Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Dreaded PCB Stikes Again

Sounds like a good result and reasonable compromise to just use fan speed 1

To find someone prepared to have a look at a repair nowadays is very lucky, and at £36 is amazing

Thanks Jon

Richard is a great guy and while he's predominantly a PC engineer he will fix anything with electronics, when I dropped the Morgan PCB off he didn't bat an eyelid and went straight into diagnosing the fault, along with all the PC stuff he also had an electric golf cart and a Lamborghini dash screen in for repair.

He's also very fair with his pricing, what he did for me and the results his repair gave was definitely well worth the £36, being so close to me helps too but I'm sure he'll take on repairs sent by post.

RL Supplies, Unit 24,
Peerglow Industrial Estate, Olds Approach,
Watford, Hertfordshire,
WD18 9SR.

https://www.rlsupplies.co.uk/he

Dave, many thanks for the contact info, he's now in my database of 'just in case' Mogs/electronics/dash modules

Dave, just looking over this thread whilst munching my cornflakes. Is that heater quadrant snagging the ribbon? Might be worth checking that 12 way IDC when its next out.
(3mins 30secs in)

Hi Rog,

The answer is yes, or rather I should say the heater quadrant was snagging the ribbon, it looks like the screen print you show was taken from the video I recorded in my office shortly after I'd removed the dash module, and I believe I'd disconnected the ribbon at the time which is why it looks like it does in the above image.

To solve any posibility of the ribbon catching the quadrant I used a cable tie around the plastic removable PCB back cover and through the ribbon loop itself which holds it neatly clear of everything but without stressing the ribbon, all connections were carefully checked on reassembly and I also made sure the cable tie safely cleared all components on the board side, sorry no photo to show this but hopefully my description makes sense to a seasoned PCB expert like yourself?

While I have for some reason temporarily lost the hazards I'm hopeful this will be a straightforward fix, and when I do pull the dash down again to look into this I plan to fabricate a removable switch stop so for the time being I physically can't go to fan speed two by accident. I’d recruit Richard’s services again to look into the speed two issue, however, in reality the first fan speed is more than powerful enough, the Morgan heater is furnace hot so I really only need fan speed one which has proved more than powerful enough to keep me toasty warm even with the roof down in winter.

One thing I've failed to cover in this post is the fantastic support I've received from Roger, his technical knowledge and words of encouragement by email have been absolutely invaluable!

Thank you Roger

These cars have their little faults but in many ways for me this is all part of the ownership experience, call me a masochist but secretly enjoy such challenges. In this respect owning a Morgan is very much like owning a TVR as I did for 12 years, the self help community that exists around such cars is a wonderful thing we should all celebrate and give value to.

Clearly there are a number of approaches to solving the PCB problem and no doubt Roger's remote relay and toggle switch mod is one of the best, I think I can speak for us all when I express my gratitude for the time he’s invested in comprehensively explaining his solution in his excellent post. On this occasion I decided to go down the repair route which has proved mostly successful, and with the hazards sorted I will consider my PCB fixed with everything important working as it should, not bad for £36 and a couple of leisurely weekends work.

However, for me the ongoing reliability of this PCB remains in question so if it fails again I'll probably have one more go at a repair, with a view to fitting a Luigi Borghi analogue wired dash module if it then fails for a third time. The Luigi Borghi analogue wired dash completely deletes the PCB which to my mind has to make it the ultimate solution, sure it does need fitting at Luigi’s Morgan dealership in Milan but as Monty is a keeper I just view this as a great excuse for another continental Morgan road trip.

Perfect fix Dave

Shame they weren’t built that way. It’s a bit of a watch point for anybody with this ‘arrangement’

It's like this, just with the cable tie also passing through the ribbon loop, I very gently encouraged it to go in that direction without making the ribbon go past its natural existing curvature.



To be clear, the ribbon isn't pinned down tight against the PCB cover, I'm using the cable tie loop more as a loose anchor point to ensure the ribbon lies in such a way as it can't touch the quadrant throughout its full range of movement.

All highly sophisticated stuff

A quick question for Roger/all regarding my missing hazards if I may



I note in addition to being switches, the four above switches are also used as locating dowels for the board itself, and with the whole dreadful sandwich clamped together using the four corresponding plastic twist pins I've circled below:



Now, if we get in close on the back of one of these switches these look like the switch contacts to me.



I wonder if my loss of hazards is simply due to me failing to push the hazard switch home firmly enough, and or I failed to ensure the twist pin wasn't located properly so one of the switch contacts isn't being pulled tightly against its corresponding supply terminal?



Has anyone else suffered such an issue and traced it to poor switch location, or weak PCB to switch clamping force due to a badly engaged twist pin?

Maybe, but I don’t thinks so. The twist pins cannot really be twisted until the switch actuator and body are firmly ‘snicked’ together. It quite a clever little switch assembly. Also the other 3 switches would tend to pull the forth into position, unless all four were not correctly assembled. So never say never….



Actually looking at your last video I couldn’t see the hazard switch positively ‘latch in’ as it should? Maybe I just couldn’t see it on the video but the button will latch in 2/3mm. Worth going and checking. If it doesn’t latch in, there’s something wrong.

Failing that, maybe a bit of electrical probing? The first check might be to check pin.1 on the PCB’s 12 way Molex has 12v with the ignition off. Pin.1 should always have 12v and goes directly back to fuse.6 under the bonnet. The hazards are on a different fused circuit to the indicators as they have to work with the ignition off. If the power is getting to the PCB then perhaps carefully check that pin.14 on the microcontroller has it’s 5v supply and the regulator is working. The micro should also be alive with the ignition off waiting for a switch input. Atleast that's my understanding and if you get that far it will narrow things down, a bit, maybe

Thanks Rog,

You could be on to something mate

I'll double check my depth of hazard switch latching and compare this with the other working switches, I also need to check that my cable tie ribbon anchor point I've looped around the removable PCB cover is not interfering with the microcontroller and or pin 14 in some way?

From above:



And from below:



Perhaps my cable tie is just physically stopping the hazard switch from pulling down correctly?

Ah the joy, it does seem I need to drop the dash again to at least study these possible causes for my loss of hazards, hopefully it's something simple and easy to fix?