HDK Service Manual

31

Malfunctions

0

⑴ Push the horn switch and will not respond

Wrong or bad connection of horn, check the horn plugs, use a multimeter to check whether where is voltage loaded on horn when push the switch. If all is right. Then the horn is bad

⑵ Strange horn voice

Push the horn, change the contact position of the horn and frame. Clean the surface of the horn especially dirt on it .

⑶ Horn have sound on when push the switch but go off after

Crank the tightness of the horn, use a screwdriver to rotate the middle screw to change the tightness of the horn .

RELAY

Relay is as a electric switch in the circuit system, the relay is be placed in input side of the DC-DC convertor as electric switch to control the converter power supply, when vehicle power is turned on the relay will click on, when the power is turned off the relay will brake attach.

①

Relay malfunctions

⑴ Power switch is on, relay no respond .

Check the connection see whether it is good connection condition, if it is then the Relay is bad.

①

②

③

● ●

FUSES

For protect the electronic circuit, fuses are required. The vehicle circuitry’s property is low voltage and high current. In case of short circuit, over current working, fuses are placed in the circuit for secure the electronic components, in case default operation may cause unrepairable damages.

① Main fuse for 1243/1246 system.

② Main fuse for 1268 system.

③ DC converter Input protective fuse for 1243/1246 system.

④ DC converter Input protective fuse for 1268 system.

Relay malfunctions

④

When the vehicle have a break down, turn on the power and whole circuitry system has no respond, then the main fuse should be checked, when the power is on and vehicle can be operated, but all lights and horn cannot be switched on. Then the DC converter Input protective fuse should be checked.

To judge a broken main fuse one can judge by physical eye observation, one can tell from the revealed fuse in the middle of the fuse, if it is broken then the fuse will be broken in the middle physically. For other fuses one can use a multimeter to judge, the resistance of the fuses are zero, if it is broken means the inner connection be disconnected.

⑥

● ●

⑤

WHEN COMMIT THE FUSE CHANGING, THE POWER SHOULD

BE TURNED OFF.