anyone got a late SAIC/NAC TF with OEM remote boot opener?

[Rob Bell]

Fair point! Something doesn't add up.

300mA is not very much in the way of current capacity - are we absolutely sure that is all the internal relays inside the Pektron box can handle? If this is what Paul (Technozen) tells us then I am sure it's right.

Confusing!

[fatbaldingoldgit]

External relays can switch 10 amps using much less than a 300ma trigger...so it's an easy thing to wire up..

[austingarages]

The boot release solenoid is a type that uses an electric motor inside with gearing etc.

Part number FUD100610 is a grey solenoid as in the picture and is a CDL type design for the Rover 200 / 25 / ZR tailgate. This is designed to have a reverse polarity for the locked and unlocked position.

FUG000030 looks exactly the same and was fitted to 25 / 45 / ZR / ZS from 2004 onwards with remote boot opening. At this stage no CDL was fitted to the tailgate / boot and the mechanical key to open the boot was also deleated. This solenoid had a a motor and gearing etc, but was designed to operate in one direction only when triggered, then return to a loose state to allow the spring loaded action of the latch to return the mechanism back.

I would say that all ten SCU internal relays will safely handle 25A, I think the 300ma figure is for the coil trigger side. But none of these relays handle the boot release anyway.

The SCU operates the external relay for remote boot release by creating an earth path for the external relay, the wiring diagram will look like this:

The earth for the solenoid can be connected to one of the existing black wires in the boot loom, this means only one cable needs to be routed into the boot loom for the solenoid.
The connector to the solenoid is a black 2 pin type, for reference it's the same as the one used for the horns.

I used the FUG000030 type solenoid when retrofitting this system to a 2004 TF back in 2008 (before MG Motor did!) and it worked very well:

The LE 500 is fully loaded otherwise, to the right of the fuses, are there any free relay positions in the block of 8 spaces? This may help asnswer where the official relay location is....

It's interesting that the MGF from day 1 was always designed with extra pressing on the underside of the boot lid to accept the different latch design for electric boot release, but was never implemented. The fitting instruction for the power hood let slip of this as there is an illustration of the console inlay with a boot release switch fitted...
http://www.mgfcar.de/powerhood/6_7.pdf

[fatbaldingoldgit]

The boot release solenoid is a type that uses an electric motor inside with gearing etc.

Part number FUD100610 is a grey solenoid as in the picture and is a CDL type design for the Rover 200 / 25 / ZR tailgate. This is designed to have a reverse polarity for the locked and unlocked position.

FUG000030 looks exactly the same and was fitted to 25 / 45 / ZR / ZS from 2004 onwards with remote boot opening. At this stage no CDL was fitted to the tailgate / boot and the mechanical key to open the boot was also deleated. This solenoid had a a motor and gearing etc, but was designed to operate in one direction only when triggered, then return to a loose state to allow the spring loaded action of the latch to return the mechanism back.

I would say that all ten SCU internal relays will safely handle 25A, I think the 300ma figure is for the coil trigger side. But none of these relays handle the boot release anyway.

The SCU operates the external relay for remote boot release by creating an earth path for the external relay, the wiring diagram will look like this:

The attachment image.jpg is no longer available

The earth for the solenoid can be connected to one of the existing black wires in the boot loom, this means only one cable needs to be routed into the boot loom for the solenoid.
The connector to the solenoid is a black 2 pin type, for reference it's the same as the one used for the horns.

I used the FUG000030 type solenoid when retrofitting this system to a 2004 TF back in 2008 (before MG Motor did!) and it worked very well:

The attachment image.jpg is no longer available

The LE 500 is fully loaded otherwise, to the right of the fuses, are there any free relay positions in the block of 8 spaces? This may help asnswer where the official relay location is....

It's interesting that the MGF from day 1 was always designed with extra pressing on the underside of the boot lid to accept the different latch design for electric boot release, but was never implemented. The fitting instruction for the power hood let slip of this as there is an illustration of the console inlay with a boot release switch fitted...
http://www.mgfcar.de/powerhood/6_7.pdf

This is really great information Nick..thank you..

re the internal SCU relays Paul's advice is:
".... the relay cannot draw more than 300mA, anything more than this will damage the driver IC in the SCU."..I don't know which of you is right, maybe both of you..not being an electronic expert..However, I'll be using an external relay as you did..

and I may also fit an internal button release so I don't need to use the 3rd fob button when the engine is running... I did create a wiring diagram yesterday which strangely enough is uncannily like your own..just need to get the fuses sorted in view of your and Paul's seemingly conflicting advice.

re your question " ...are there any free relay positions in the block of 8 spaces? This may help asnswer where the official relay location is...."..The answer is No, in my case..There are no free positions..Even the aircon relay positions are full...we investigated this a few posts back...so we are still no further forward locating where the original external relay is located...If I could get access to an 85th Anniversary to examine I might be able to find it but there are precious few of them and probably far fewer owners who would be prepared for me to take bits apart looking for it..Can't blame them really..

It's very interesting that the remote boot release idea was around even as far back as the original MGF days..

It looks like we have pretty much everything we need to re-create what you did back in 2008...unless you'll care to share even more details? For instance: did you modify the existing catch or use one from say the ZS?..presumably the appropriate TF catch is still available as a spare part?

As an aside..do you know if there is a workshop manual that covers the SAIC/NAC TFs...doesn't look like the MGOC stock one and we are not even sure if such a publication exists..would be good to get some official confirmation either way..

[fatbaldingoldgit]

just heard back from Rimmers re the boot latch.

LE500 boot latch is part number FQU100230
85th Anniversary and 135PS is 300000215

Rimmers don't hold stock of the 300000215 so the can't tell me what the difference is..

So it appears there is a difference..and hopefully that difference is the ability for the solenoid to connect to it..I might just take a punt and order one...

[Rob Bell]

Looks like some really good progress is being made

If I read what Nick's stated about the Pektron internal relays confirms my own thoughts: the internal relay should be adequate for the purpose of switching the lock release motor (it is not a solenoid). There is no extra external (to teh Pektron unit) relay for this purpose on cars fitted with the remote boot release. However fitting an extra relay is no big deal and could well add some useful functionality.

What is the age of that fitting instruction? I suspect it probably dates from around 1998/1999? Just curious: it may be that the boot release was a dealer-fit option, of which there were many including the powered softtop from around that era.

[fatbaldingoldgit]

Looks like some really good progress is being made

If I read what Nick's stated about the Pektron internal relays confirms my own thoughts: the internal relay should be adequate for the purpose of switching the lock release motor (it is not a solenoid). There is no extra external (to teh Pektron unit) relay for this purpose on cars fitted with the remote boot release. However fitting an extra relay is no big deal and could well add some useful functionality.

What is the age of that fitting instruction? I suspect it probably dates from around 1998/1999? Just curious: it may be that the boot release was a dealer-fit option, of which there were many including the powered softtop from around that era.

You may both be right so I've emailed Paul for his confirmation..I'm not comfortable embarking on a solution which might bugger my SCU if there is a lack of consensus on what the relays can handle..but as you say, we haven't been able to find an external one and adding a relay is no big deal..just need to find a convenient location close to the SCU..

I don't know how old that publication is..maybe Nick can advise?...

[fatbaldingoldgit]

Response from Paul re the question of SCU internal relays..

"First, the diagram you sent is spot on. The relay terminals 86 and 30 can be connected together and fed from the 10A fuse.

Yes, the relays used in the SCU can switch a 25 amp load however none of the internal SCU relays control the tailgate release, the solenoid is separate to the central locking.

If the solenoid is connected to Pin 9 the result will be a small puff of smoke and a destroyed TPIC6A595 driver IC .... I tried it in the early days of experimentation you don't want to do this to a good SCU!

The 300mA limit is what the TPIC6A595 IC can switch, the MAXIMUM continuous load is 350mA.
Pin 9 controls the ground side of a relay coil, the relay switches power to the solenoid, this is how MG-R designed and implemented it.

By all means quote this email, we don't need people complaining when they destroy their SCU!!"

Wiring diagram mentioned:

[fatbaldingoldgit]

Further information from Paul/Technozen:

Attached are the relevant extracts from the SCU design notes....Post them if it will convince people that a relay IS required.

BTW I did some further research regarding the location of the solenoid relay.

On the 45/ZS it is a standard "Yellow" relay and is fitted in its own holder on the centre console frame work, on the 25/ZR the same type of relay is used but fitted on a bracket above the bonnet release handle.

I spoke to a contact at XPart technical and he couldn't advise the location of the relay on the TF. Based on the other models I would expect it is fitted away from the fusebox.

[Rob Bell]

Paul's a star!

[austingarages]

FQU100230 is the standard latch carried over from Rover 200 / 25 / ZR / MGF.

300000215 will be different and have the extra lever and clip to attach the solenoid via a link rod. I suspect this is Chinesse reverse engineering hence the unique part number, no doubt similar if not identical to the MG Rover engineered latch FQR000070 fitted to 04MY ZR / ZS. The only bit you will have to engineer is the link rod to the solenoid because of the different boot lid without mounting plinth. When installed you will see the small pressing on the underside of the boot lid to clear the extra lever in the latch.

Here is the yellow relay mounted in said car:

The release switch with the dimmer relocated into the fuse box cover (as per power hood instructions):

Interestingly, no MGR product ever used the manual release switch idea, this was an engineered feature of the SCU and its wiring can only be found on the SCU design notes (which appears Paul also has). Maybe your car will only be the second with this feature! From a security point of view this switch works all the time, only disabled when the alarm is active. It's slighty Heath Robinson in operation in that the relay is only energised after the switch is released, if you're quick with pressing you won't even notice. It also does not have the feature of the remote handset button in that it is disabled after 5 mph, so you can open the boot at speed!

[fatbaldingoldgit]

More great info Nick..thank you.. ..I've ordered the modified latch...and will now see if I can get the OEM switch...and relay...

Is that yellow relay in a TF?..or a ZR/ZS...can't quite make out where it's located...I guess somewhere behind the SCU?

[talkingcars]

That is the left hand A pillar above the glove box in a TF.

I have a random wiring plug there in my mk1, wiring colours look similar although it isn't relay shaped.

[fatbaldingoldgit]

Following a very helpful post by Paul Madraszek over on .org I have confirmed that his findings are consistent with my LE500..

The wiring for the remote boot opening function is present in the LE500s. The fuse is F6 and the external relay is fitted in the unoccupied position in the relay block located behind the lining in the passenger side of the boot.

Slight different fitment of the relay block and the spare relay block is in the middle

The solenoid connection point is behind the boot light

I temporarily fitted the HRW relay to the remote boot relay location and it clicks when I press the 3rd button on my key fob once I refitted the 10amp F6..

I didn't manage to locate the manual switch connector under the armrest..if it is there at all..but I will take a girly look later once I've solved the remaining issues:

1. New boot lid or cobble up a solenoid fitting plate? - MGFNTFBITZ have some boot lids arriving from China in a couple of weeks. They are in primer so would enable me to replace my boot lid which has some nasty scratches with a lid that has the provision for the solenoid already present. Trying to justify the £100+ courier + spraying etc.
2. The flying lead from the white/red lead connector to the solenoid is missing..I can cobble one up from a ZR or ZS if I have the solenoid connector.

....continued on next post

[fatbaldingoldgit]

3. The boot latch needs to be either a real 85th Anniversary one with the tag for the solenoid to fix to or a cobbled up one with a tag welded on. I ordered a new 85th Anniversary latch from Rimmers in the expectation that it would have the tag but it doesn't. It's a different part number and one specifically for the 85th but is actually identical to the one already fitted to my LE500..Curious that..am following up with Rimmers.

.......

[Rob Bell]

Making good progress on this! You could braze an extra tag on to avoid excess heat if needed?

The two locks above appear practically identical?

[fatbaldingoldgit]

The two locks above appear practically identical?

They do don't they?..I couldn't find any difference in them at all..

FYI the left one is an LE500 latch-trunk lid part number FQU100230..the right one is an 85th Anniversary or 135 PS latch-trunk lid part number 300000215

[fatbaldingoldgit]

...and after discussion with Rimmers it looks like they have sent the wrong part in the right package..

This is what the 85th Anniversary latch looks like..

I've arranged to exchange them....

[austingarages]

Good work on locating the relay....

So LE500 boot release harness is fitted, need just a tiny link lead inside the boot lid, or the white connector cutting off and black one fitted in place.

For factory fit look with the standard boot lid you will need latch FQU100200 which is for a pre facelift Rover 400 / 45 / ZS, a later face lift 25 / ZR will also work too... This latch has the extra lever...

A custom made link rod to connect to the release solenoid.

Solenoid part number FUG000030.

This works well on our own TF.

I have noticed that there appears to be a dimensional tolerance with bracket on the factory version in that the screws are always left slightly loose to the solenoid, when tightened, the whole lot locks up, so not worth the effort of fitting a new boot lid.

[fatbaldingoldgit]

I'm cruising the breakers online at the moment to see if I can locate a bit of wire with the solenoid connector..The other end as you say is simply a case of cutting off the white connector and replacing with something else. That bit of wire isn't available as a spare part anymore according to Rimmers..

Implementing the manual release button will be simple too..just shorting pin 10 from C0661 on the SCU...

I see you have used a different latch mechanism and a custom link rod...I'm intending to connect the solenoid directly to the 300000215 latch and either make up a custom bracket or fitting an 85th Anniversary boot..I believe that the 85th didn't use a link rod..Is that correct?

Interesting your comments about the locking up when using the proper boot...

Fortunately FUG000030 seems to be readily available...and not shrouded in mist unlike some of the other components....