Page 4-4
Troubleshooting
4.2 - Cause and Remedy
TM12 Work Platform - European
No drive reverse but
drives in forward. Lift
function operable.
1. Faulty Drive/Lift Selector Switch
Test Drive/Lift Switch for continuity. Replace if faulty.
2. Faulty Diode
Test Diode. replace if faulty.
3. Faulty Reverse Coil
Test Reverse Coil, if proper voltage is present and coil is not
magnetized, replace.
4. Faulty Counterbalance Valves
Check pressure of Counterbalance Valves. Replace or reset valves
as required.
No drive reverse but
drives in forward. No
lift functions.
1. Faulty Drive/Lift Selector Switch
Test Drive/Lift Switch for continuity. Replace if faulty.
2. Faulty Controller
Check operation of Controller Switch. Replace if required.
3. Faulty Down/Reverse Relay
Test Relay, replace if faulty.
Platform will not
elevate or elevates
slowly.
1. Emergency Down Valve open
Close Emergency Down Valve.
2. Platform overloaded
Observe maximum load rating.
3. Faulty Diode
Test Diode, replace if faulty.
4. Faulty Lift Valve Coil
Test Lift Valve Coil. If proper voltage is present and coil is not
magnetized, replace.
5. Faulty Drive/Lift Selector Switch
Test Drive/Lift Switch for continuity. Replace if faulty.
6. Lift Relief Valve out of adjustment or faulty
Adjust the Lift Relief Valve. If not adjustable, replace.
7. Drive/Lift Valve sticking
Replace the Lift Valve.
8. Faulty Up/Fwd Relay
Test Relay, replace if faulty.
9. Faulty Controller
Check operation of Controller. Replace if required.
10. Faulty Lift Flow Control
Replace Flow Control.
Platform drifts down
after being elevated.
1. Emergency Lowering/Down Valve partly
open or faulty
Ensure that the Emergency Lowering Valve is completely closed.
Replace the valve.
Platform will not
lower. Drive function
operable.
1. Faulty Down Valve Coil
Test Down Valve Coil. If proper voltage is present and coil is not
magnetized, replace.
2. Faulty Drive/Lift Selector Switch
With the Drive/Lift Switch in the LIFT position, check continuity.
Replace if defective.
3. Down Valve stuck
Replace the Down Valve.
4. Plugged Down Orifice
Remove and clean orifice.
5. Velocity Fuse Valve sticking or frozen
Repeat lifting and lowering platform to warm oil, if possible move
machine out of cold environment, replace the Velocity Fuse Valve.
Motion Alarm does
not sound.
1. Faulty Down Alarm
Check voltage to Down Alarm. If proper voltage is present,
replace the Alarm.
2. Faulty Relay
Test Relay. Replace if faulty.
Brake will not
release.
1. Brake Orifice plugged
Remove and clean Orifice.
2. Faulty Brake Cylinder
Check and replace seals in Brake Cylinder.
3. Brake out of adjustment
Adjust nut to disengage brakes from tires when driving only.
Brake will not lock
wheel.
1. Brake Orifice plugged
Remove and clean Orifice.
2. Faulty Brake Cylinder
Check and replace seals in Brake Cylinder.
3. Brake out of adjustment
Adjust nut so brakes fully engage tires when not driving.
Table 4-1:
Cause and Remedy (Continued)
TROUBLE
PROBABLE CAUSE
REMEDY
Summary of Contents for TM12
Page 1: ...TM12 ...
Page 10: ...Page VI Table of Contents List of Tables TM12 Work Platform European NOTES ...
Page 60: ...Page 3 34 Maintenance 3 18 Torque Specifications TM12 Work Platform European NOTES ...
Page 74: ...Page 5 6 Schematics 5 3 Hydraulic Tm12 Work Platform European NOTES ...
Page 79: ...Page 6 5 Illustrated Parts Breakdown TM12 Work Platform European NOTES ...
Page 81: ...Page 6 7 Illustrated Parts Breakdown Basic Assembly TM12 Work Platform European ...
Page 88: ...Page 6 14 Illustrated Parts Breakdown Hose Kit TM12 Work Platform European ...
Page 101: ......