2004 ISUZU TF SERIES Combination wiring

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-217
Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0172 B O2 Sensor System Too
Rich (Bank 1) 45
P0175 B O2 Sensor System Too
Rich (Bank 2) 1. No DTC relating to MAF sensor, IAT sensor, ECT sensor,
TPS, CMP sensor, CKP sensor, VSS, injector control
circuit, ignition control circuit, O2 sensor circuit low voltage
& high voltage (bank 1 & 2) and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is more than 600rpm.
3. Intake air temperature is more than 50
C.
4. Engine coolant temperature is between 35
C and 120
C.
5. Engine load is more than 20%.
6. EVAP purge solenoid valve on-duty is below 100%.
7. Air-fuel ratio correction volume is below 50% for 20
seconds. No fail-safe function.


CIRCUIT DESCRIPTION
To provide the best possible combination of driveability,
fuel economy, and emission control, a “closed loop"
air/fuel metering system is used. While in “closed loop,"
the Engine Control Module (ECM) monitors the heated
oxygen sensors (HO2S) signals and adjusts fuel
delivery based upon the HO2S signal voltages.
A
change made to fuel delivery will be indicated by the
long and short term fuel trim values which can be
monitored with a Tech 2. Ideal fuel trim values are
around 0%; if the HO2S signals are indicating a lean
condition the ECM will add fuel, resulting in fuel trim
values above 0%. If a rich condition is detected, the fuel
trim values will be below 0%, indicating that the ECM is
reducing the amount of fuel delivered. If an excessively
rich condition is detected on Bank 1, the ECM will se
t
DTC P0172 or P0175.
The ECM's maximum authority to control long term fuel
trim allows a range between –15% (automatic
transmission) or –12 (manual transmission) and +20%.
The ECM's maximum authority to control short term fuel
trim allows a range between –11% and +20%. The ECM
monitors fuel trim under various engine speed/load fuel
trim cells before determining the status of the fuel trim
diagnostic.

DIAGNOSTIC AIDS
Check for the following conditions:
 Poor connection at ECM – Inspect harness
connectors for backed-out terminals, imprope
r
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
 Damaged harness –Inspect the wiring harness fo
r
damage. If the harness appears to be OK, observe
the HO2S display on the Tech 2 while moving
connectors and wiring harnesses related to the
engine harness. A change in the display will indicate
the location of the fault.

3B-40 POWER-ASSISTED STEERING SYSTEM



430RX005-X
14. Remove steering column cover.
15. Disconnect the wiring harness connectors located
under the steering column then remove combination
switch and SRS coil assembly.

Installation
1. Align the setting marks made when removing then
install steering wheel.
Refer to the adjustment method in case a mark is
not attached in this section.
NOTE: Confirm SRS and Horn harness connector is
fixed by the steering wheel.
RTW33BSH000601

CAUTION: Never apply force to the steering wheel in
direction of the shaft by using a hammer or othe
r
impact tools in an attempt to remove the steering
wheel. The steering shaft is designed as an energy
absorbing unit.
2. Tighten the steering wheel fixing nut to the specified
torque.
Torque: 31 - 39 N





m (3.2 – 4.0 kg





m/23 - 29 lb ft)
3. Support the inflator module and carefully connect the
SRS connector and horn lead. (with SRS air bag)
060R300041
4. Connect the horn leads at center of wheel. (without
SRS air bag)
NOTE: Horn leads is letting a bracket top pass.
(Plastic type steering wheel only)



RTW43BSH000301

3B-46 POWER-ASSISTED STEERING SYSTEM


CAUTION:
When turning the SRS coil
counterclockwise to full, stop turning if resistance
is felt. Forced further turning may damage the cable
in the SRS coil.
(with SRS air bag)
826RW014
Legend
(1) Neutral mark





430RX005-X
16. Remove steering column cover.
17. Disconnect the wiring harness connectors located
under the steering column then remove combination
switch and SRS coil assembly. (with SRS air bag)
NOTE: The SRS coil is a part of the combination switch
assembly, which can not be replaced separately.
Therefore, be sure not to remove the SRS coil from the
combination switch assembly. (with SRS air bag)
430R300014

Installation
1. Install the combination switch assembly with SRS
coil. (with SRS air bag)
2. Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark. (with SRS
air bag)


3. Connect the wiring harness connectors located at
the base of steering column.
4. Install the air conditioning lower duct.
5. Install the steering column cover.
CAUTION:
When installing the steering column
cover, be sure to wire (through each harness) as
illustrated so that the harness starter switch,
combination switch and SRS coil may not catch
wiring.
(with SRS air bag)
825RS048

3B-52 POWER-ASSISTED STEERING SYSTEM

430R300007
17. Remove steering column cover.
18. Disconnect the wiring harness connectors located
under the steering column.
19. Remove the combination switch assembly with SRS
coil.
NOTE: The SRS coil is a part of the combination switch
assembly, which can not be replaced separately.
Therefore, be sure not to remove the SRS coil from the
combination switch assembly. (with SRS air bag)
430R300014
20. Turn the ignition switch to the ACC position.

21. Insert a pin (1) into the hole and push on it. Pull the
key cylinder free.
P1010003

Installation
1. Install lock cylinder assembly.
2. Install the combination switch assembly with SRS
coil. (with SRS air bag)
3. Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark. (with SRS
air bag)
CAUTION:
When turning the SRS coil
counterclockwise to full, stop turning if resistance
is felt. Forced further turning may damage the cable
in the SRS coil.
(with SRS air bag)
826RW014
Legend
(1) Neutral mark

3B-58 POWER-ASSISTED STEERING SYSTEM

16. Remove steering column cover.
17. Disconnect the wiring harness connectors located
under the steering column.
18. Remove the combination switch assembly with SRS
coil.
NOTE: The SRS coil is a part of the combination switch
assembly, which can not be replaced separately.
Therefore, be sure not to remove the SRS coil from the
combination switch assembly.
430R300014
19. Remove snap ring.
20. Remove cushion rubber.
21. Remove shift lock cable (For A/T).
22. Disconnect the starter switch harness connecto
r
located under the steering column, then remove
lock cylinder assembly.

23.
Apply a setting mark (1) across the universal joint
and transfer gear to reassemble the parts in thei
r
original position, then remove steering column
assembly and second shaft.
NOTE: A setting mark can be easily made if the shaft is
withdrawn a little by loosening the steering shaft
universal joint.



RTW33BSH000501

Inspection
If the abnormal conditions are found through inspection,
replace the steering column assembly.

Column Capsule
Check capsules on steering column bracket assembly;
all must be securely seated in bracket slots and
checked for any loose conditions when pushed or pulled
by hand.
431RW030

POWER-ASSISTED STEERING SYSTEM 3B-59

Check clearance between capsule and bracket. If must
be within 1mm (0.039 in).
431RW031

Column Universal Joint (between the
power steering unit and the steering shaft)
If the resistance is felt when checked by rotate the joint,
replace the lower second steering shaft.

Shaft Universal Joint (between the lower
second steering shaft and the second
steering shaft)
If the resistance is felt when checked by rotate the joint,
replace the second steering shaft assembly.

Tilt Mechanism
Tilt mechanism should moves smoothly.
While locked the tilt mechanism, be sure the steering
column latch securely by pushing the steering wheel
upward and downward.

Installation
1. Align the setting marks on the second steering shaft
and the steering column assembly (applied at
disassembly).
2. Connect the steering column assembly to the second
steering shaft. Tighten the bolts to the specified
torque.
Torque: 26 - 36 N




m (2.7 – 3.7 kg




m/20 - 27 lb ft)
3. Thread the steering column assembly through the
hole in the dashpanel. Temporarily tighten the
steering column and the second steering shaft fixing
bolt.
4. Connect the lower second steering shaft and the
second steering shaft. Tighten the universal joint
bolts to the specified torque.
Torque: 26 - 36 N




m (2.7 – 3.7 kg




m/20 - 27 lb ft)
5. Tighten the steering column fixing bolt (pedal brkt
side) to the specified torque (This bolt was
temporarily tighten in Step 3).
Torque: 18 -23 N




m (1.8 – 2.3 kg




m/13 - 17 lb ft)

6. Tighten the second steering shaft fixing bolt to the
specified torque (This bolt was temporarily tightened
in Step 3)
Torque: 18 -23 N




m (1.8 – 2.3 kg




m/13 - 17 lb ft)
7. Tighten the steering column fixing bolt (dashpanel
side) to the specified torque (This bolt was
temporarily tighten in Step 3).
Torque: 18 -23 N




m (1.8 – 2.3 kg




m/13 - 17 lb ft)
8. Install combination switch and SRS coil assembly.
After installation of combination switch assembly,
connect the combination switch wiring harness
connector and the SRS 2-way connector located
under the steering column.