HYSTER Forklift Truck Error Codes

A HYSTER Forklift Trucks Fault Codes DTC list

 

- AL01

- Condition: traction and hoist functions not working

- Cause: incomplete connection between control card and controller; traction reversing switch not connected; damaged or defective tiller card

- Solution: check connections between control card and controller; use a handset to test for operation of traction reversing switch; replace control card if tiller card is damaged

 

- AL02

- Condition: traction and hydraulic functions not working

- Cause: main contactor tips are welded closed or motor field circuit is broken

- Solution: disconnect power leads at contactor and test for an open circuit; check connections between motor field and controller

 

- AL4

- Condition: traction and hydraulic functions not working

- Cause: damaged connection to lowering valve; damaged lowering coil or lowering valve cartridge

- Solution: check electrical connection between valve coil and controller; check lowering valve coil for resistance, replace if not approximately 17.7 ohms; replace lowering valve cartridge if necessary

- AL5

- Condition: traction and hydraulic functions not working

- Cause: damaged connection to brake or brake coil damaged

- Solution: check connection between electric brake and controller; check brake coil for resistance in both directions and replace if not between 27.36 and 30.24 ohms

 

- AL6

- Condition: traction and hydraulic functions not working

- Cause: damaged connection to traction motor; traction motor armature resistance is too low; field wires are loose or damaged; motor field winding is shorted or too low

- Solution: check electrical connection between traction motor, field wires, and controller; check traction motor armature for shorts; check motor field resistance and correct if not between 0.5 and 1.5 ohms; check contactor coil for resistance of 52 ohms

 

- AL7

- Condition: traction functions reduced below 14°F or above 167°F and not working above 194°F

- Cause: controller temperature is too hot or cold; controller temperature is not calibrated correctly; controller sensor or controller itself is damaged

- Solution: move truck to a warmer or cooler location; use a handset to check that controller temperature matches room temperature (if not, replace controller)

 

- AL8

- Condition: traction and hydraulic functions not working

- Cause: over current in driven component

- Solution: check main harness for damaged connections to main contactor, brake, and electric valve coils; check contactor, brake

- AL66

- Condition: hydraulic function not working

- Cause: battery voltage is low or controller voltage calibration is incorrect

- Solution: charge or replace battery; otherwise, use handset to determine the voltage read by the controller and compare it to an actual voltmeter reading; replace controller if the two readings differ by more than 1.5 volts

 

- AL99

- Condition: traction and hydraulic functions not working

- Cause: incorrect battery selected, damaged battery, or damaged connection to batter

- Solution: check that you have the right voltage for your truck, manually check the voltage of your battery, inspect it for any damage, and check its connecting crimps and cables for damage as well

 

- no LEDs or LCDs on

- Condition: inoperative

- Cause: B+ and/or B- missing at controller, defective battery charger, or defective battery charger

- Solution: make sure battery is connected, the key switch is on, and the brake override circuit is in the run position; also test your battery charger and motor controller and replace any nonworking parts

 

- no LEDs or LCDs on

- Condition: forklift functions as normal

- Cause:  open connection between display and controller, defective display, or defective LEDs

- Solution: make sure harnesses are connected at MDI and connector B on controller; test the dash display by connecting a handset to it and testing for communication; test LEDs by disconnecting them, connecting the handset, and testing the handset; replace any nonworking parts

 

- no LEDs or LCDs on

- Condition: forklift functions as normal

- Cause:  Because this condition is similar to the last, it will take a handset to determine its cause. If the handset displays “NO COMMUNICATION,” the controller is defective.

- Solution: replace controller

 

- no alarm

- Condition:  traction and hydraulic functions not working

- Cause: improper startup sequence by jack operator

- Solution: check brake switch, accelerator, steer handle, and hydraulic inputs