I accidently locked my masterlock 1590D and don't know the code

Here is the instruction sheet:

http://www.masterlock.com/pdfs/5400D_Instructions_Sheet.pdf

If this is an older masterlock with a serial number, you can fill out the form located here http://www.masterlock.com/pdfs/lost_combo_form.pdf
Read the below from masterlocks website: Due to increased security concerns nationwide, Master Lock recognizes the heightened need for additional safety measures. We no longer provide lock combinations in response to phone, fax, or email requests. Please follow the procedure outlined below to obtain the combination to your lock and submit your request to:
Master Lock Warehouse
1600 W. La Quinta Rd
Suite/WHSE # 1
Nogales, AZ 85621Procedure:

• Print out the Lost Combination Form from a printer friendly page, or download the PDF file.
• Have your Lost Combination Form notarized by a Notary Public to prove that you are the owner of the lock (you can include up to 6 combinations on one notarized form).
  
  • Note: Inmates at a correctional facility - in addition to the lost combination form, you must submit your request on official prison letterhead. In lieu of notarization, the form must be signed by a prison official.
• Photocopy the serial number on the back case of your combination lock. This copy MUST clearly show that the lock is not attached to anything. Be sure to hand write the serial number on the photocopy.
• Mail the original completed, notarized Lost Combination Form and the photocopy of the back of your lock to the address above.

Note: It will take approximately 4 to 6 weeks to process your request for a combination.

Note: If the form is not fully completed and notarized with a raised seal or rubber stamped seal, or if the serial number is not legible on the photocopy, your request will not be honored. Master Lock does not reimburse for any Notary fees.

If you remember the first letter/number you're still in luck. What you need to do is start off with that letter. If you know what you tried to set, ex. ATE

Work with
A
A, D, E, H, J, L As for the last number/letter, all you have to do is keep spinning it right and you will hit it.

For me, I tried fooling around and setting ALT

However, when I was entering the new combo, I turned 3times or more right when key was in to A, then a full circular left turn past A to L. From L, I turned the same direction 4 clicks to T and locked it. I realized I entered it wrong when I locked it. How these locks were designed isn't that complicated. It consists of 3 different turns. Right, left, right. Right to A, left to L, right to T. When I had entered, right to A, left to L, and left again to T. It automatically makes the second letter/digit the same as your first letter/digit. I cracked my lock trying all combinations of A,L,T. Writing a list helps. But I also suggest your write down a list of your first digit twice.

A, A, L A, L, A
A, L, T A, A, T (That's what my code was after incorrectly trying to set it as "ALT")

However, this is only one method. When I had purchased the lock a year ago and set a combination. I approached it with a different method. The first one as I mentioned. I had tried to set EAT to test. The combo ended up being a letter or two off in the combo itself. So my cracked combo was not EAT but something _AT or EA_ or E_T. Combos usually aren't off by a whole lot. I was going to throw my lock away and buy a new one, but I cracked it :) I know this is alot about my own experience, but don't give up! I was planning on solving it, but I did it within 10mins! Not so tough !

• Set your own combination using 3-letters or numbers or a mix of both
• Combination easy to change with included reset tool
• Maximum security with anti-shim feature
• Hardened steel shackle for increased bolt cutter protection
• High precision dial clicks for fast accurate dialing

HI

http://www.askdavetaylor.com/lg_cellphone_locked_needs_puk_code_help.html

Sorry, I don't think there is a remedy, but you could try removing it, and reinstall again.

had your looking for a combo, throw it out. no way to find the combo for it. serial only refers to the model of the lock. its like asking for a part for " my ford truck " not enough info.

mine has done the same... has yours fixed yet?

There is a list of name combinations at the masterlock website, perhaps that will jog your memory. http://www.masterlock.com/pdfs/Precision_Dial_1590D_Instructions.pdf

Hope this helps:)

open the shackle twist 180 degrees...shut it as if u were closing it into the locking device..hold it down, put in what ur new combination is..pull the shackle up and shut it into locking device, and test it out.