A bus is equipped with ZF Ecolife 6AP1400B hydraulic automatic transmission of the large channel bus, repair workshop feedback operation sometimes the gearbox in a stall, unable to lift the gear;

1. Telephone guide bus to check the gearbox fault code and routine signal inspection using client version of Testman;

The Ecu has gearbox high temperature alarm failure code;

After deleting the code, high temperature alarm code still appears;

The transmission oil temperature exceeds the water temperature;

2. Advise the customer to send the transmission to ZFDS for overhaul and maintenance;

3. After the inspection, the following problems are found:

Open the refueling cover and have the pungent smell of oil.

After the inspection, it was found that all the friction pieces of B and F were burnt, and the friction layer fell off, especially the friction plate of group B had been bitten to the teeth.

Partial sealing ring hardening;

After further decomposition of all components, the fixed screw of the planetary frame bearing seat was found to be almost completely deformed.

Screw hole deformation, output speed signal wheel fixed screw off;

After the outer ring of the bearing seat of the shell body is worn out, and the solar axle is worn;

F piston is damaged;

conclusion

1, from the view of friction plate burning, the gearbox early already exists the phenomenon of shift up slow, the driver did not observe, to continue to run in spite of, high temperature lead to the gearbox, further damage of friction plate;

2. From the distortion of the screw hole, the output end abnormal jitter causes the screw hole deformation and disengagement;

3. After communicating with the public transport, the transmission shaft jitter caused damage to the radiator