BYD EPS14P, Operator'S Manual

MAINTENANCE

OPERATOR MANUAL

70

EPS14P

71

OM-EPS14P2019001-EN

Display

ALARM

Fault name

Recommended inspection

06A19

KM OPEN

Main contactor of slave 

contactor open

Slave contactor monitors the open of safety contactor of main contactor, and the 

controller needs to be replaced;

06A20

MAIN CONT.OPEN

Main contactor open

The coil of main contactor has been energized by the logic card, but the contactor 

does not engage. Possible cause:

1.The contactor has mechanically become faulty, or its contacts get stuck

2.The contacts of contactor cannot make securely

3.If the contactor operates normally, replace the controller.

06A21

MICRO SLAVE

The information on the 

status bus between the 

main microprocessor and 

slave microprocessor is 

frozen to the OXFF value.

The controller should be replaced;

06A22

S.P OUT OF RANGE Output steering poten-

tiometer out of range

If a single potentiometer, such as CPOC1 end, is out of range 0.8V-4.2V, it will 

alarm. When the dual potentiometer is selected, the sum of the two sliding ends 

(CPOC1+CPOC2) is out of the range of 4.4V-5.5V and it will alarm. Check the 

connection of potentiometer.

06A23

F.B OUT OF RANGE Feedback of steering motor 

encoder out of range

Feedback potentiometer (CPOT connecting to CNB#6) has fault, it will alarm. The 

range of CPOT is out of 0.3V-4.7V, it will alarm. Check if the steering motor encoder is 

connected correctly and whether there is a open circuit;

06A24

MICRO SLAVE KO

M a i n   a n d   s l a ve   m i c ro -

processor detection does 

not match

1.When using a stepper motor, the direction of the stepper motor detected by the 

main microprocessor and slave microprocessor is inconsistent;

2.In the closed-loop control system, the direction of the stepper motor detected by the 

main contactor is incorrect and is inconsistent with the direction of the stepper motor 

detected by the slave contactor;

3.The main contactor did not detect the steering limit position, but it was detected by 

the slave contactor;

06A25

ENCODER ERROR

Encoder fault

The controller detects that two successive speed readings of the encoder differs 

greatly from each other. A normal encoder in the system cannot change speed 

readings greatly within a very short time. Hence, a possible cause for the symptom is 

that the wires of one or more encoders are worn or broken. Check the mechanical and 

electrical parts of the encoder. Another possible for the symptom is electromagnetic 

interference from the sensor bearing. If the symptom is not due to the two causes, 

replace the controller.

Note: Sometimes manual operations may also cause this fault indicating on the 

controller. In these cases, it is required to turn off power supply and start the forklift 

again. For example:

1.The forklift suddenly collides with an obstacle so that it is incapable of travelling;

2.The driver applies the brake sharply while the forklift is travelling at a high speed

06A26

BAD ENCODER SIGN Encoder phase sequence 

error

Change encoder A, B phase;

06A27

GAIN EEPROM KO

EEPROM memory current 

value is different

Replace the controller;

06A28

CAN BUS KO

CAN BUS communica-tion 

fault

1.Check if the CAN BUS communication line is connected properly;

2.Check if the bit rate of the communication is consistent;

3.Check if the CAN communication is open;

4.Check if the CAN communication loop resistance is 60Ω.

06A38

POSITION ERROR

Position error

1.Check if the steering motor encoder A and B phases are loosely connected;

2.Check if the steering motor A and B phases receive interference;

06A39

SERIAL ERROR #1

Slave contactor does not 

receive the information of 

main contactor from  serial 

port

Replace the controller;

06A40

MICRO SLAVE #4

Steering motor current is 

opposite to the command 

direction

Replace the controller;

06A41

SLAVE COM. ERROR

Main contactor does not 

receive the information of 

slave contactor from  serial 

port

Replace the controller;

06A43

CURRENT GAIN

Controller maximum current 

is not controlled

Replace the controller;

06A44

CLOCK PAL NOT OK Clock error

Replace the controller;

06A45

STEER SENSOR KO

Dual potentiometer fault

Check the wiring and output of the two-way steering potentiometer.

06A46

JERKING FB

Steering potentiometer 

voltage changes too much

Replace the feedback potentiometer;

06A47

FB POT LOCKED

Feedback value of steering 

poten-tiometer locked

1.Check if the feedback steering potentiometer has mechanical looseness;

2.Check if there is a mechanical limit;

3.Check if the feedback steering potentiometer reaches its own limit point;

4.If the fault occurs in the opposite direction of the steering wheel during installation, 

adjust the direction of the steering wheel;

06A48

MOTOR TEMPERAT. Motor temperature high

1.If the motor temperature digital switch is turned on, or analogue signal exceeds 

the cutout value, then the fault results.2.When motor temperature rises to 120° C, the 

controller will display the warning. The forklift still can travel but the maximum current 

is reduced with the forklift performance degraded. When the motor temperature 

reaches 125° C, the motor stops working. In this case, action shall be taken to cool the 

motor.3.The fault still exists when the motor cools, check the line. If all have no faults, 

replace the controller.

Display

ALARM

Fault name

Recommended inspection

06A49

MOTOR LOCKED

Steering motor stalling

Steering motor continuous maximum current time exceeds 1s;

06A50

STEPPER MOT MISM Frequency of stepper motor Q and D 

line and voltage values do not match

Replace the controller;

06A52

MICRO SLAVE #8

The encoder of the main micropro-

cessor is inconsistent with the encoder 

of the slave microprocessor

Replace the controller;

06A53

INPUT ERROR #1

Advanced steering controller CAN#4 

has a voltage input higher than 12V

Check if the CAN#4 cable is correct;

06A54

CAN BUS KO SL.

Slave contactor does not receive any 

CAN information from main con-

tactor

Replace the controller;

06A55

SL EPS NOT ALL.

Self centering is not completed

Replace the controller;

06A56

SL CENTERING

Swing angle of self centering is out of 

range

Replace the controller;

16A06

Communication fault

Check the CAN cables of control handle, instrument panel, and steering 

controller

17A01

battery high temp.

waring

Battery high temperature warning

17A02

battery high temp. 

alarm

Battery high temperature alarm

17A03

b a t t e r y   l e a k a g e 

waring

Battery leakage warning

17A04

b a t t e r y   l e a k a g e 

serious

Battery leakage alarm

17A05

battery Status Alarm Battery status alarm

17A06

BDI low

Battery level low (SOC ≤ 10%)

17A07

BDI low

Cell voltage too low, general warn-ing

17A08

BDI low

Cell voltage too low, severe warning