JCB backhoe loses drive when you brake: transmission dump switch
Partager
Applies to: JCB 3CX, 4CX, 2CX, 1CX and 214-217 backhoe loaders
Symptoms
- Machine coasts with no drive after braking
- No push into a pile when you touch the brake
- Drive drops out intermittently
Why it happens
JCB backhoes have a transmission dump (declutch) switch that disengages drive when the brake is pressed, so full hydraulic power goes to the loader. If it's switched on, or the switch or brake pedal switch is faulty, drive cuts out.
How to fix it
- Check the transmission dump switch position on the dash or loader lever.
- Test the brake pedal switch and dump switch for correct operation.
- Check transmission oil level and filter.
- Test the dump solenoid on the transmission per the manual.
Tools and parts
- Multimeter
- Transmission oil and filter
What the factory service manual covers
Transmission: dump circuit, solenoid tests, oil spec and pressures. The full procedure, specs and wiring diagrams are in the factory service manual for your machine.