How to Remove and Replace Cab Heater Controls for JCB 3CX Loader

This guide provides instructions on how to remove, replace, and adjust the cab heater controls for JCB 3CX, 4CX, 214, 215, 217, and their variants backhoe loaders.

Related Resources

• 2025 JCB ServiceMaster 4 v25.1.0 – Free Download for Windows 10/11
• 2017 JCB Parts Plus+ and Repair Service Manual
• JCB Diagnostic Tool

Cab Heater Controls Overview

The cab heater controls (A) and associated cables are located in the right-hand side console. Two control cables are used:

• Temperature control cable (C): Operates the hot water valve.
• Re-circulation vent control cable (D): Operates the re-circulation vent.

Both cables can be accessed by removing the side console instrument panel.

Removal Procedure

1. Prepare the Machine
   • Park on firm, level ground.
   • Apply the parking brake.
   • Lower the loader arms and excavator to the ground.
   • Switch OFF the engine and remove the starter key.
2. Remove Instrument Panel
   • Undo the fixing (B) at the top of the instrument panel.
   • Carefully lift the panel forward to access the rear connections.
3. Disconnect Temperature Control Cable (C)
   • Release the cable outer sheath from clips (R) at each end.
   • Unhook the cable from the water valve lever (S) and from the pin (T) at the control knob.
4. Disconnect Re-Circulation Vent Cable (D)
   • Release the cable outer sheath from clips (X) at each end.
   • Unhook the cable from the vent (Y) and from the pin (Z) at the control knob.

Replacement Procedure

Replacement follows the reverse order of removal.

After refitting the cables, operate the heater controls to ensure they function correctly.

Adjustment Procedure

Improper installation of the temperature control cable (C) may prevent the heater from shutting off completely. To adjust:

1. Set the water valve control lever (S) to the fully closed position.
2. Rotate the heater control knob (E) slightly clockwise from the closed position (just before the cold position on the decal).
3. Tighten cable clips (R) to secure the cable outer sheath.
4. Check full range of heater control movement and confirm the water valve closes fully when the knob is turned.