Diagnosis of the first failure can be measured. Application of gauges and instruments in accordance with national standards for car parts and various parameters of the effective measure of fault diagnosis and debugging is an indispensable method. Do not overlook the use of launch x431.Measure the length of use to the meter stick, and the length of the measure, including diameter, gap and displacement measurement to use to micrometer, micrometers, plug, plug ruler, tape measure, etc.; force and gravity measurements to use to measure force meter, and weighing devices, etc.; pressure and vacuum measurement use to gauge and vacuum table, etc.. Automotive measuring instruments also have a variety of measurement units, such as use for the measurement of sound pressure sound pressure level of dB values; for voltage measurement to the underlying value of such use.
For the steering system failure, use the instrument and the front wheel before the beam measured value of the steering wheels and so on before the beam; use the tire pressure gauge tire pressure measurement; point scale the amount available when necessary the rotation of the steering wheel to the exact determine cause of the malfunction. For the engine failure, to measure the cylinder in the engine cylinder after the dissolution of the diameter, measured piston diameter, thickness and open space, etc., to identify the exact cause of the failure to repair the engine; is to repair to re-measurement of the cylinder tube diameter, and in accordance with the requirements of groups, matching the piston and piston rings in order to fix the engine.
Diagnosis of electronic control system failure, even more indispensable measure, such as unstable or power of the lower engine work, the suspected oil pressure is insufficient, we must use the pressure gauge pressure measurement system; suspected electrical control system electronic control problems, necessary to use digital multimeter measuring voltage and resistance; with frequency counter and oscilloscope measurements such as frequency and amplitude. Hence a variety of measurement instruments and scales are maintenance personnel extension of eyes and hands, only to accurately determine the correct measure, while the seat of your pants is just the surface, the measurement method and instrumentation method combining the use of more measurement devices should be more accurate diagnosis.
Can also be sub-test for diagnosis of faults. lexia3 on solving problems is very effect. The so-called sub-checking method is the car mechanics of the motor vehicles on the line, with the system piping and check the nature of the fault line of work, inspections will be in accordance with the system starting from the power source system to the enforcement agencies along the route lookup is also available after to pre-order search, you can find from the middle, depending on the experience of the examiner. If suddenly from the implementing agencies to find a good course, or have to return back to previous search.
For example, and instructions for lighting system failure, the principle should be power on – switch – fuse – Relay – wire – light bulb line, front to back beginning to find that experience can first check the fuse, some people might first check light bulbs, there is people may first check relay, when the front to back or forward, finding out may occur in the middle of the problem may be bad combination switch, there may be broken wire somewhere.
The brake system failure, the principle on the brake pedal should be – vacuum boosters – brake master cylinder – Brake Lines – load sensing valve – brake pipe – wheel brakes in order to be checked. For experience you can from the wheel brake or brake master cylinder started checking, and then check the other part; but difficult for the brake system failure, it should be after the use of measuring instruments used to to check and measure. To find the cause of the malfunction.
The steering drive system failure, the principle on the steering wheel should be – Steering – Steering gear – steering wheel of the order of inspection. For convenience, you can shift gears from somewhere open, easier to determine fault in the steering gear or transmission of the rear part. Use of the existing theoretical knowledge, with the sub-test for orderly conduct of inspection, will eventually find the root causes of failure.
Partial disassembly method can also diagnose faults..Called partial disassembly method, that is, car mechanics Yijing identify a fault in the assembly Mouge After it, a time not Zhunquepanduan which half of the failures occurred, they can in accordance with the assembly of the working principle of the demolition of a local Bufen function check, and then put something in the method. If the method used properly, can immediately determine the site of fault, therefore, be regarded as a simple partial disassembly method of rapid diagnosis of vehicle faults.Partial disassembly method and test method has many similarities, the difference is mainly local demolition method to demolition, dismantling and try again in a diagnostic faults.
For example, a suspected engine cylinder is not working, single-cylinder off oil removal method can be used to check, remove the partial demolition of a high pressure pipe fittings cylinder engine running in both speed and sound change is that the tank is working properly; without reflecting is not working properly.Some of the best major to diagnostic techniques, such as mb star.Lack of engine power when the suspect blocked air filter, you can try removing the air filter core engine, such as the power of the air filter case without recovery, fault here.
Partial disassembly method is actually to work the engine or the electric loss of the original function, while movements in non-normal conditions, it must be careful disassembly, when it comes to security projects to take appropriate safety measures. Better technology has launch x431, lexia3, mb star. All the fault diagnosis methods are complementary, the purpose is to find the car the fault occurred. Flexible use of fault diagnosis, fault can find cars, targeted on the cars and engines maintenance, restoration of normal use function.