. (The unit : sec.)







F08RW003
2. When two or more DTCs are detected. (The unit : sec.)






F08RW009

8B-12 CRUISE CONTROL SYSTEM

CIRCUIT DIAGRAM



RTW48AXF003801

CRUISE CONTROL SYSTEM 8B-13
DTC 1–1 Motor System Short Circuit

Step Action Value(s) YES NO
1 1. Turn the starter switch off.
2. Disconnect the actuator connector C-119.
3. Measure resistance between actuator side
connector terminal 1 and 2.
If control plate position is fully opened or fully
closed, resistance can not be measure.
Is there resistance within range specified in the
value(s) column?





More than
4.2






Go to Step 2





Replace the
actuator
2 Measure continuity between harness side connector
C-119 terminal 1 and the ground, terminal 2 and the
ground, and terminals 1 and 2.
Are the results same as specified in the value(s)
column?


No
continuity


Replace the
control unit

Repair or
replace the
harness

8B-14 CRUISE CONTROL SYSTEM
DTC 1–2 Clutch System Open or Short Circuit

Step Action Value(s) YES NO
1
1. Turn the starter switch off.
2. Disconnect the actuator connector C–119.
3. Measure resistance between actuator side
connector terminal 3 and 4.
Is there resistance within range specified in the
value(s) column?



34.7 –
42.4




Go to Step 2



Replace the
actuator
2
1. Disconnect the brake switch connector C–44.
2. Check continuity between switch side connector
terminal 3 and 4.
Is there continuity between terminals?


—


Go to Step 3

Replace the
switch
3
1. Reconnect the brake switch connector C–44.
2. Check continuity between harness side connector
C–120 terminal 6 and connector C–44 terminal 3,
connector C–119 terminal 4 and connector C–120
terminal 8.
Is there continuity between terminals?




—




Go to Step 4



Replace open
circuit
4 Check continuity between harness side connector
C–119 terminal 3 and the ground, connector C–119
terminal 4 and the ground, connector C–120
terminal 6 and the ground.
Are the results same as specified in the value(s)
column?



No
continuity



Replace the
control unit



Repair short
circuit

CRUISE CONTROL SYSTEM 8B-15
DTC 1–3 Mechanical Defect

Step Action Value(s) YES NO
1
1. Turn the starter switch off.
2. Disconnect the actuator connector C–119.
3. Connect the battery positive terminal with the
actuator side connector terminal 3 and the battery
negative terminal with terminal 4.
Does the control plate move by hand?




—



Replace the
actuator




Go to Step 2
2 Connect the battery positive terminal with the
actuator side connector terminal 1 and 3, and the
battery negative terminal with terminal 2 and 4.
Does the control plate move to full open side?


—


Go to Step 3

Replace the
actuator
3 Connect the battery positive terminal with the
actuator side connector terminal 2 and 3, and the
battery negative terminal with terminal 1 and 4.
Does the control plate move to full close side?


—


Go to Step 4

Replace the
actuator
4 Is there continuity between harness side connector
C–119 terminal 1 and connector C–120 terminal 7,
connector C–119 terminal 2 and connector C–120
terminal 15?


—

Replace the
control unit
Repair or
replace
harness

8B-16 CRUISE CONTROL SYSTEM
DTC 1–4 Close Side of Motor System Open Circuit

Step Action Value(s) YES NO
1
1. Turn the starter switch off.
2. Disconnect the actuator connector C–119.
3. Measure resistance between actuator side
connector terminal 1 and 2.
If control plate position is fully opened or fully
closed, resistance can not be measured.
Is there resistance within range specified in the
value(s) column?





More than
4.2






Go to Step 2





Replace the
actuator
2 Is there continuity between harness side connector
C–119 terminal 1 and connector C–120 terminal 7,
harness side connector C–119 terminal 2 and
connector C–120 terminal 15?


—

Replace the
control unit
Repair or
replace the
harness

CRUISE CONTROL SYSTEM 8B-17
DTC 2–1 Signal of Vehicle Speed Malfunction
Step Action Value(s) YES NO
1 Check the DTC for engine.
Is the vehicle speed sensor DTC set?
—
Go to DTC for
engine


Go to Step 2

2 Check continuity between harness side connector
E–44 terminal 3 and connector C–120 terminal 9.
Is there continuity between terminals?

—

Go to Step 3
Replace open
circuit
3 Check the continuity between harness side
connector E–44 terminal 3 and ground, connector
C–120 terminal 9 and ground.
Are the results same as specified in the value(s)
column?



No continuity



Replace the
control unit


Repair short
circuit