Generic keyless entry on SII?

(Jochen Glöckner) #1

Hallo everybody,

as you already know from “Door lock switch fallen apart” I’m going to replace the central door locking switch in my SII car. For all SIII owners: SII cars do not operate the power locks from the doors; instead you have to open the doors with a key, enter the car and then operate the power locks from a switch that is mounted at the location of your sunroof switch. In a way this switch on SII cars is very similar to the type of switch commonly used these days to permit passengers to lock up the cabin in unfriendly environments.

As much as I like the charm of the original setup - someone said that in the 1960s no gentlemen would not have opened their passengers’ doors first anyhow -, I’d prefer the opening and closing procedure of today as a matter of practicality. I also realised that the particular switch as used in SII cars should make it very simple to install an aftermarket remote control system as I’d only have to tap the remote signal receiver + relay into the wires available at the switch anyhow. And since I’ll replace the switch and have to remove the central console top anyhow to get access, I could just as well take the chance and install such a system right now and together with the new switch.

So my question goes whether any of you has gone through this, what type of system did you use, are there any pitfalls? A short search revealed that there are many systems around, most at very reasonable prices, but also typically adapted to much more advanced technology: To my (limited) understanding I’d only need permanent positive and negative for the triggering circuit of the relay and one negative for the main circuit and two positive out for lock and unlock. Did I miss something?

As always, all ideas are appreciated!


(Doug Dwyer) #2

I’ve installed several keyless entry systems on older Jags. You’re conclusion is fundamentally correct: the remote system is used to trigger the lock relays…although details will vary depending on which system you buy. Some are ‘positive triggering’ and others ‘negative triggering’…and some are switchable either way.

I say ‘relays’ under the assumption that the Series II has a lock and unlock relay like the Series IIIs and XJSs I’ve worked on. I’ve never worked on a Series II.

I’ve used “Bulldog” kits several times with good results. Although it’s been a few years, I found that Bulldog was one of the few that offered a very simple (and inexpensive) keyless entry kit of good quality. Most offer kits with 103 different whiz-bang features and capabilities that I wasn’t interested in and didn’t want to pay for.


(Aristides Balanos) #3


I bought one set from ebay, generic, simple and inexpensive… and works quite well.
It came with four actuators and a control unit.
I would suggest, if you go that way, to replace all four actuators.
The driver’s door actuator has five cables, i.e you will have to bring two more cables inside the door, or, if you install the control unit in the door as well, you will just need an extra +12V.
For the other three actuators you can use the existing wiring.
There are no extra relays involved, the main actuator just reverses the polarity of the pulse.
The control unit I got had also two extra cables that can be connected to a momentary switch to lock and unlock from inside the cabin, in your case your centre console switch.

Hope that helps,

(Doug Dwyer) #4

[quote=“Aristides1, post:3, topic:350762, full:true”]

I would suggest, if you go that way, to replace all four actuators.[/quote]

I’m afraid I don’t understand the rationale of that

The driver’s door actuator has five cables, i.e you will have to bring two more cables inside the door, or, if you install the control unit in the door as well, you will just need an extra +12V.
For the other three actuators you can use the existing wiring.
There are no extra relays involved, the main actuator just reverses the polarity of the pulse.[/quote]

I think we might be getting the different door lock systems confused…and I’m not familiar with the system used on the Series II.


I think what you’re describing is a keyless entry installation on a later Series III with central locking, possibly with the Kiekert lock motors.

As far as I know the Series II system is operated only by the console switch …as opposed to central locking which is operated by locking/unlocking the front door(s) with the key. I may be wrong. But, in any case…

If the Series II has the two lock relays there is no reason to add/change actuators nor run any wiring into the doors. The keyless entry system can be used to operate the relays. For that matter, it might be possible to wire the keyless entry into the existing console switch…again without going into the door itself. In this case the keyless system just replicates the function of the console switch.

The control unit I got had also two extra cables that can be connected to a momentary switch to lock and unlock from inside the cabin, in your case your centre console switch. [/quote]

Which would be useful


(Jochen Glöckner) #5

Thanks Doug and Aristide,

indeed, Doug describes the function of the central switch correctly. I don’t want to change any of the actuators nor put in any more wires. There is plenty of space in the central console to put in the controller. My idea is basically to have it fake the signal of the original switch by simply mounting U-connectors to the spade connectors and then simply feeding the lock/unlock signal of the controller in lieu of the same signal given by the rocker switch into the original wires. Depending on how the remote signal is transmitted there might be a second issue related to the mounting point of the receiver. If it is radio controlled there shouldn’t be a problem though.

I checked that Bulldog system, you recommended, Doug, but couldn’t find any installation instructions. The picture looks a bit complicated though.

Thanks again and have a good night


(Frank Andersen) #6

The SII has 4 solenoids in the doors, Jochen, and probably one for the boot - directly operated by the switch…

Most available aftermarket central and remote control systems use motors - as does indeed the later SIII, the early versions using solenoids. The wiring to the doors and boot are identical, two wires - but the motor systems use polarity reversal. But with the solenoids; only one wire is powered for ‘lock’ the other powered for unlock, the solenoids having a common ground for the two coils used. The aftermarket systems, using motors, are not a straight in fit…

To elaborate; as the central locking system was introduced, the driver’s door solenoid (or motor) was replaced with a door key operated control unit. The control unit for the ‘solenoid’ set-up sent a brief power pulse to one of two relays, one ‘lock’ and one ‘unlock’ relay through the appropriate wire. With the ‘motor’ system; the control unit alters polarity with ‘lock’ and ‘unlock’ motion of the key - the relays are omitted, and the control unit drives the motors directly.

This is also the case for the aftermarket central/remote systems - however, with remote systems the control unit is a combined motor/control unit. When the remote is used, a signal is sent to the driver’s door motor, which runs the motor - which then activate the control unit to operate the door/boot as if the door key was used…

With a remote set-up you don’t really need the key lock control unit - it could operate the existing door solenoid. A malfunctioning remote would still allow the door key to unlock the door for entry. The problem you are facing, unless a remote designed to operate solenoid can be sourced, is to convert the polarity change to a ‘single wire’ power delivery for use for solenoids…

I ‘think’ it has been done, and it is possible - but rather complicated. The reason being that there is no ‘end-stop’ power break to solenoid, or motor, motions. For this reason; the power pulse to the door units, solenoid or motors, is brief - just long enough to ensure full ‘lock’ or ‘unlock’ travel. converting to ‘single wire’ operation is easy, using relays - but ensuring that power is only briefly applied is the tricky bit. You may get response from someone who has done it - it is simpler than figuring out how, and I have no immediate solution. You could of curse convert from solenoids to aftermarket motors; apart from the ‘mechanical’ work involved to fit and align the motors - and extra wires also fitted to the driver’s door for the remote operation. Of course, with cost no concern; you can fit the Kiekert motor system from an xj40 - it will fit right in as replacement for the solenids, and is prepared for remote operation…:slight_smile:

As Doug also says, a ‘central module’ needs to operate the same way as the switch - however, with the switch it is up to the driver to avoid continuous power to the solenoid by timely release of the switch. The solenoids are very robust and can stand some extended application of power - however, they are no impervious; prolonged application will burn them. For this reason, I assume that protection is provided by thermal fuses - and that no driver would use the switch witlessly! With motors; they will burn almost instantly if power is applied after they have reached the end of their travel…

xj6 85 Sov Europe (UK/NZ)

(Aristides Balanos) #7

Yes indeed Doug, my experience comes from an SIII, I did not know that the SII had relays, sorry for that…
The rationale of changing all the actuators was that my system stooped working and I had to also replace the drivers door actuator, and then, the after-market system had a very short pulse witch was not enough to operate the original actuators properly.

Anyhow, the presence of relays simplifies the installation, I guess you just need to feed the pulse at the relays.

Frank, you have a point there, the system I got operates exactly like that, however I have seen others that have a different configuration.

Yes, they are radio controlled.
I have mounted the receiver and antenna inside the car and had no problem, I was actually surprised, I can unlock the car from 10 meters away…!


(Frank Andersen) #8

The central point here is that the solenoids use ‘one-wire at a time’, Jochen - not polarity reversal used with ‘two-wire’ operation common to central/remote systems…

As no relays were fitted before the key operated central lock system was introduced; converting to remote requires two relays. - as indeed if you want the conventional key central locking system. The latter also requires the driver’s door solenoid be replaced with a solenoid control unit…

With a remote, driver’s door solenoid is retained - and only the remote receiver is required. The two wires normally going to the motor control unit instead goes to the relays. Each of the wires must be doubled through a connector - two wires to each relay. Diodes at each relay, with ‘opposite’ direction will ensure that current will only flow through one of the relays at a time as the remote switches polarity for ‘lock/unlock’. The brief pulse delivered by the remote receiver will operate the relays for the appropriate time…

You need fused constant power feed to the relays - the ‘in’ wire of the consol lock switch will do. The ‘out’ wires of the switch to the door and boot solenoid wires connected to the relays. To get the correct lock/unlock response with the remote, some experimenting will clarify connections. The relays may be placed to taste, but behind the A-pillar cover is the usual place - together with the remote receiver…

This set-up will not centrally unlock the doors with the door key, but the door key will of course unlock the door in case of
system/power failure, of course…

xj6 85 Sov Europe (UK/NZ)

(davelloyd) #9

I have a Series 2 and I intend to do the same thing as you’re describing.

From what I remember when looking into this, when you press the switch forward it it connects the two front terminals and locks the doors. When you press it backwards it connects the two rear terminals and unlocks the doors.

The idea I had was to add “u” connectors, as you describe and then connect them to remotely operated relays.

I searched and found this -

You can download the user manual from there and the unit contains two relays that are operated by two buttons on the remote switch. I also noticed that the relays can be set to “latch” or “momentary” while the buttons on the remote are pressed.

I have not done this yet but it seems to me that it should work.

My only reservation is the amount of current across the switch terminals when it is operated and whether the relays in the remote unit would handle the current. I never got as far as measuring what that current is.

I must emphasize that this is something I am toying with doing and I am not an auto electrician :wink:

Something to think about though.


(Jochen Glöckner) #10

Gorgeous, Dave,

call it parallel invention or similar needs calling for similar solutions! In fact we’ve come to exactly the same point:

  • As regards the switch : Cf my postings relating to “Door lock switch fallen apart”. Yes, this is how the switch operates. + is led into the switch via the brown/blue wire (#4) and leaves the switch either not at all (centre position) or up resp. down (orange/green, orange/red; ## 1, 6). It is not a pulse switch, but lets current flow as long as it is depressed. The system relies on the spring pressure inside the switch, moving it to neutral, once the pressure is gone, and on the lack of motivation to keep depressing a switch once function has been achieved. Power on orange/green resp. orange/red in turn operates the two door lock solenoid relays situated right in front of the rear seat bench.

  • As regards the operation: The most simple way to operate these relays seems to be a two-channel RC switch. A full remote control keyless entry system is way over the top. OTOH, I think you need two independent channels to operate both relays. Two other things I found out, just like you did: (a) the RC switch needs at least to offer a possibility to choose between switched and momentary operation. (b) the RC switch must be adapted to 12 V DC, as it is fed from the car’s power net. The capacity of the switches should be sufficient as they only have to switch the trigger circuit of the original relays.

I found such systems from around 16 EUR up to 75 EUR. As most of the switches available online seem to be identical products from some Chinese factories and customers’ complaints abound I’m a bit reluctant to order one without a reputable local customer support. Haven’t yet made up my mind, but one of the products I found is

  • As regards installation: I’d get three V-type female spade connectors as the far right in this picture
    and use them on the original switch to re-connect the original three wires and diverge three more blue/brown power wires and each one orange/green and orange/red wire. One power wire then feeds the RC switch power, added by a ground easy to be found underneath the centre console. The other two power wires feed into the two channels (in) and the two orange/green and orange/red wires feed into the two channels (out). At least this was my plan, but I’m no auto-electrician either. Maybe our pros chime in …

Good luck


(davelloyd) #11


It’s been a long time since I looked at the switch so all I can remember is that I thought this remote control unit would work.

The manufacturer’s website is here -

If you look on there you can download the datasheet and see what you think.

There is also a list of distributors and one of them called Premier Farnell seem to have branches all over Europe.

The relays on the control unit are rated at 5 amps at 230 volts and from what I can remember from school that should mean they will handle 95 amps at 12 volts but I could be way wrong there!


(Robert Wilkinson) #12

You’re calculating watts, which is meaningless because the switch isn’t the “load” like a heating element or light bulb. Actually, for the contacts of a given relay, the AC volts and amps rating cannot be used to predict it’s DC volts and amps rating.

A major difference is the “break” of the current when the relay opens–similar to ignition points. With DC, there tends to be an arc that persists for a while, particularly if the load is inductive. With AC, the voltage disappears (the sine wave passes through zero) 100 or 120 times per second, which tends to stop the arc. Obviously, the higher the voltage, the more problematic the arc in considering switch ratings.

The “make” of the contacts is similar for AC and DC, as is the resistive heating of the entire circuit within the switch when the contacts are closed. Both of these considerations determine a maximum current rating, which is independent of voltage. Similarly, the insulation of the switch helps determine the maximum voltage rating, along with the arcing mentioned above.

A general rule, if specs aren’t provided, is that the DC current rating is significantly less for higher voltages, but for voltages below 30V, the DC current rating is about the same as the AC rating given for higher voltages. IMHO.

(Frank Andersen) #13

It might be just what the doctor ordered, Dave…

…particularly the ‘momentary’ feature - which is pertinent for both solenoid and motor operations. The stated capacity of the ‘QS’ relays may be adequate to run 5 solenoids directly - but Bob’s points are very pertinent. The current drawn by 5 solenoids will be around 12A+ while moving, but current will be higher for continuous engagement - hence the solenoid system is protected by a thermal fuse. However, there is no mention of fusing in the ‘QS’ unit - though an in-line fuse could be used; the thermal fuse may be inadequate to protect the unit itself…

Until Bob’s concerns are addressed, or it is somehow clarified that the ‘QS’ system can handle the solenoid load directly, (12V at 12A+) - external relays should be used, the ‘QS’ operating external ‘lock/unlock’ relays. This is particularly relevant for the SI remote setup - while there is also an added complication for the SII. Which, if it has the key operated central locking, already have the external relays; there is no driver’s door solenoid - which therefore will not open by the remote…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Ie, the SII

(davelloyd) #14

Thanks for the info on the current rating. It’s been a long time since I was at school. I was obviously talking a load of rubbish there :smile:


What I can say is that on my Series 2 there is no boot solenoid, just the 4 solenoids in the doors. Opening either the driver’s or passenger’s door with the key does not operate the central locking. The only way to utilise the central locking is via the switch on the central console.

It seems to me that it would be a good idea to measure the current at the switch when it is operated and contact the manufacturer to see if the “QS” unit would handle the load. If not, then the unit could maybe set up to operate two separate relays of sufficient capacity to handle the load, as you suggest.

I don’t really understand how the system works in detail, but as the system is protected by a thermal fuse then when the remote relays were operated by the remote then they would be protected by the thermal fuse as the system wouldn’t “know” if the switch had been pressed or the relays operated, just that the relavant wires had been connected?

(Doug Dwyer) #15

Power on orange/green resp. orange/red in turn operates the two door lock solenoid relays situated right in front of the rear seat bench.[/quote]

Until now I wasn’t 100% sure that the Series II used lock relays.

So, the console switch operates the lock relays, and the lock relays carry the heavy load of the lock solenoids. Good. The installation of the remote entry system should be easy…although this conversation has become a bit complex :slight_smile:

A typical automotive relay (such as a door lock relay) draws way less than 1 amp. Usually more like 1/10th of an amp. Maybe a wee it more for the big ol’ clunky relays used by Jaguar, I dunno. But, I’d say 1 amp or less goes thru the console switch

All the automotive RKE and/or security systems I’ve installed have built-in relays for the door lock functions and have worked perfectly well for triggering the existing factory installed lock relays. I want to say these built-in relays are generally rated for 5 amps…but I’m not sure why that number comes to mind. Must’ve read it somewhere. But, in any case, they are designed to accommodate the current draw of typical automotive relays.

Optional functions, where offered (blinking lights, horn sounding, window closing etc), require additional relays to be added. Or, if (for whatever reason) the remote unit is being asked to directly power-up a lock solenoid (as opposed to triggering a relay), an additional relay must be added.

Generic remote systems…not specifically designed with automotive use in mind…might be a different story, as mentioned


(Jochen Glöckner) #16

Thanks everybody!

In fact the SII cars have relays before the solenoids. They appear in the wiring pattern as # 258, are marked in the scheme at 86-43 and in the ROM at 86-25-33. I even happened to see them once:-)

You’re confirming my impression that the mere trigger circuit load of such a relay should be worlds apart from the typical amperage of these RC switches that are typically advertised with something from 3 to 10 A. Of course, the best thing would be to put in a meter, but for the moment I’m happy to have reinstalled everything.

Best regards


(Frank Andersen) #17

Measuring the current drawn is a good idea, Dave - to verify that "QS’ unit can carry the load directly…

When measuring; do not hold the switch longer than necessary to get a reading - as said; the current drawn while the solenoids are moving is lower than when they reach the full travel. With only 4 solenoids the current will likely still approach, and may still exceed 10A. Most digital ammeters has a ‘10A’ setting - which may be sufficient for a reading…

The two-channel ‘QS’ likely has two output wires - one powered in ‘lock’ the other in ‘unlock’. The powered wires to be connected to the respective ‘lock’, orange/green, and ‘unlock’, orange/red, car wiring - if the "QS’ can handle it directly. If not; external relays will solve that problem…

The rating of the thermal fuse protecting the solenoids is unknown - but is in any case rather slow reacting. Unless the "QS’ can handle current up to the thermal fuse limit, the latter cannot effectively protect the ‘QS’. With external relays, the current required to operate relays are, as Doug says, usually in the mA range, and only a separate 2A fuse, or thereabout, will be required to operate the ‘QS’ itself and the relays. The power wire to the switch can then be connected to the relays to operate the solenoids, using the protection of the thermal fuse for the solenoids…

In any case; it should be a fairly straight forward conversion - the ‘QS’ being the simplest, in either alternative. The ‘run of the mill’ remotes will require external relays and diodes…

xj6 85 Sov Europe (UK/NZ)

(davelloyd) #18


I do intend to see if I can make this work.

This is where I am with the car so it may be a while…


(Frank Andersen) #19

It’ll work, Dave…

To belabour a point; the solenoids are two wire coils connected together with a common ground - the car wires are connected at the other end of each coil. As power is applied to one coil at a time, it is magnetized and attracts the moving iron core inside, which is connected to the operating rods locking and unlocking depending on which coil is energized…

The main reason relays was introduced with the key operated central locking was that the controller in the driver’s door used capacitor discharge - which was quite insufficient for solenoid operation, but gives the necessary short impulse to the relay. Whatever system you select; this is the very important feature - it must give a short pulse.

Used as a garage door opener, a remote will likely power the garage doors continuously while opening or closing - power is then switched off by endstop limiters. This feature is absent on ‘our’ central locking system whether solenoids or motors - so the brief pulse is a must.

Traditionally, we say that the solenoid system cannot operate with power reversal, but it may not be the whole truth - if there is ample DC power from the remote unit, power reversal may work. This is not the case for traditional remotes - they basically can power only one motor. However, the ‘QS’ is described as having built-in relays which will likely do the ‘single’ power wire trick - and seemingly a necessary ‘short’ pulse option…

May point here is to allow you to evaluate other options if the ‘QS’ proves unsatisfactory…:slight_smile:

xj6 85 Sov Europe |(UK/NZ)

(davelloyd) #20


I finally got round to doing this and it works!

I bought a Velleman 2 channel remote which is programmable to operate the unit’s internal relays for different time delays.

I tested the current across the two contacts on the console switch and the current rose to 7 amps and then the thermal breaker tripped.

I was unable to determine if the relays in the Velleman unit would handle the 7 amp current so I wired it to operate two separate 30 amp relays.

I chose the 5 sec delay on the unit and it all works fine but the only thing of note is that the 5 sec delay is timed AFTER you release the button on the transmitter. If you hold the button down for any longer than needed, say 20 seconds, the contacts on the console switch remain connected and eventually the thermal breaker will trip, which is exactly the same as if the switch itself was held down for too long.

I have some ideas to make the secondary relay accept a continuous input and produce a momentary output so that no matter how long you hold the transmitter button for, it it only gives a momentary pulse long enough to operate the locks. I believe I can do this using a small capacitor, resistor and diode to the secondary relay. If anyone more experienced than me with electronics I would be grateful for any advice.

Just need to work out how to get it to flash the lights when the remote is operated…