The cab heater controls A and associated cables are housed in the R.H. side console as shown.There are two control cables which operate the re-circulation vent and the hot water valve. Both the cables can be accessed by removing the side console instrument panel.

JCB ServiceMaster 4 2023
JCB Service Parts Pro + 2017 Service Repair

Removal
1 Park the machine 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 the fixing B at the top of the instrument panel and carefully lift the panel forward to reveal the connections at the back.
3 Disconnect the temperature control cable C by releasing the cable outer sheath from the clips R at each end, and unhooking the cable from the water valve lever S and from the pin T at the control knob.4 Disconnect the re-circulation vent cable D by releasing the cable outer sheath from the clips X at each end, and unhooking the cable from the vent Y and from the pin Z at the control knob.

Replacement
Replacement is the reverse of the removal sequence.
After fitting the cables, operate the heater controls and check that they function correctly.

Adjustment
If the control cable C is not correctly assembled it is possible that the heater cannot be turned fully off.

To ensure that the heater can be turned fully OFF, the temperature control cable C should be adjusted so that the water valve will close FULLY within the range of movement of the control knob as follows:
1 Set the water valve control lever S to the fully closed position.
2 Turn the heater control knob E a small amount clockwise from the closed position, i.e. a fraction before the cold position on the decal as shown.
3 Tighten the cable clips R to clamp the cable outer sheath.
4 Check the heater control range of movement and that the water valve can be fully closed by turning the knob.

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