125 

heating element of oxygen 
sensor  

conductor. The engine is started and running at idling speed. Note: this value is related to 
temperature.  

10.4  Oxygen 

sensor 

Insulated resistance of 
heating element to 
primary element 

Close ignition, disconnect socket connector of oxygen sensor. Measure signal line (black) and 
signal cathode conductor (grey) of oxygen sensor and two white conductors one by one with 
multimeter. Note: this value is related to temperature. 

＞

30MΩ at -20 ; 

℃ ＞

10MΩ 

at 350 ; 

℃

＞

100KΩ at 

850 .

℃

 

10.5  Oxygen 

sensor 

Reference voltage of 
controller terminal 10   

Close ignition, plug in controller, and disconnect socket connector of oxygen sensor, and 
voltmeter connected to black wire and central earthing, with ignition turned on.   

 

10.6 

Oxygen sensor 

Signal voltage of oxygen 
sensor  

Close ignition, and connect socket connector of oxygen sensor. Connect voltmeter to black and 
grey cables of oxygen sensor. The engine is started and running at idling speed, and observe 
display of measuring instrument after several minutes.   

Display slowly between 
0.2…0.8V 

10.7 Oxygen 

sensor 

Close-cycle control of 
oxygen sensor, 
interference identification 
of signal voltage   

Same as Step 10.6. When swinging at display, take out vacuum hose with fuel regulator and 
seal it. After inspection, plug in hose at pressure regulator.   

Display stable within short 
time. Then re-swing.   

10.8 

Grey cable  

Cathode conductor signal 
connection  

Close ignition, take out controller plug, and disconnect socket connector of oxygen sensor, and 
connect multimeter/   

 

10.9 Oxygen 

sensor 

Black cable   

Anode conductor signal 
connection 

Same as Step 10.8; connect multimeter to black cable. After inspection, connect socket 
connector of oxygen sensor.   

 

11.1 Cooling 

liquid 

temperature 

sensor  

Supply voltage of cooling 
liquid temperature sensor

Close ignition, and turn on controller plug. Take out plug of cooling liquid temperature sensor. 
Connect voltmeter and turn on ignition.   

About 5V 

11.2 Cooling 

liquid 

temperature 

sensor 

Note: this value is related 
to temperature 

Same as Step 11.1, but connecting plug of cooling liquid temperature sensor.   

 

11.3 

Cooling liquid temperature 
sensor 

Connection between 
signal and controller 
conductor  

Close ignition, take out controller, and take out plug of cooling liquid temperature sensor. 
Connect the multimeter.   

<0.5Ω 

11.4 

Cooling liquid temperature 
sensor 

Connection between 
cathode conductor and 
controller conductor   

Same as Step 11.3, with multimeter connected to another terminal.   

<0.5Ω 

12.0   

AC ready and AC 
compressor input   

Close ignition, and take out controller plug. Open knife type panel of controller plug. Plug in 
controller, with voltmeter connected to the following terminals.   

 

12.1 

18...41 

AC ready to input   

The engine is started and running at idling speed. Close air conditioner.   

About 12V 

12.2 

18...41 

AC ready to input 

Same as step 12.1, but with air conditioner turned on.   

About 0V 

12.3 

18...40 

AC compressor input 

Same as step 12.1, with voltmeter connected to another terminal, and air conditioner closed    About 12V 

12.4 

18...40 

AC compressor input 

Same as step 12.3, but with air conditioner turned on. 

About 0V 

13.1 

Ignition coil 

Power supply from ignition 
coil (ignition switch) 

Close ignition, and take out controller plug. Connect voltmeter. Ignition turned on. 

About 12V 

 
 

 

126 

13.2 

1...2 

Ignition coil source input 

Same as Step 13.1, with voltmeter connected to another terminal.  

About 12V 

13.3  Ignition coil connecting 

conductor  

Power supply from ignition 
coil (with load) 

Close ignition, take out controller plug, and remove connecting conductor of ignition coil 
(ignition switch and terminal 1), and connect one load resistance to ignition switch and 
connecting conductor of terminal 1. Make bridge connection at controller plug (from 2 to 1. ) 

 

13.4 

B+… ignition coil   

Ignition coil voltage F drop 
(ignition switch) 

Same as Step 13.3. with voltmeter connected to B+ and ignition switch (load resistance).   

<0.5V 

13.5 

ECU terminal 1 
Ignition coil terminal 1 

Cathode conductor 
voltage drop of ignition coil

Same as Step 13.3. with voltmeter connected to controller terminal 1. 

<0.5V 

13.6 

 

Ignition coil 

Close ignition, and connect connecting conductor of ignition coil. Connect controller plug, and 
remove conductor of ignition coil, and connect proper lightening distance, which is adjusted to 
10mm. note: during inspection, do not hold or contact part 1 of ignition device with hands to 
operate the starter.   

Intense blue spark seen 
during lightening   

14.1  Ignition 

coil 

 

Closed angle, closed 
angle control   

Ignition “closed”, connect control plug. Connect conductor 4 of ignition coil. Turn on engine 
tester of ignition coil and adjust to closed angle for measurement. The engine is started and 
running at idling speed. Read out closed angle (measured value of the tester).   

 

14.2  Ignition 

coil 

Closed angle, closed 
angle selection   

Same as Step 14.1, but with rotating speed slowly increased to about 3000rpm.   

Display  value  becomes 
larger  

14.3 

Ignition coil 

Voltage drop of ignition 
final stage. Note: this 
measurement is only valid 
when using proper 
measuring instrument.   

Same as Step 14.1, with engine tester converted to dynamic voltage drop for measurement.     

14.4 

Ignition coil 

Voltage drop of ignition 
final stage. Note: this 
measurement is only valid 
when using proper 
measuring instrument. 

Same as 14.2, but with engine slowly increased to about 3000rpm.   

 

15.1  Ignition 

distributor 

 

Basic arrangement of 
distributor  

Ignition “closed”, take out plug of hall sensor. The engine is placed at top dead center of the 
first cylinder (not rotating at camshaft). Take out ignition distributor cover, and evaluate marking 
position of distributor rotor.   

For basic adjustment, mark 
on the distributor cover fit 
with distributor rotor center. 

15.2 

Ignition timing correction 
of distributor   

Distributor arrangement 

Ignition “closed”, connect plug of hall sensor, and install ignition distributor cover. optical disc 
lamp of tong sensor is connected to ignition conductor of the first cylinder.   
Note: when engine tester is with dead center sensor, tong sensor is not needed to connect. 
With the engine under hot running, temperature of cooling liquid is larger than 80 . Connect 

℃

the diagnosis instrument, and choose ignition correction function, and at this point idling speed 
could be increased to about 1500rpm. If with ignition correction line (terminal 51), it could be 
selected. Ignition correction line (terminal 51) is earthed.   

Ignition time 6.75° 
crankshaft angle (mark) 

15.4  Ignition conductor of 

induction thong (the first 
cylinder) or top dead 

Digital idling-speed 
stabilization function 

With the engine under hot running at idling speed, measure ignition advance angle. And 
connect electric instruments as much as possible, such as heating pad, high beam. And 
observe ignition mark or ignition angle display of engine tester.   

When electric instruments 
are turned on, adjust 
ignition timing quickly.   

 
 

 

127 

center sensor   

16.1 

 

Conductor connection of 
oil injector of the first 
cylinder  

Close ignition, and take out controller plug. Remove fuse of oil pump and heating element of 
oxygen sensor. Bridge connection with terminal 14, 3 and 46. Connect 2 (-) and 17 (+) with 
voltmeter.  

About 12V 

16.2 

 

Conductor connection of 
oil injector of the second 
cylinder 

Same as 16.1, with voltmeter connected to 2 (-) and 16 (+). 

About 12V 

16.3 

2...35 

Conductor connection of 
oil injector of the third 
cylinder 

Same as 16.1, connect 2 (1) and 35 (+) with voltmeter 

About 12V 

16.4 

2...34 

Conductor connection of 
oil injector of the fourth 
cylinder 

Same as 16.1, connect 2 (1) and 34 (+) with voltmeter 

About 12V 

17.1 

B+...+EVl 

Power supply under load

Close  ignition,  and  take  out  controller plug. Remove all plugs of oil injector. Connect load 
resistance to the first cylinder and terminal 14. voltmeter connects to positive connection of B+ 
and load resistance. Remove fuse of oil pump and heating element of oxygen sensor, with 2 
bridge connected to 3 and 46. 

＜

0.5V 

17.2 

B+...+EV2 

Power supply under load

Same  as  17.1,  switching  with another terminal for load resistance and voltmeter to positive 
conductor (connecting plug for cylinder oil injector at cable side) 

＜

0.5V 

17.3 

B+...+EV3 

Power supply under load

Same as above-mentioned, but for cylinder 3 

＜

0.5V 

17.4 

B+...+EV4 

Power supply under load

Same as above-mentioned, but for cylinder 4 

＜

0.5V 

19.5 EV4+... 

Startup 

control 

 

Note: this measuring 
instrument could be used 
at each oil injector. 

Close ignition, and switch on controller plug. Connect closed angle tester to oil injector of fourth 
cylinder with switching conductor. Remove fuse of oil pump. Remove conductor of ignition coil 
(ignition switch). Remove plug of cooling liquid temperature sensor and connect one resistance 
with 30 thousand ohm to replace NTC. Operate starter for about 15 seconds, and observe 
display of closed angle tester. Display when startup:   
Display after startup for about 5 seconds:   
Display after startup for about 10 seconds:   
 

25...35％ 
10...20％ 
5…8％     

20.1 

4...26   

Internal  resistance  of 
stepper motor   

Close ignition, take out controller plug, and connect the multimeter. Note: resistance is related 
to temperature.   

35…95 ohm 

20.2  21...29 

Internal resistance of 
stepper motor coil   

Close ignition, take out controller plug, and connect the multimeter. Note: resistance is related 
to temperature. 

35…95 ohm 

20.3 

4… stepper motor 
terminal B 

Conductor connection   

Same as 20.1, take out plug of stepper motor, with the multimeter switched to corresponding 
terminal.  

＜

0.3ohm 

20.4 

26… stepper motor 
terminal C 

Conductor connection 

Same as 20.1, take out plug of stepper motor, with the multimeter switched to corresponding 
terminal. 

＜

0.3ohm 

20.5 

21… stepper motor 

Conductor connection 

Same as 20.1, take out plug of stepper motor, with the multimeter switched to corresponding  ＜0.3ohm 

 
 

 

128 

terminal D 

terminal. 

20.6 

29… stepper motor 
terminal A 

Conductor connection 

Same as 20.1, take out plug of stepper motor, with the multimeter switched to corresponding 
terminal. 

＜

0.3ohm 

20.7 

Stepper motor 

Control   

Close ignition, turn on controller plug and turn on speed counter. Connect the tester to stepper 
motor with switching conductor. The engine is started and running at idling speed. Display on 
the speed counter:   
Display on the closed angle tester:   

About  
850rpm 
60…80 step 

20.8  Stepper 

motor 

Idling speed governing 
function  

Same as 20.7, electric instruments such as heating pad shall be exact and turned on at the 
same time. In case of servo steering, rotate to stopper and stop when the vehicle is at rest. 
Observe display on the speed counter and closed angle tester.   

Rotating speed quickly 
reduced under the load, 
then increased to starting 
value 

20.9 

Stepper motor 

Basic governing of idling 
speed 

Same as 20.7, the engine is still warm, and close all current consumption instruments. Connect 
diagnosis instrument and choose basic governing function. Choose maintenance connector 
terminal. and make terminal 39 (controller) earthed. Observe display on the speed counter and 
closed angle tester. Adjust bypass bolt. Running at idling speed.   

Adjusted value   

21.1 51... 

Connection  between 
ignition correction 
conductor to controller 
(terminal 51) conductor   

Close ignition, take out controller plug and connect the multimeter.   

＜

0.5ohm 

22.1 

55... 

Connection between fuel 
conductor to controller 
(terminal 55) conductor 

Close ignition, take out controller plug and connect the multimeter. 

＜

0.50ohm 

23.1 

3...2   

Fuel pump relay control, 
final stage   

Ignition “closed”, take out controller plug. Take out casing of controller plug, and turn on 
controller plug, with voltmeter connected to terminal 1 and 2. “ignition” turned on, and starter 
not started.   

About 12V 

23.2 

3...2 

Fuel pump relay control, 
driver stage 

Same as 23.1, but engine started and running at idling speed. 0.5...2.0V