312C, 315C, 318C, 319C, 320C, 321C, 322C, 325C, 330C and M325C Excavators and 325C MHPU and 330C MHPU Mobile Hydraulic Power Units Engine and Pump Control – V2 – Troubleshooting Diagnostic Codes

Table 1
Component Identification (CID)    
CID No.     Name Of Component    
(Not in 321C)    
Throttle position signal    
96     Fuel level sensor    
110     Engine coolant temperature sensor    
167     Alternator    
168     Voltage to the power supply (keyswitch)    
190     Speed sensor    
( 319C, 320C, 322C, 325C, and 330C ONLY)    
Cat Data Link    
( 312C, 315C, and 321C ONLY)    
Electronic Control Module (ECM)    
( 312C, 315C, and 321C ONLY)    
Action Alarm    
(Not in 321C)    
Engine oil pressure fault    
374     Swing brake solenoid    
376     Travel alarm    
581     Proportional reducing valve for the power shift pressure    
586     Engine speed dial    
587     Feedback of the governor actuator    
( 312C, 315C, and 321C ONLY)    
Communication problem between controller and monitor    
590     Engine controller    
598     Automatic travel speed solenoid    
600     Hydraulic oil temperature sensor    
1161     Pressure sensor for the delivery pump (1)    
1162     Pressure sensor for the delivery pump (2)    
1525     Straight travel solenoid    
( 319C, 320C, 322C, 325C, and 330C ONLY)    
Travel alarm    

Illustration 1 g00691520

Example Of A Typical Troubleshooting Procedure

(1) Preparations

(2) Description of the problem

(3) Error code on the display

(4) Items that require checking

(5) Probable cause and solution

    Illustration 2 g00987164

    Diagram Of Terminology For The Troubleshooting Procedures

    (6) Number of the terminal in the connector

    (7) Indication of the short circuit

    (8) Number of the connector

    (9) “M” Male “F” Female

  1. Description (Items that require checking)
  1. Measurement of Voltage

    • (A) – (B) : 24 V

    Voltage is measured at the later terminal. For example, the red test pin + is connected to terminal “A” and the black test pin – is connected to terminal “B”.

  1. Meaning of Symbols
    1. The following list describes the meaning of specific symbols:

      • “C-ground” : Ground terminal for the chassis

      • “P-ground” : Ground terminal for the platform

      • “R-ground” : Ground terminal for the relay panel

      • “Cab-ground” : Ground terminal for the cab

  1. Preliminary Check
    1. Connector

      Check the connection of the connector before a troubleshooting procedure is performed. Inspect the connector for moisture. Moisture in a connector can cause a poor connection. Ensure that the connectors are mating correctly. Ensure that the pins in the connector are secure.

    1. Continuity

      Ensure that continuity is present between the following items:

      • “C-ground” – “P-ground”

      • “C-ground” – “R-ground”

      • “P-ground” – “Cab-ground”

      Turn the disconnect switch to the OFF position before you perform the continuity checks. The power is OFF in order to prevent damage to the tester and the circuit.

  1. Preparation
    1. Turn the key start switch to the OFF position.
    1. The hydraulic control lever is in the LOCKED position.
    1. Ensure that the controller, the harnesses and the connectors are connected.

      Note: Ensure that disconnected wires do not contact the machine in order to avoid damage to electrical components when power is applied.