VI. Filling brake fuid and bleadAfter replace HECU, besides filling and blead as per routine brake system, also blead the secondary circuit of
HECU. Steps are as follows if fault diagnosis instrument is used for operation:MK-60 ABS system -Removal and Installation5-119Perform charging blead according to routine brake system until no bubble
appears in transparent rubber tube
Connect fault diagnosis instrument and diagnostic interface
Select function 04, press OK key to confirm
Step down brake pedal and keep rebound of hydraulic pump work pedal
Release the brake, loosen left and right front brake tongs venting screws,
press " " key
Step on brake pedal for 10 times, tighten up left and right front brake
tongs venting screws, press " " key
Repeat the above Step I II III for seven times, then press " " key.
Screen displays end of exhaust, press " " key to return to "function
selection" menu
Select function 06, press OK key to exit diagnosis modeEnd
4. Knocking sensor
(1) Knocking sensor is a vibration acceleration sensor. Mounted on engine cylinder body. Sensing element of
the sensor is a piezocrystal. Vibration of engine cylinder body is transferred to piezocrystal via mass block in the
sensor. Since pressure generated by vibration of mass block is applied to piezocrystal, it generates voltage on two
polar planes and turns vibration signal into voltage signal for output.5-122Symptom
Poor accelerationPossible cause
Various liquids, such as engine oil, cooling fluid, brake fluid, water etc
contact the sensor for a long time, which cause corrosion to the sensor. Mounting torque: 20 ± 5 N.M
Repair precautions: sensor must be fitted closely to cylinder body with its metal surface, any type of washer
is not permitted for installation. For wiring of sensor signal cables, note that do not let resonance occur to signal
cables, otherwise they might be broken. Energizing of high voltage between sensor 1 # and 2 # pins must be
avoided, otherwise piezoelectric element might be damaged.
(2) Simple measuring method:
(Remove joint) turn digital multimeter to ohm position, connect two meter pens with sensor 1 #, 2 # pin
respectively, its resistance value at room temperature should exceed 1M ohm. Turn digital multimeter to millivolt
position, use a hand hammer to tap near knocking sensor, now voltage signal output should be available.
5. Oxygen sensor
(1) Its sensing element is a ceramic tube, outside is open to exhaust, inside is open to atmosphere. When
temperature of sensing ceramic tube reaches 350°C, it will have the characteristic of solid state electrolyte. Just
utilizing this characteristic, it converts concentration difference of oxygen into electric potential difference, thus
forms electrical signal output. If mixed gas is a bit concentrated, inside and outside oxyanion concentration
difference of ceramic tube is high, electric potential difference is a bit high.
A large number of oxyanions move from inside to outside, output voltage is high (approximate 900mV); if
mixed gas is a bit thin, inside and outside oxyanion concentration difference of ceramic tube is low, electric
potential difference is low, only a small quantity of oxyanions move from inside to outside, output voltage is low
(approximate 100mV).
Possible cause
1. humid water vapor ingresses inside of sensor, temperature
changes rapidly, probe is broken.
2. oxygen sensor "is poisoned". (Pb, S, Br, Si) Symptom
Poor idle speed, poor speedup, tail gas
overproof, too high oil consumption1 2 3 4Oxygen sensor Mounting torque: 40-60 N.m
Repair precautions: it is prohibited to use cleaning fluid, oily liquid or volatile solid on oxygen sensor during
repair.
(2) Simple measuring method:
(Remove joint) turn digital multimeter to ohm position, connect
two meter pens with sensor 1# (white), 2# (white) pin respectively, its
resistance value at room temperature is 1- 6 ohm.
(Connect joint) in idle speed condition, when oxygen sensor
reaches its working temperature of 350°C, turn digital multimeter to
DC voltage position, connect two meter pens with sensor 3# (grey),Engine EFI System-Engine EFI System
It is mainly used to install the pipes and accessories of the brake system and clutch system.
5. Front wall upper assembly
The front wall upper assembly includes left/right hinge base mounting plate big assembly, front wall upper
front cover big assembly, VIN number mounting plate, and front wall upper rear cover big assembly etc.
It forms a high-stiffness frame structure together with the engine compartment assembly and the front wall
lower plate assembly. It can generate strong resistant to the transverse collision and rolling deformation. It can also
separate the engine compartment form the cabin, preventing the odor entering into the cabin. Consequently, it can
isolate the noise, heat and vibration.(2) Floor Assembly The floor assembly is the base work of the main structure. It is a key component that connects various
assemblies and carries the load. The vehicle performance is subject to its strength and stiffness. For the floor
assembly, see the Fig. 5-3.
The floor assembly includes front floor assembly and rear floor assembly. The front floor mid-block goes
through a ridgy channel in longitudinal direction. It can increase the longitudinal rigidity together with the lower
floor longitudinal beam. The space below under the channel is used to install various parts and components, such
as transmission gearshift rod, parking brake cable, discharge pipe with three-way catalytic converter etc. In the
cabin, there is carpet and muffle pad. The floor frame structure is made up of front floor left/right frame, front floor
main plate assembly, front floor mid-bridge assembly, rear frame assembly, rear floor rear block assembly, rear
floor mid-block assembly and longitudinal beam etc. These parts and components provide strong and reliable carry
capacity and ensure that the vehicle meets the strict driving requirement on the body.Fig. 5-3 Floor Assembly
1. Front floor left/right frame 2. Front floor main plate assembly 3. Longitudinal beam rear block 4. Rear frame assembly
5. Rear floor rear block assembly 6. Rear floor mid-block assembly 7. Front floor mid-bridge assemblySurvey -Body Structure7-371
2
133
5
6
