Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 M3W Electrical Gremlins strike

Hi Alister,
No the box with four relays in is not on the wiring diagram. The diagram is far from a comprehensive one with several wires not following what it shows in practice. I am certain that sidelights/headlights power enters the box from the h/lt switch. all the relays now seem to work. the headlight stalk switch when pushed away from you activates the solenoid in the box but the mode is stuck on high beam even with sidelights on. The search for wire crossovers continues.Thanks for your help with eliminating the Indicator Module.
rgds
Ian

Thanks for the update. I wonder if a relay contacts are stuck in the Make state? The coil will still make the clicking noises but current will always flow through the welded contact pair. Those relays are quite hefty so it is not likely, but you never know!

If this box can be connected to the loom with its cover removed then it may be worth soldering some LEDs temporarily on the coils and contacts to ground. That would be useful. Of course if you use normal LEDs they will need a series current-limiting resistor each.

Let me know if you wish to try that and I will chuck in, FOC, some LEDs and resistors with your TSM package.

The relay that deals with the main beam change makes a clicking noise but has no effect. i changed the relay for a new one to no avail.
Because there are link diodes joining relay to relay I feel one of them failing could cause reverse flow but have no idea how to test the diodes etc
ian

Are you able to get to the relay terminals and either solder LEDs on or maybe slip off each terminal wire one at a time and slide a wire into the crimp terminal and then slide it back onto the relay?
Can you make a drawing of the wiring, relays and diodes?

Hi Alister ( and anyone else interested)
Late yesterday (* Friday) I finally found the cause of the problems.
The issue had been sudden loss of side lights/headlights ( ALL rear lights worked)
However when I turned the headlights on the fuel pump/ignition powered up.
The engine started and ran fine.
The fault remained elusive all week with all relays checking out etc.
I then decided to test all earth connections at plug end. Having already found some of the many earth connections to the chassis to be slightly loose ( vibration?)
I found some voltage within one section of the earths in the loom and finally traced back to a small plug that had "The Fuzz" growing on two connections a live and an earth. This connected the two and caused voltage feedback to the pump or vice versa. I even think I found the reason for "The Fuzz" which was caused by moisture. More and pictures later as I put everything back together.
Ian

Well done, Ian!
I have commented on your Fuzz, and this morning's VSS test, under Let's Build a Better...

Earlier in the week I posted about the strange electrical problem I was having with my five speeder. No sidelights, no headlights but sidelight/headlight warning lights lit ! but turning the headlights on activated the fuel pump/ignition. First suspect was the "Module" in the circuit but Guru Alister took it apart and declared it fit for purpose.
Anyhow, four days later and with a bad back from bending over the MOG checking wiring circuits etc I found the fault in a small plug in in the loom.
After three days of checking relays connections and multi plugs with gallons of tea drunk too I got nowhere. a concerted effort with a magnifying glass to see much closer than my aged vision allows led me to one of the two plugs on the back of the speedo. The smaller of the two plugs had a powdery growth spread between a live and an earth. This live wire was a feed to the Dash Display sidelight/headlight warning lights A test of the earth with my meter revealed a voltage track via this earth. After cleaning up and spraying with a PTFE based lubricant the fault magically disappeared. A chat with Alister confirmed it likely to be Copper Sulphate which would lead to the problems I had been having. looking more closely into why the two wires had this corrosion on them it became apparent that any water that found its way down the base of the little windscreens where they are siliconed in would drop behind the dash. Morgan have quite rightly fitted a drip tray to deflect any water away from the instruments but my tests showed it ran along then some found its way onto the speedo/rev counter plugs. Dampness causes the type of corrosion I found on the terminals. All plugs were sprayed with a PTFE/Waterproofing agent ( GT85) and an extra hood of gaffer tape over the plugs into both units. Clearly just a simple fault plays havoc and causes voltage feedback through the loom. I strongly recommend similar action for older "used" as intended in all weathers Morgans.
It is a shame that Morgan only provide a Wiring Harness Diagram and not a full Wiring Diagram with each circuit explained.
I also felt that it might be a good idea to make a cover to fit directly over the fusebox in addition to the assembly that Morgan use as a fuse cover. Doubly sure that no water can find it's way into the circuit again. Another potential problem on my 2012 was the wires from the Ignition key fouled the steering rod and each time the wheel was turned the joint fouled the main wires and evidence was there that they were being scraped away. So I put convoluted tube over the wires and cable tied them away a little, playing safe again !
Ian Parkinson
Cables covered and cable tied away.

Main Ign wires foul steering

Box not shown on Loom Diagram with four relays in. ( Lighting controls)

Rear of Speedo .Plug at 3, o clock had fault.

Rear access panel removed.

At Carbuilder they may have fuse covers to avoid the dust nest.