Daewoo forklifts fault codes list

By |

Daewoo forklifts fault codes list

See also: Daewoo PDF Service Manuals

Daewoo G15S-2 Fault codes

Daewoo G15S-2

On this page, you can find definition of fault codes for such Daewoo forklifts as:

  • G15S-2 G18S-2 G20SC-2 Plus GC15S-2 GC18S-2 GC20SC-2 Plus;
  • GC20E-3 GC25E-3 GC30E-3 GC32E-3 Plus G20E-3 G25E-3 G30E-3 G32E-3 Plus GC20P-3 GC25P-3 GC30P-3 GC32P-3 Plus;
  • G20P-3 G25P-3 G30P-3 G32P-3 G33P-3 Plus G35S-2 G40S-2 G45S-2 G50SC-2 Plus;
  • G50S-2 G60S-2 G70S-2 Plus;

Applicable Daewoo serial number prefixes: FQ, FR, FY, G2, G3, G4, G5, G6, G9, GA, GB, GH, GQ. These trucks say “Plus” on the side near the model number.


The Check Engine light, found on the steering column dashboard under the steering wheel, is used to display the flashing diagnostic fault codes. This is also called the Malfunction Indicator Lamp (MIL). See Figure 1 on the next page. When the ignition key is turned to the “ignition” position the light comes on. The light goes out after the engine starts unless an active fault has been detected. When that happens the light remains on until the fault is cleared. The fault codes are stored in the memory of the Small Engine Control Module (SECM).

Displaying the fault codes

To display the fault codes:

  1.  Turn the ignition key on without cranking the engine.
  2. Depress the accelerator pedal to the floor three times within five seconds.

Clearing the fault codes

To clear the fault codes:

  1. Turn the ignition key on without cranking the engine.
  2. Depress the accelerator pedal to the floor ten times within five seconds.

Note: Do not clear the codes until the faults have been diagnosed and corrected.

Reading the fault codes

All fault codes are two-digit codes. When the codes are retrieved and displayed per the method above, the light flashes the appropriate number of times for each digit with a short pause between digits, and a long pause between fault codes. For example, “fault code 12” is displayed as one flash, then a .5 second delay, then two flashes. Then the code flashes again (or the next code) after a 1.2-second delay.

Code 12 is displayed at the beginning of every code list. For example, if two fault conditions exist and the SECM displays codes 52 and 74, the code list flashes 12, 52, 74, 12, 52, 74, 12, 52, 74, etc., using code 12 to indicate the beginning of the code list. Note: If no fault exists, code 12 flashes continuously.

Interpreting the fault codes

Some of the faults shut down the engine immediately, some cause a delayed shutdown. Some trigger a “limp home” mode. For others the SECM simply indicates a fault and takes no further action.

The following page is a list of all the fault codes with a brief description—a fault-code “cheat sheet” for LP engines. It is imperative that every Daewoo technician keeps a copy of this on hand as the new low-emissions trucks are placed in service. Daewoo suggests that technicians practice displaying fault codes on new trucks; code 12 can be displayed when no fault condition exists.


Woodward Industrial Controls has published a manual for each of the three types of engines equipped with their fuel system on Daewoo trucks. They contain detailed descriptions of the fault codes along with detailed troubleshooting procedures. The manuals can be found on our web site in PDF format, titled “Fuel System Supplement” in the Service Literature section. Please download these files to your computer as needed. As new versions of engine service manuals from Daewoo become available, they will also be posted to the web site, and be made available through our Parts Department. Please check the web site periodically for updates for your particular model and serial number.


The combination of the cheat sheet on the next page and the manuals from the Daewoo web site should allow technicians to get a good jump on troubleshooting should a fault condition develop. Please use the available tools before contacting Daewoo product support.

Daewoo Tier II engine/fuel system fault codes

12 NONE Signifies the end of one pass through the fault list
14 ECTSensorInputLow Normally set if the coolant sensor wire is shorted to ground
15 ECTSensorInputHigh Set if the coolant sensor wire is disconnected or open
16 ECTRangeHigh Coolant sensor has measured an excessive temperature or shorted to GND
22 ThrottleSensorInputLo TPS1 signal wire is open
23 ThrottleSensorInputHi TPS1 signal wire is shorted
24 ThrottleSensorRangeLo TPS Sensor malfunction
25 ThrottleSensorRangeHi TPS Sensor malfunction
26 ETCSticking ETC driver signal wire is open or the throttle plate is sticking inside the throttle body
27 PredictedTPSDifference TPS1 is different than calculated position
28 ETCSpringTestFailed Throttle return spring failed keyup test
29 ETCDriverFault Throttle driver over-current or driver signals shorted
33 MapSensorInputLow MAP signal disconnected or open circuit
34 MapSensorInputHigh MAP signal shorted or sensor failure
37 IATSensorInputLow TMAP sensor failure or shorted circuit
38 IATSensorInputHigh TMAP disconnected or IAT signal open
42 EST1Low Coil driver signal low or under current
43 EST1High Coil driver signal high or over current
52 LowOilPressure Low engine oil pressure
53 BatterySensorInputLow Battery voltage measured below 8.0 VDC
54 BatterySensorInputHigh Battery voltage measured above 15.9 VDC
55 XDRPSensorInputLow Measured sensor transducer power is below 4.6 VDC
56 XDRPSensorInputHigh Measured sensor transducer power is above 5.2 VDC
57 Engine OverSpeed RPM increased above maximum rpm setpoint
61 Pedal1SensorInputLo APP1 signal disconnected, open circuit or sensor malfunction
62 Pedal1SensorInputHi APP1 sensor failure or shorted circuit
63 Pedal1SensorRangeLo APP1 potentiometer malfunction
64 Pedal1SensorRangeHi APP1 potentiometer malfunction
65 Pedal2SensorInputLo APP2 sensor failure or shorted signal
66 Pedal2SensorInputHi APP2 signal disconnected, open circuit or sensor malfunction
67 Pedal2SensorRangeLo APP2 potentiometer malfunction
68 Pedal2SensorRangeHi APP2 potentiometer malfunction
69 Pedal1ToPedal2Difference Measured APP2 pedal position signal is different than APP1 signal
71 AFRTrimValveOutput FTV modulation driver signal fault
72 AFRTrimValveLowerDC FTV duty cycle at lower (LEAN) limit
73 AFRTrimValveUpperDC FTV duty cycle at upper (RICH) limit
74 O2SensorSwitching O2 sensor not switching across the reference AFR voltage
77 OxygenSensorInputHigh O2 sensor signal shorted to +5 VDC

One thought on “Daewoo forklifts fault codes list

  1. Charles jerkins

    if the engine will not start and there is no codes but if you unplug the secm to the distributor it will start but not accereate does tht mean the secm is bad


Leave a Reply

Your email address will not be published. Required fields are marked *