Road test (road test)
Before road testing, ensure that basic checks have been completed, including checking the level and condition of the CVT fluid and adjusting the CVT control cable.
1. Turn the ignition key from position "OFF" (OFF) into position "ON" (ON) and check the operation of the variator control relay (presence of voltage).
2. When the ignition key is in the "ON" (ON) and the engine is not running do the following:
- A) (Models with manual shift mode) Move the variator selector to the positions "R", "N", "D", "Ds". Check the operation of the start inhibit switch (correspondence of the position of the selector and the signal of the switch).
- b) (Models without manual shift mode) Move the variator selector to the positions "R", "N", "D", "Ds", "L". Check the operation of the start inhibit switch (correspondence of the position of the selector and the signal of the switch).
- V) Move the variator selector to position "D" and check that the manual mode select switch is in the "OFF" (OFF), upshift switch (UP) pregnant "OFF" (OFF), downshift switch (DOWN) pregnant "OFF" (OFF).
- G) Move the CVT selector to the position corresponding to the manual shift mode and check that the manual mode selector switch is in the position "ON" (OFF), upshift switch (UP) pregnant "OFF" (OFF), downshift switch (DOWN) pregnant "OFF" (OFF).
- d) Move the CVT selector to the manual upshift position and check that the manual mode selector switch is in position "ON" (OFF), upshift switch (UP) pregnant "ON" (ON), downshift switch (DOWN) pregnant "OFF" (OFF).
- e) Move the CVT selector to the manual upshift position and check that the manual mode selector switch is in position "ON" (OFF), upshift switch (UP) pregnant "OFF" (OFF), downshift switch (DOWN) pregnant "ON" (ON).
3. When the ignition key is in the "ON" (ON), the engine is not running and the variator selector is in position "R" do the following:
Check the throttle position sensor:
- - When the accelerator pedal is released (900 - 1100 mV).
- - When pressed half way (smoothly increases from the value of 900 mV).
- - When the accelerator pedal is fully depressed (4000 mV).
4. Move the variator selector to position "R" or "N". Set the ignition key to position "START" (START) (engine not running) and make sure the engine start (crankshaft cranking by starter) only possible in the specified selector positions.
5. Drive the vehicle for 15 minutes or more, and check the operation of the CVT fluid temperature sensor (the temperature of the working fluid of the variator gradually increases to 45-100°C).
6. When the engine is idling and the CVT selector is in the "R" perform the following checks:
Check the nominal values with the accelerator pedal not depressed:
- - Frequency of rotation of a cranked shaft: 600 - 800 rpm.
- - Turbine shaft speed: 600 - 800 rpm.
- - Main line pressure (according to the readings of the pressure sensor in the main line): 0.6-1.5 MPa.
- - CVT fluid pressure (according to the readings of the variator working fluid sensor): 0-0.6 MPa.
- - Gear ratio: 2.313.
- - Main line pressure control solenoid valve: 70 - 90%.
7. With the engine idling, perform the following checks:
- A) When translating the variator selector from the position "N" V "D" and from "N"
- V) "R" make sure that there are no malfunctions at the beginning of the movement (there should be no sudden shocks when shifting gear, the gear engagement time should not exceed 2 seconds).
- b) When translating the variator selector from the position "N" V "D" and from "N" V "R" make sure the pressure control solenoid valve is working (torque converter lock-up clutch): 100% -> 0%.
- V) When translating the variator selector from the position "N" V "D" check torque converter lock-up clutch (revolutions: less than 2040 rpm).
8. Perform checks when the variator selector is in position "D":
- A) The car is stationary (torque converter clutch solenoid valve - 0%) - the car moves on a flat horizontal surface at a speed of no more than 50 km / h (torque converter clutch solenoid valve - 35%).
- b) When driving on a flat horizontal surface at a speed of 50 km/h or less, check the torque converter lock-up clutch (revolutions: less than 40 rpm).
- V) Check the shift control solenoid valve: when the variator selector is moved from the position "D" V "Ds", during movement, the fill factor decreases, and when transferred from the position "Ds" V "D" the fill factor increases.
CVT operation diagram without manual gear change mode for sedan models from 05.2001 with 4G15-GDI engine).
CVT operation diagram without manual shift mode (sedan models from 05.2001 with 4G93-MPI engine).
The diagram of the operation of the variator with the mode of manual gear shifting.
Checking the torque converter on a fully braked vehicle (stall test)
Scheme of the variator. 1 - reverse brake, 2 - forward clutch.
The purpose of this test is to measure the maximum engine speed with the CVT output shaft fully braked on the ranges "D" And "R". By the value of its value, it is possible to determine the performance of the overrunning clutch of the torque converter stator and check the presence of slip in the friction elements - clutches and brakes.
Note:
- - Do not allow anyone in front of or behind the vehicle during this check.
- - The duration of each check should not exceed five seconds.
- - The test should be carried out by two technicians: one should observe the wheels outside the vehicle, and the second should carry out the test itself inside the vehicle.
1. Measurement of revolutions on a fully braked car:
- A) Check the level and temperature of the working fluid in the variator, as well as the temperature of the engine coolant. The working fluid in the variator must be warmed up to normal operating temperature (70-90°C). The fluid level must be in the range "NOT" probe. The engine coolant must also be warmed up to normal operating temperature (80-100°C).
- b) Place chocks under the rear wheels of the vehicle.
- V) Apply the parking brake and depress the brake pedal all the way.
- G) Start the engine.
- d) Move the selector to position "D". Press the accelerator pedal all the way. Take a quick reading of the tachometer and compare it with the nominal values.
Attention:
- During this test, do not hold the accelerator pedal fully depressed for longer than necessary to determine the maximum engine speed, or for more than eight seconds. - If this test needs to be carried out more than once, then after each test, move the variator selector to the position "N" and let the engine run at 1000 rpm to cool the working fluid in the variator between checks.
Nominal value of the engine speed when the vehicle is fully braked (selector in position "D"):
- models with 4G15 engine - 2100 - 2600 rpm
- models with 4G93 engine - 2200 - 2700 rpm
e) Repeat the test with the selector position in the range "R".
The nominal value of the engine speed when the vehicle is fully braked. (selector in position "R"):
- models with 4G15 engine - 1800-2300 rpm
- models with 4G93 engine - 1800-2300 rpm
2. Analysis of the test results on a fully braked vehicle.
A) If the engine speed is greater than the nominal value when the selector is in the position "D" or "R", the reason could be:
- malfunction of the solenoid valve block;
- faulty wiring or connector;
- malfunction of the electronic control unit for the engine and variator.
b) If the engine speed is greater than the rated value when the selector position "D", the reason could be:
- forward clutch slippage.
V) If the engine speed is less than the nominal value when the selector is in the position "R", the reason could be:
- reverse brake slip.
G) If the engine speed is less than the nominal value when the selector is in the position "D" or "R", the reason could be:
- - malfunction of the hydrotransformer;
- - malfunction of the electronic engine control unit.
Checking the pressure in the hydraulic control system of the variator (hydraulic test)
Note: checking the pressure in the variator control hydraulic system is the main one for determining the causes of the variator failure. Perform basic checks and adjustments before carrying out (check the level of the working fluid in the variator and its condition, etc.). Checking the pressure in the hydraulic system should be carried out at normal temperature of the working fluid of the variator (70 - 80 °C).
1. Checking the pressure in the lines:
- A) Warm up the variator fluid to operating temperature (70 - 80°C).
- b) Place chocks under the rear wheels of the vehicle.
- V) Apply the parking brake and depress the brake pedal all the way.
- G) Start the engine.
- d) Connect the adapter to the appropriate hole, connect the pipes and pressure gauge.
Note: when checking the pressure, use a pressure gauge with a measurement limit of 3000 kPa.
- e) Verify that the data obtained corresponds to the nominal values (see table "Checking the nominal pressures in the hydraulic control system of the variator").
Table. Checking the nominal pressures in the hydraulic control system of the variator.
Note: - Models without manual shift mode.
Note: CVT fluid pressure and main line pressure are for reference only.
2. Analysis of the results of checking the pressure in the hydraulic control system of the variator.
A) High pressure in all lines can be caused by:
- pressure measurement error.
b) Low pressure in all lines can be caused by:
- - malfunction of the working fluid pump;
- - malfunction of the working fluid filter;
- - malfunction of the working fluid cooler;
- - malfunction of the solenoid valve;
- - improper installation of the solenoid valve block.
V) Inconsistent with technical data pressure in the forward clutch line (FWD) can be caused:
- - a malfunction of the solenoid valve for manual gear shifting;
- - malfunction of the pressure control valve (torque converter lock-up clutch);
- - malfunction of the pressure control solenoid valve (RED) torque converter lockup clutches;
- - malfunction of the pressure control solenoid valve (torque converter lock-up clutch);
- - clogging of the highway;
- - improper installation of the solenoid valve block.
G) Inconsistent with technical data pressure in the reverse brake line (REV) can be caused:
- - a malfunction of the solenoid valve for manual gear shifting;
- - malfunction of the pressure control valve (torque converter lock-up clutch);
- - malfunction of the pressure control solenoid valve (RED) torque converter lockup clutches;
- - malfunction of the pressure control solenoid valve (torque converter lock-up clutch);
- - clogging of the highway;
- - improper installation of the solenoid valve block.
d) Out of specification pressure (RED) can be caused:
- - malfunction of the pressure control solenoid valve (RED);
- - clogging of the highway;
- - improper installation of the solenoid valve block.
e) Pressure in the main line that does not comply with the technical data can be caused by:
- - clogging of the highway;
- - malfunction of the pressure control solenoid valve (RED);
- - improper installation of the solenoid valve block.
and) Torque converter outlet pressure out of specification (DR) can be caused:
- - malfunction of the torque converter clutch control valve;
- - a malfunction of the solenoid valve for controlling the torque converter lock-up clutch;
- - malfunction of the pressure control valve in the torque converter;
- - clogging of the highway;
- - improper installation of the solenoid valve block;
- - Malfunction of the hydrotransformer.
h) An increase in pressure in a failed element can be caused by:
- - a malfunction of the solenoid valve for controlling the torque converter lock-up clutch;
- - a malfunction of the solenoid valve for manual gear shifting;
- - improper installation of the solenoid valve block.