troubleshooting

7.15.8.29 The pilot lamp of hydraulic-brake fluid low level in the tanks of brake control system activates on the pilot lamps unit HG1 when the system is filled up. ) Check sensor operability of hydraulic-brake fluid SL1 level for which it is required to remove the socket from the sensor. If the lamp goes out – replace the sensor. If the lamp does not go out, check the circuit operability in the system sensor – pilot lamp PLU HG1 for presence of locking on tractor body. If the circuit is short cut – eliminate the failure.

b) If the sensor SL1 and the electrical circuit sensor SL1– pilot lamp PLU HG1 operate properly (there is no locking) – replace the pilot lamps unit. 7.15.8.30 The pilot lamp of heating plugs operation signaling in the pilot lamps unit HG1 does not operate while heating plugs operate normally. Lock the contact of HP pilot lamp activation in PLU for tractor “load” by means of a bonding strip for a short period. In case the lamp does not activate, check supply voltage availability of PLU. If there is no supply voltage – replace the PLU. If there is no supply voltage, eliminate the circuit breakage from fuse block F5 to the PLU.

7.16 Possible failures of air-conditioning and cab heating systems and guidelines for troubleshooting

List of possible failures of air-conditioning and cab heating systems and guidelines for troubleshooting are shown in Tables 7.16 and 7.16b. Table 7.16b – Possible failures of air-conditioning and cab heating systems and guidelines for troubleshooting

Failure, external manifestations, cause Troubleshooting

Warm air is not supplied into the cab

Coolant is not circulated through heating unit: - turn over heater control valve - heater fan is out of operation Open heater control valve Correct fan trouble, check electric circuit of fan switching on according to electrics diagram in Annex B.

Warm air of high humidity is supplied into the cab

Leakage of coolant in heating radiator Stop leakage or replace heating radiator Leakage of coolant in heating system connection Tighten up coupling bands

WARNING: DURING TRACTOR DISCONNECTION CLOSED-CIRCUIT AIR CONDITIONING SYSTEM MAY BE DETACHED BY MEANS OF SEPARATION OF QUICK DISCONNECT COUPLER. DISCONNECTION SHOULD BE PERFORMED BY UNSCREWING OF CAP NUT “B” (FIGURE 7.16.1) (WITH HEXAGON SCREW KEY SIZE 30MM) FROM VALVE "A" (WITH HEXAGON SCREW KEY SIZE 29 MM)! WHILE CONNECTING THE DUCT IT IS NECESSARY TO PUT SILICONE SEALANT ON THE THREAD. AFTER THREE OR FIVE DISCONNECTIONS A LEAKAGE CAN OCCUR IN JUNCTION POINT – REPLACE IT IN THIS CASE!

WARNING: WHILE DISCONNECTION AND CONNECTION OF DUCTS WEAR PROTECTIVE GLOVES AND GLASSES!

WARNING: ANY OPERATIONS RELATED TO DISCONNECTION OF AIR CONDITIONING SYSTEM COMPONENTS SHOULD BE CARRIED OUT ONLY BY TRAINED PERSONNEL WITH USE OF SPECIAL EQUIPMENTS FOR AIR CONDITIONING SYSTEM MAINTENANCE. HIGH PRESSURE IS MAINTAINED EVEN IN SHUT DOWN SYSTEM!

WARNING: COOLING AGENT R134A NON TOXIC, NON COMBUSTIBLE, NOT FORMING EXPLOSIVE MIXTURES. COOLING AGENT BOILING TEMPERATURES IN NORMAL CONDITIONS IS MINUS 27 . IN CASE OF SKIN CONTACT WITH LIQUID COOLING AGENT, IT FLASHES AND CAN CAUSE OVERCOOLING OF SKIN AREAS! WARNING: ONLY SPECIALLY TRAINED PERSONNEL IS ALLOWED TO PERFORM REPAIR AND MAINTENANCE SERVICES OF SYSTEM COMPONENTS!

Table 7.16b – Possible failures of air-conditioning and guidelines for troubleshooting

Failure, external manifestations, cause Troubleshooting

Compressor electromagnetic coupling will not respond (no metallic click while turning temperature regulator)

Electric equipment failure By means of tester or multimeter check operability of pressure sensors unit, sensors unit outputs (red and pink wires) should be “rung out" among themselves. Check up operability of electric circuits connections from compressor coupling to air conditioner control console according to the electrical equipment diagram in Annex B Coolant leakage took place Detect leak path. Only specially trained personnel is allowed to detection of leak path, replacement of hoses and air conditioner components with use of special equipment (after-sales service and repair should be carried out by CJSC “Belvneshinvest”, Minsk, tel./fax 8-017-262-40-75, 8-029-662-97-69, 8-029-628-6798)

Nonoperable conditioner fan electric motor

Electric equipment failure Check up operability of the corresponding fuse element located in the switching unit. Replace if it is faulty. If the safety lock is properly operating check by means of indicating lamp power supply presence on the electric motor of air conditioner fan ( 2, Annex B) when the switch is on and "ground" is available in electric motor. If electric circuits are properly operating, but there is lack of power supply to 2, replace the switch.

When air conditioner operated in cooling mode warm air is supplied into

cab

Valve PO-11 seal element breakage Replace valve PO-11

Coolant leakage from cab ventilation compartment

Disruption of heating unit tubes (heating unit “defrosting” due to incomplete drain during cool weather period operation) Replace conditioner climatic unit

Figure 7.16.1 – Quick disconnect couplers kit