Hp LJ 4 "57 service" code

[kmguy31]

i have an ancient hp lj 4 that i am working on. It has a "57 service" code. All manuals point to main motor. So i ordered main motor and replaced it. I am still getting the error code!!! Any ideas would be greatly appreciated!!

[fixthecopier]

Since you looked it up, you also know to check the DC controller. I would look at the cartridge and make sure it is not in a bind causing the motor not to move.

[prntrfxr]

Hp LJ 4 "57 service" code

It's very common for coupler gear on the main drive asm to either seize up or break also possibly bad/broken fuser gears. After gear drive, motor (which you already changed), and lastly DC Controller. Although its possible that the problem is electronic, mechanical failure is more likely.

RF5-0350 Drive Coupler
RS5-0237 Gear, 17T/32T (recommend replacing together)
or replace the entire drive RG5-0457 asm

RG5-0511 DC Controller

Hope this helped you.