After powering on printer firstly initialize then all led are turn on & not getting ready...

contact your service provide for assistance on how to set it up

This is general error of the printer. When you have to change the new mother board you should be initialized it then it can be ready mode. When you try to initialization you need printer printer adjustment program. You can batter find out from google & write down EPSON Stylus R230 Printer Adjustment program or ink reseat program.

HP tech support might help you in this matter you can reach them directly on this number (877-690-9305) or just follow the link Support For Hp Printer

I've seen this exact error a few times on the 4101s & turned out to be a bad EIO hard drive.If you replace the drive, you'll most likely have to download the newest firmware & load it to get every feature back.
You can try & initialize the drive first though:
- Turn off printer
- Press & hold [Start] button
- Turn printer on, wait for all 3 LEDs to stay solid then release button
- Press & release [Left] arrow button (should read "Initialize Disks" on display
- Press & release [Select], then wait for printer to warm up
Listen also to the drive & if you hear it clicking over & over then it's bad & will need replaced.

Cold reset
A cold reset changes most system parameters in NVRAM to the factory defaults. However, unlike NVRAM inititialization, a cold reset does not reset the page count, the paper tray sizes, language, or formatter number.
Note If an HP Jetdirect card is installed, remove it before performing a cold reset. Otherwise, the procedure will also reset all the HP Jetdirect settings as well as the printer settings.
To perform a cold reset
1 Turn the printer off.
2 Press and hold down the GO button.
3 Turn the printer on, and continue to hold the GO button for at least 5 seconds, but not longer than 15 seconds. During this process, the Attention LED will turn on.
4 Release the GO button.
Note If both the Attention and the Ready LEDs turn on before you release the GO button, you must start the procedure again with step 1.
5 The printer's LEDs will begin cycling. The cold-reset process will
run until completion, and the printer will return to the ready state.

If not work, tris this

NVRAM initialization

CAUTION Only perform the following procedure if absolutely necessary.
Performing an NVRAM initialization resets some parameters that cannot be restored later.
NVRAM initialization sets all default variables stored in NVRAM back to factory default values or to a default ROM value, depending on the variable. It also performs a system reset.

NVRAM initialization resets the following:

• all menu settings to factory default values

• factory settings such as formatter number, page counts, and factory paper settings
  

To perform NVRAM initialization
1 Turn the printer off.
2 Press and hold down the GO button.
3 Turn the printer on, and continue to hold the GO button for at least 20 seconds. During this process, the GO button, Attention, and Ready LEDs will each turn on.
4 Release the GO button.
5 The printer LEDs will begin cycling. The NVRAM-unit process will run until the printer is in the ready state.

Please do the following:-

1. The printer is turned off and plugged the power cord.
2. Press Resume button 2 seconds
then press the POWER button until the green light on (when pressing the POWER button, Resume button ... jgn released first)
3. Then release the RESUME button, but do not release the POWER button.
4. While the POWER button is still depressed, press the Resume button 5 times. Led will light turns green orange with the last glow orange. (Do not be mistaken 4x because the printer will die completely, but it is temporary too) Then ...
5. Release both buttons simultaneously.
6. Led will blink briefly and then will glow GREEN.
7. And the computer will detect new hardware, just ignore ...
8. Press the POWER button, then the printer will die.
9. Press the POWER button again then the printer will flash and ... Printer is ready for use.

I hope this solution will helpful for you
Please don't forget to click on Four thumbs which are given below & then write testimonial for my appreciation if it is helpful
THANKS & Keep Using fixya

Try an NVRAM initialization
Turn printer OFF
Press and hold the GO button
Turn printer ON, continue to hold the GO button for at least 20 seconds. The GO, Attention and Ready LEDs each turn on.
Release the GO button.
The printer lights will cycle. After the initialization the printer will return to the ready state.

To check the light Pattern of your printer

Click on Light and Error HP Laser jet 1012 Printer

Check the error details from the above link

Condition of the printer Action/Description Ready

The printer is ready to print. No action is necessary. Processing

The printer is receiving or processing data. Wait for the job to print. Processing...(job name) Ready LED is blinking.

This message is displayed while the printer is processing a current job, but has not begun to pick pages. Processing...(job name) From Tray XX Ready LED is blinking.

This message comes up for any job, once the printer starts to pick paper. Manual Feed or Continuable Error

The printer is attempting to Manual feed, media is not loaded in the paper tray, media loaded is the wrong size or type. Verify that the correct media is loaded.

Press and release the GO button to continue printing. Out of memory

The printer is out of memory. The page you are printing might be too complex for the printers memory capacity. Try lowering the resolution. See Understanding print quality settings for more information. Door open, media out, no print cartridge, or media jam

The printer is in an error state that requires operator intervention or help. Check the following:

• The print cartridge door is completely closed.
• Media is loaded.
• The print cartridge is correctly installed in the printer.
• There is no media jam.

Printer initialization

A printer initialization is taking place. No action is necessary. Fatal error

All lights are on.

• Unplug the printer for 30 minutes, and then plug it back in.
• If the printer still has an error, contact HP Support.

All lights are off.

• Verify that the printer is turned on.
• Make sure that there is power.
• Unplug both ends of the power cord, and plug them back in.

Job Cancel

All the LEDs cycle. Canceling...(job name)

The Job Cancel button was pressed and the job is aborted. Power ON

All the LEDs cycle. Checking Paper Path and Checking Printer

This only occurs at power up. Cleaning mode/Engine test

A cleaning page or engine test page is printing.

All the LEDs cycle. Cleaning Page prints

Wait until the cleaning page is finished printing and the printer is in Ready mode. This could take up to two minutes.

Wait until the engine test page is finished printing and the printer is in Ready mode. Clearing Event Log

All the LEDs cycle.

This will happen automatically during an NVRAM Init and a cold reset. No message will be displayed. No Action is Necessary. Power On

Initializing

This occurs when the product is powered on and coming out of EDOS. No Action is Necessary.

restart than on

Hello,

It seems that none of the printer's sensor is faulty, in fact, the printer has a faulty firmware on the formatter.

Your printer may need replacement of the formatter board, however, please try the following before swapping the formatter.

HP LaserJet P2015 Printer Series - Paper Jam Light Solid ISSUE: The HP LaserJet P2015 may come up with Paper Jam Light solid and would show the same light pattern even if the printer is power cycled.
SOLUTION: The Light pattern is as shown in the diagram below.

Perform the following tasks in the order listed.
1. Reset the printer using the Super NVRAM initialization. The procedure is
a. Turn off the printer
b. Press and hold the GO button
c. Turn on the printer and continue to hold the Go button for at least 50 seconds. During this process the Attention, Ready and Go light turns on. Then the Attention and Ready light turns off, leaving just the Go light illuminated.
d. Release the Go button. The Go, Attention and Ready lights turn on.
e. Press and hold the Go button. All lights turn off. During the next three seconds, the Go, Ready and Attention lights turn on in that order, one per second.
f. Release the Go button to perform the initialization. The control panel lights begin cycling from front to back. After the Super NVRAM initialization process is complete, the printer returns to the ready state.
2.Unplug the power cord when the printer is on and leave it unplugged for 10 Seconds.
3. Turn the printer back on.
If the above steps resolve the issue, then print a configuration page and check the firmware version and the formatter board no.,
If the firmware version is below: 20080312, then your printer needs to upgrade the firmware, however the firmware can be upgraded only onl those models whole formatter board's third number from left is 0, 1 or 2, eg: JK0xxxx

If the 3rd number from left of the formatter board no is anything other than 0, 1, 2, then firmware cannot be flashed.

Please let me know the next update.

- Nikhil