I have a jcb 214s will operate forward&reverse in any gear for approx. 20 minutes then seizes up and won't go either direction. Replaced layshaft-mainshaft valve and solenoids, replaced 4 wd valve and solenoid, replaced brake switch. Changed oil and filter. Not fixed .

https://www.tractorforum.com/threads/jcb-3cx-movement-problems.17257/

Check this forum out.

All to do with electronics and microswitches.

https://www.google.com/search?q=JCB+Backhoe+won%27t+go+into+reverse

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I recently tried the DIY service and repair manuals from a website and it actually helped me repair transmission problem in my jcb 3cx site-master.
It would'nt move forward or reverse, engine was good both solenoids for forward and reverse worked, but still couldn't diagnose the problem.
I don't have much technical knowledge but I just followed it step-wise, and now it works perfect! covers wiring, codes, diagrams, torque specs, PCV, everything
got it from www.reliable-store.com

I recently tried the DIY service and repair manuals from a website and it actually helped me repair transmission problem in my jcb 3cx site-master. It wont move forward or
reverse, engine is good both solenoids for forward and reverse work.
I don't have much technical knowledge but I just followed it step-wise, and works perfect! got it from www.reliable-store.comAll the best

Greetings, I read your question and I think Reliable-Store can help you in this. Here's the site link.
Jcb Service Manuals

I used to work on one of these , I think these are electronic shift modules , may be a dirty plug on the trans , may have the linkage off ,I forget ,

I recently tried the DIY service and repair manuals from a website and it actually helped me repair transmission problem in my jcb 3cx site-master. It would'nt move forward or reverse, engine was good both solenoids for forward and reverse worked, but still couldn't diagnose the problem.
I don't have much technical knowledge but I just followed it step-wise, and now it works perfect! covers wiring, codes, diagrams, torque specs, PCV, everything
got it from www.reliable-store.com

not reverse working

there will be oil leak or malfunctioning in the front & reverse gear ratio..its better to get ir repaired by a Mechanic
Thanks for rating Good luck

call your dealer to get an estimate too.

Shift Patterns Upshifts
Transmission upshifting is controlled by the powertrain control module. The PCM receives inputs from various engine or vehicle sensors and driver demands to control shift scheduling, shift feel and torque converter clutch (TCC) operation.
The PCM has an adaptive learn strategy to electronically control the transmission which will automatically adjust the shift feel. When the battery has been disconnected, or a new battery installed certain transmission operating parameters may be lost. The Powertrain Control Module (PCM) must re-learn these parameters. During this learning process you may experience slightly firm shifts, delayed, or early shifts. This operation is considered normal and will not affect the function of the transmission. Normal operation will return once these parameters are stored by the PCM.
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Apply Components Band — Overdrive
For component location, refer to Disassembled Views in this section.
During 2nd and 5th gear operation, hydraulic pressure is applied to the overdrive servo.

• This pressure causes the piston to move and apply force to the band.
• This action causes the overdrive band to hold the overdrive drum.
• This causes the overdrive sun gear to be held stationary through the adapter plate and the overdrive drum.

Band — Low/Reverse
For component location, refer to Disassembled Views in this section.
During 2nd gear operation, 1st gear operation and reverse, hydraulic pressure is applied to the low/reverse servo.

• This pressure causes the servo to move and apply force to the low/reverse band.
• This action causes the low/reverse brake drum to be held.
• This action causes the low/reverse planetary assembly to be held stationary.

Band — Intermediate
For component location, refer to Disassembled Views in this section.
During 3rd gear operation, hydraulic pressure is applied to the intermediate servo.

• This pressure causes the servo to move and apply force to the intermediate band.
• This action causes the direct clutch drum to be held.
• The intermediate band holds the intermediate brake and direct clutch drum to the case in 3rd gear.
• This causes the input shell and forward sun gear to be held stationary.

Clutches — Direct
For component location, refer to Disassembled Views in this section.
The direct clutch is a multi-disc clutch made up of steel and friction plates.

• The direct clutch is applied with hydraulic pressure and disengaged by return springs and the exhaust of the hydraulic pressure.
• It is housed in the direct clutch drum.
• During 4th, 5th, and reverse gear application, the direct clutch is applied transferring torque from the forward clutch cylinder to the direct clutch drum.
• This action causes the forward sun gear to drive the pinions of the low/reverse planetary carrier.

Clutches — Forward
For component location, refer to Disassembled Views in this section.
The forward clutch is a multi-disc clutch made up of steel and friction plates.

• The forward clutch is applied with hydraulic pressure and disengaged by return springs and the exhaust of the hydraulic pressure.
• The forward clutch is applied in all forward gears.
• When applied, the forward clutch provides a direct mechanical coupling between the center shaft and the forward ring gear and hub.

Clutches — Coast
For component location, refer to Disassembled Views in this section.
The coast clutch is a multi-disc clutch made up of steel and friction plates.

• The coast clutch is applied with hydraulic pressure and disengaged by return springs and the exhaust of the hydraulic pressure.
• The coast clutch is housed in the overdrive drum.
• The coast clutch is applied when in 1st, 3rd, D4, and reverse positions.
• When applied, the coast clutch locks the overdrive sun gear to the overdrive planetary carrier, thus preventing the one-way clutch from overrunning when the vehicle is coasting.
  • This allows the use of engine compression to help slow the vehicle and provide engine braking.

Clutches — Intermediate
For component location, refer to Disassembled Views in this section.
The intermediate clutch is a multi-disc stationary clutch made up of steel and friction plates which are in a module assembly that includes the cylinder and frictions.

• Applied with hydraulic pressure.
• Disengaged by a return spring and releasing of hydraulic pressure.
• Hydraulic pressure is feed through a feed tube in the case worm trail.
• Uses a bonded piston in an aluminum housing.
• Applied in during a 2-3 shift event.
• Transfers torque from the sun gear to the planetary carrier.
• Torque transfer causes the one way clutch to engage and holds the sun gear from turning, delivering 3rd gear.

One-Way Clutch — Direct
For component location, refer to Disassembled Views in this section.
The direct one-way clutch is a sprag-type one-way clutch that is pressed into the center shaft.

• The direct one-way clutch is driven by the ring gear of the overdrive planetary carrier.
• The direct one-way clutch holds and drives the outer splines of the center shaft in 1st, 3rd, 4th and reverse gears.
• The direct one-way clutch overruns during all coast operations and at all times in 2nd and 5th gear.

One-Way Clutch — Intermediate
For component location, refer to Disassembled Views in this section.
The Intermediate One-Way Clutch is a sprag type one-way clutch.

• The Intermediate One-Way Clutch connects the intermediate assembly to the input shell and sun gear assembly in third gear.

One-Way Clutch — Low/Reverse
For component location, refer to Disassembled Views in this section.
The low/reverse one-way clutch is a sprag type one-way clutch.

• The low/reverse one-way clutch holds the low/reverse drum and low/reverse planetary assembly to the case in 1st and 2nd gear.
• In all other gears the low/reverse one-way clutch overruns.

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