Assessing OEM Door Lock Module (DLM) and solenoids

[PJ Grady Inc.]

The design problem with the OEM and original LockZilla was the way they created the time delay for solenoid operation. Both designs used a 1000 uf. capacitor that powered the relay coil. That results in the relay coil voltage slowly dropping which caused the relay contacts to also open slowly and burn the contacts. The LockZilla used 70 amp relays so its contacts may last longer.

You might say that as out of hundreds of units sold I can't ever recall one failing....not even after 20 years!
Rob

[DMC-81]

Great discussion so far.

On the question of why not just get a new system? In my case, the answer is aligned with my restoration goal: "mostly correct, with known flaws corrected". If my OEM lock system is in good condition, a small upgrade that addresses the flaw is a good investment in keeping it original. Other than that, a digital controller, launchers, and remotes are very cool! I'm really glad there's 2 options: uprated OEM, or a modern system. Win win!

[sdg3205]

You can get the original equipment to work, it just takes patience. Just swap in new relays and go from there.

[David T]

You can get the original equipment to work, it just takes patience. Just swap in new relays and go from there.

I agree but your answer is too simplistic. It all starts with properly adjusting the doors. Then, if necessary, repairing or replacing the solenoids if they are burnt. Then adding the 10A in-line fuse. The relays burning up are a symptom, not a cause.

[Bitsyncmaster]

The other problem with the OEM and Zilla controller is the standby current draw of 12 ma. This is the main reason people need to install a battery disconnect switch. Elvis posted a circuit change to reduce that standby current which could be implemented on those controllers. I did post a new design a long time ago but there was not much interest so I never made a PCB for it.

[David T]

The other problem with the OEM and Zilla controller is the standby current draw of 12 ma. This is the main reason people need to install a battery disconnect switch. Elvis posted a circuit change to reduce that standby current which could be implemented on those controllers. I did post a new design a long time ago but there was not much interest so I never made a PCB for it.

The current drain only becomes a problem if you either have an already bad battery and/or you don't use the car for over a month. In any case you can still retain the OEM module with that circuit change, it is not very hard to do if you can solder. I agree the best option would be a Lockzilla if you can find one and are willing to pay the price. There are some owners that are very frugal and want to spend the least amount possible. That means fixing what you got. Putting in the battery master switch has other benefits besides eliminating the standby current draw so you may want to do that anyway.

[Elvis]

hey the old power lock thread :-)

use the search !

few dollar of parts and it's not worse or better than that Japanese monster ( believe me or not - I don't care anymore, have other problems)

INSTALL THE FUSE !!!!!!
10 A !!!!


enjoy a working power lock system, mine works since I updated it and ~ 70...100 other, too.

a remote can easily be installed, too. I have two here that are tested on my car and work.

4 wires to solder - done !

PM me if interested.

have a nice weekend

[DMC-81]

Gentlemen, thanks for all the very helpful information.

I will research more, and assess the other solenoid. I'll loop back and post my solution here as well.

[lsoasey]

I'm going through a similar process as DMC-81 of evaluating the door lock module solenoids in my car. I'm interested in upgrading the components within my original Door Lock Module as described by Elvis' nice PDF. Can anyone provide a web link or part number for the a relay replacement which is physically pin compatible with the original relays on the board? I can see that suppliers like Digi-Key have many options which are electrically compatible -- I'm just uncertain on the pin alignment. I haven't been able to find a recommendations here via the forum search. (I'll apologize in advance if it has been posted already. I may not be using the proper combination of keywords...) I think I can find the transistor and resistors.

Thanks!

[Bitsyncmaster]

Your probably going to find a relay rated for the same current for an exact fit on the circuit board (if you can even find one). I would just recommend you inspect the relay points and file them if necessary and add the 10 amp fuse to protect things.

Now if you want to get creative you could wire in a standard 40 amp relay but you would need to cut the DLM box for clearance.