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Full Version: Door Lock Modules : Upgrade
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Hi all

This is just a tester but a few years back I re designed the lock module to use more modern components. It does NOT use the old circuit board at all and it does not use relays, its a totally new PCB and components. The only bit I utilise is the box and loom. I have also added an additional plug for lock / unlock using a remote alarm ect so no need to cut, splice or scotch lock..heaven forbid the loom.

The prototype was in my car for over a year and it went with the car when I sold it to MrP Smile.
Now its not a microcomputer that DMCH / DPNW sell but there again would be a lot less than the £100+ plus would look stock Smile

I have not put any costs together yet but would imagine the price would be under £40 and I would require your old module or if your handy with a soldering iron I would just supply the built PCB and you could swap over your box / loom.

I do have enough parts to build 1 module currently so if anyone is interested in that PM me. Otherwise if there is not enough intrest I will not give up my day job :lol:

Thanks
mmmm, I wonder if i'll need one of these??? Smile Cheers for the keys, they arrived yesterday!!!
Ben
I know this is an old thread, but whats the latest with this? My lock module is a stock one at the moment, I saw this list of parts that Nick made http://www.deloreans.co.uk/forum/viewtopic.php?t=946 but that still uses a relay. What does everyone recommend doing to a stock module? And what is the reason for doing these updates?
It is recommend to change the electronic component listed in the topic you just said for sagety reason and reduce the power current.
It also avoid to the relay to stay on and burn the solenoid of the door.
I know lot of people did this and also upgrade their door's solenoid but I'd rather change the lock door module for an improved one like DMCH has on stock. I know DPNW has also the same module, the color isn't the same but the inside is.
Hope my little explanation helps you?
If you want to take a look, it is the gold module :wink:
My dock lock
http://www.dmcnews.com/Techsection/doorlocks.htm

The originalmodule has a stupid design. However, driving a pair of standard DIN relays off the lock module bypasses the problem of switching the relays carryign the current with a decaying voltage - although it adds stuff to your relay compartment.

The number 1 thing to do with a stock lock module is to replace the relays with hermetically sealed units. These will still arc internally but can't oxidise and can't weld themselves shut in this way.

I used to rebuild them and later got a mate to do them, using siemens surface mount 10A hermetically sealed relays, reduce the switching caps to 600 mic because the new relays drew less current, and replace the switching trannies with 2n2222's which are pence from Maplin. Upping one of the R's (can't remember which without checking) reduces the current drawn dramatically too. You also need to replace the diode that sits across the power supply rails as it's almost always blown.

So far I've never heard of one of mine failing - and the original one is still in constant use in my ex #1458 with remote locking 7 years on.

NickT

Dan1986 Wrote:I know this is an old thread, but whats the latest with this? My lock module is a stock one at the moment, I saw this list of parts that Nick made http://www.deloreans.co.uk/forum/viewtopic.php?t=946 but that still uses a relay. What does everyone recommend doing to a stock module? And what is the reason for doing these updates?

This worked for me following this document:
ftp://dmcnews.com/pub/lockmod91.pdf

Relays quoted are 16A rated and the contact pads are larger.

The pin layout is exactly the same as the OEM relay so solders in perfectly with no trailing thin wires.

Replacement of transistors and the resistors reduce the standby current from 13mA to 1.3mA. (In the absence of any aftermarket equipment, the locking module is the largest current drain on the battery!)

Extra to the document, I added extra diode goes across each coil to prevent back emf. Any back EMF causies the contacts to 'chatter'. This chattering causes arcing and wears the relay pads out. Nothing wrong with relays. Industrial automation still uses relays in industrial panels. DC type relays have the diodes internally contained across the coil. In my 9 years of automation work I have only replaced 3 relays due to contact wear!

I didn't bother with those tranzorb things, wouldn't want a fire risk.

My rebuilt solenoid works fine and cost about £10 in parts and I gave it a good bench test before refitting it to my car.

Obviously a solid state solution would be an ideal if the standby current was just as low. £40 is a good price from Chris.

NickT.
Well my prototype is still in use in my old car, and as far as I know Ben, or Blimey, has not had any issues. The nice thing about my circuit is it fits into the OEM box and uses the stock DMC loom, the PCB is the same size and the wires connect in the same places as the stock module and does not use relays. Oh and I added 2 additional wires to allow a key less entry system to be added without cutting into the stock loom. I used this feature on Ben's car.
I did all the upgrades mentioned to my OEM module and I still found it locking and unlocking the doors one day so hence my re design with more modern components

The main cost is the PCB as its a double sided board and I did mean to make it a single layer board but not had the time. I know Richard Hutchinson mentioned he could produce single sided boards quite cheap, If Nick or Rich is interested I can send them the BOM and Gerber files for the benefit of the club.

I think I have enough bits to make one more module.

NickT

Thats very generous of you Chris considering the R&D you put into it.

I think it would be best to send to Rich (Rich) as he has more gear to probably make a production run on them Big Grin

I hardly get time to work on my own car these days Sad

NickT
Ive just popped the cover off mine:

[Image: lock.jpg]

It looks to me that its already been upgraded? Correct me if I'm wrong?

NickT

Looks stock but show a pic of the underside. This will show if any of the components have been re-soldered in the past.

NickT

NickT

The modified unit is on page 4 of the pdf document (the one with the white arrows on).
The modified transistors (BD679) in the middle of the board are more square.
Looking at the resistors values in your pic, yours are :

BROWN: 1
BLACK 0
RED 100 (MULTIPLIER)
ie 1000 ohms = 1kohm

Modified resistor value is 10k

BROWN: 1
BLACK: 0
ORANGE: 1000 (MULTIPLIER)

http://www.capgo.com/Resources/Measurem ... stors.html

I would say your lock module is OEM.

Hope this helps,

NickT
Thanks Nick your right. I just had a quick glance at the PDF and saw that my module looked like the modified one and not at all like the one at the beginning of the document, now realize they are just different modules. I will definitely upgrade my module in that case Big Grin

Cheers.
ChrisS Wrote:I think I have enough bits to make one more module.

Chris,

Please put me down for one

Best Regards
D