Talk Morgan Forums Thread Like Summary - Workshop Note: Immobiliser C.2016...........

Last Wednesday I went to start the Plus 4 and the immobiliser light didn't go off when I clicked the ignition on. I knew the battery could do with a charge, so I charged it up overnight. The following day it started normally so I put this down to voltage sensitivity.

Yesterday, I wanted to fill the tank,so jumped in expecting a start, and the immobiliser light didn't go out.

So I removed the cowl to examine the sensor ring which surrounds the ignition lock barrel. This ring has a scientific name but rather than guess I'll call it the sensor ring. It detects the sensor which is buried inside the plastic part of the key. If you look carefully on the metal key side of the black plastic the location of the key sensor is visible as a filled hole.

The sensor ring around the lock barrel is secured by a neoprene spacer. Almost like I've been there before! I moved the sensor ring outwards, and the car started. It was a bit nail biting at the filling station but it started OK.

When we got back home I tried again and it wouldn't start............

So I consulted my Guru..........

The distance between the key and the detector ring is critical to probably within 1mm or less.

He's had a couple of Morgans in recently in the "18 months old to two years old range" with this issue.

The trick is to get the detector ring as close as possible to the key handle...............

This is how it comes from the Factory. The lock barrel is wrapped with standard density self adhesive neoprene. Around that to prevent the ring slipping inwards is a thin strip of neoprene. If your cowl is leather wrapped, the leather adds additional distance between the ring and key.



The next image is a bit clearer. The wiring from the sensor is a bit tight, but can be eased out from the cable tie buried under the dashboard.



The black plastic cover pulls off the lock barrel which makes removing the original neoprene much easier.........
The detector ring is upper left.



This is the DW solution. High density neoprene and with the securing ring held with a cable tie.
Refitting the cowl is tedious. I reduced the overlap of leather to try and reduce the thickness around the lock barrel. First time didn't work so I had to go back in and space the ring a little further out at the top.



If you ever get caught where the immobiliser light won't go out, wipe the black plastic part of the key around the lock barrel, and you'll have about twenty seconds to insert the key and start the engine after the light goes out!!!

Three starts later it looks promising, but who knows!!

Hello from Hamburg,
with big interest I read your posts ref. immobilizer issue`s. We had the same problems on many cars.
Mainly on those new Plus 4 GDI models. We made lots of attempts to find out and I think we could sort out those disarming problems on nearly
all customers cars with that problem. I can confirm that the battery voltage is one of the points which do cause those disarming problems.
The more the voltage goes down, the more the problem can appear.
Yes, we have been busy with the reluctor ring on the ignition lock as well and did move it as far as possible towards the ignition key.
In addition we did check all earthing points as well. All this couldn`t fully cure the problems.
So we took a look to the ignition key itself. The newer immobilizer shows a red insert on the ignition keys.
There is a very small hole on the downside on the key, on that side you put it into the ignition lock. When you take a very small pin or bigger needle you can push that insert out of the key.
The small glass transponder sits in the read insert. Unfortunately the insert does not offer to place the transponder as much as possible towards the reluctor ring.
So we modify the insert itself, I cut away the big end of the insert which shows to the reluctor ring. In addition I carefully drilled the hole for the insert a bit deeper.
Those modifications do move the transponder inside the key around 5mm closer to the reluctor ring.
After this modification we had no more starting issue`s on those cars.
I haven`t got such a key in at the moment, for to show you via some pictures how we did do all that.
So after all you did try to solve that problem, maybe it`s worth to give it a try..

Regards Frank from Morgan Park

Dave my car is 2014 plus 4 and been having the same problems ,on and off for ages, after I leather covered the cowl. So now I have done what you have now done and made the hole in the cowl and leather the same size as the ring,and moved the ring to the edge of the cowl ,and no problems since,so it should work.duncan ( parked next to you at Mogfest)

I might be wrong but it may be you are actually compensating for a different fault. The path taken, chasing the distance between the key & the sensor doesn't explain why it was working - then it wasnt. & now its iffy, If the distance was so crucial you would have experianced issues since day one.

These things( Key sensoring immobilisers) do have issues when the battery voltage is low. so i would start by checking the voltage at the battery , then the voltage at the sensor down stream of the soldered connection (Possible dry soldered joint).Im not familiar with your cars wiring , however if the voltage is ok , the next step would be to check the impedance to the Immobiliser Module.& so on through the circuit .

It may be there is a high resistance in the circuit which isnt apparent during the dry balmy days of summer - but come winter the.? This is exactly why people suddenly get battery issues in the winter .