asd-a2 e delta homing

hi guys
i have a machine with 5 asd-a2-E servos for over a year
two of my servos(Z &W axis) had problem in homing since begining. each time that a started machine and clicked on home all, all servos start homing as the order in ini file but this two drives shows as it is homed but they does not start homing. i had to click on home joint 1 and joint 4 several times in order for them to do homing . sometimes i had to do it ten times and some time just once . 
today , this drives did not do homing even after 100 times of clicking on home.
i reseted their parameters but it did not solve the problem. 
do you guys know how to fix this problem ?

i had to add that all their sdo's and register are like my other drives. xml of them are just a copy&paste of other axeses.
drives manufactoring date are different.

when i click on home these joints, their cia402.1.stat-homing becomes high and remains high
joint.1.homing becomes high and then low and joint.1.homed becomes high

Not sure but I guess that would indicate that the drive is running its internal homing procedure but does not succeed in finishing it.

status word and controlword changes for a short time and it should trigger the internal homing but it does not succeed doing so.

 
I am working on a LinuxCNC configuration for a CNC machine with EtherCAT-based servo drives (Delta ASDA-A2-E). The machine has 5 axes (`X`, `Z`, `A`, `C`, `W`), and I am experiencing an issue with the `W` axis during the homing process. Here are the details:

1. **System Overview:**
   - EtherCAT master is configured in ethercat-conf.xml.
   - The `W` axis corresponds to `slave idx="4"`.
   - The drive uses the CiA 402 profile, and homing mode is set to `02 00` (Homing Mode 2).
   - The `W` axis is not on its limit switches, and the `in-home` signal is not falsely triggered.

2. **Observed Behavior:**
   - When I click "Home All" or "Home W" in LinuxCNC:
     - `joint.4.homing` turns `TRUE` briefly and then turns `FALSE`.
     - `cia402.4.stat-homing` turns `TRUE` and remains `TRUE`.
     - `joint.4.homed` turns `TRUE`, indicating LinuxCNC believes the homing process is complete.
     - However, the servo does not move at all during this process.
     - The `opmode` for the `W` axis remains at `8` (Cyclic Synchronous Position) instead of switching to `6` (Homing Mode).

3. **What I Have Checked:**
   - EtherCAT communication is operational (`ethercat slaves` shows all slaves in the `OP` state).
   - HAL connections for the `W` axis are identical to the working `X` and `Z` axes:
     ```plaintext
     net w-home-index <= joint.4.index-enable  => cia402.4.home
     net w-enable     <= joint.4.amp-enable-out => cia402.4.enable
     net w-amp-fault  => joint.4.amp-fault-in   <= cia402.4.drv-fault
     net w-pos-cmd    <= joint.4.motor-pos-cmd  => cia402.4.pos-cmd
     net w-pos-fb     <= joint.4.motor-pos-fb   <= cia402.4.pos-fb
     ```
   - The `in-home` and `zpulse` signals are mapped in ethercat-conf.xml but do not seem to trigger during homing.
   - Homing speeds (`6099`) and other SDO configurations are consistent with the working axes.
   - The `statusword` (`cia402.4.statusword`) does not indicate any faults, and the drive is in the "Operation Enabled" state.

4. **What I Need Help With:**
   - Why is the `W` axis not initiating the homing process, even though LinuxCNC believes it has completed?
   - Why does the `opmode` not switch to `6` (Homing Mode) during the homing process?
   - Are there any additional checks or configurations I should perform in ethercat-conf.xml, lathe.hal, or the drive itself?

5. **Additional Context:**
   - The `W` axis used to home successfully in the past but stopped working recently.
   - The `Z` axis occasionally exhibits similar behavior but eventually completes homing after several attempts.

Please provide detailed troubleshooting steps or suggestions to resolve this issue.