Troubleshooting - Terex PT-30 Service Manual

Compact Track Loader

15. Troubleshooting

Troubleshooting
This section identifies selected problems and sug-
gests probable causes.
Problem 1
Machine will not crank over.
Probable cause
1. Auxiliary hydraulic switch activated.
2. Weak or dead battery.
3. Battery cables loose or corroded.
4. Ignition fuse blown.
5. Main starter fuse blown.
6. Starter relay malfunctioning.
7. Bad ignition switch.
8. Bad starter.
9. Poor wire connections at key, relay, or starter.
Problem 2
Machine cranks but will not start.
Probable cause
1. Injection pump fuse blown.
2. Main power fuse B blown.
3. Main power relay B not activating.
4. Poor wire connection at injection pump or fuse.
5. Glow plugs not heating. (Will see black smoke.)
a) Main glow plug fuse blown.
b) Glow plug relay not activating.
c) Poor wire connections at ignition switch, relay,
or glow plug strip.
d) Failed glow plugs.
e) Bad ignition switch.
Problem 3
Machine starts but hydraulics will not operate.
Probable cause
1. Lap bar must be in down position, operator must be
seated in seat, and front door (if installed) must be
closed.
2. Safety fuse blown.
3. Faulty operator presence switch.
a) Test continuity through seat, lap bar, and door
switch. Adjust or replace as necessary. Lap bar
and door switch are magnetic switches and
should be adjusted to approximately 1/16 inch
(.16 cm) away from steel pickup bracket.
4. Poor ground (check ground wires on bottom left rear
side of hydraulic reservoir).
5. Safety relay is not activating.
6. Faulty safety solenoid or safety solenoid spool.
7. Poor wire connections on fuse, relay, or safety sole-
noid.
8. Low charge pressure.
Problem 4
Loader operates but tracks will not move.
Probable cause
1. Leak in feed line to pilot control.
2. Pilot control malfunctioning.
Problem 5
Tracks operate but loader will not operate.
Probable cause
1. Auxiliary direction switch activated sending oil over
relief.
2. Check to see if auxiliary flow works. (If auxiliary
flow works, skip to number 5).
3. Main auxiliary relief malfunction.
4. Auxiliary pump bad.
5. Leak in feed line to loader control pilot.
6. Loader control pilot malfunctioning.
Problem 6
Auxiliary flow does not work. Loader works.
Probable cause
1. Auxiliary hydraulic fuse blown.
2. Faulty ground wire.
a) Clean ground connections on left rear side of
hydraulic tank.
3. Auxiliary hydraulic direction switch failure.
4. Poor wire connections at fuse, direction switch, or
pin connector P17.
5. Auxiliary hydraulic pilot generation spool stuck.
6. Bad or not fully connected Quick-Coupler
Problem 7
Auxiliary hydraulic part-time thumb switch operates but
full-time flow direction switch will not operate.
Probable cause
1. Auxiliary direction switch faulty.
2. Poor wire connections at mode switch or direction
switch.
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