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Joined: Apr 2024
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Just Getting Started
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OP
Just Getting Started
Joined: Apr 2024
Posts: 51 Likes: 10 |
Hi All My little tale of woe that might be of use to others. 1999 Morgan two seater 4/4 fitted with Ford Zetec 1.8 silver top petrol engine. Car was running fine when last used then left in the garage during December and the first two weeks of January. Nice day arrived let's go for a ride. Car would not start. Checked fuel pressure that was normal. Checked for sparks no sparks cylinders 1 and 2. The coil pack fitted to this car sparks cylinders in pairs, cylinders 1 and 3 together then 2 and 4 together, this is the so-called wasted spark arrangement. It works because only one of the two sparked cylinders is on a compression stroke the other is on exhaust. With 1 and 2 not sparking fault must be common to both pairs. Checked the 12 volt supply to the coil pack and this was missing. This is the common power feed for the two primary windings inside the coil pack. Connected a temporary 12 volt feed to this point and car started immediately. After many hours of tedious wire tracing, found the fault to be a dislodged female pin, pin 1 in a 12 way connector located under the bonnet, drivers side (UK) near the fuel filter and tool storage box see photo below. This dislodged pin was not obvious. The giveaway was the small yellow ribbed rubber seal you can see on the wire. This seal pushes into the connector housing behind the pin and should be well inside the housing, but on this pin (pin 1) it was protruding slightly. If you look closely at the photo you can see there is another pin with a black wire attached three holes down (pin 4) that has the yellow seal protruding just like it was on pin 1. This pin (pin 4) was also dislodged but not far enough back to become disconnected. The pins have a couple of barbs that should stop the pin from coming out of the connector housing once they have been pushed home into the housing. These barbs needed a slight tweak to make the pin latch properly into the housing. I can find no wiring details of this car so I decided to try and trace the rest of the wires passing through this connector and draw a diagram, see below. Some of these wires lead to a 6 way connector located near the throttle body. Now the disclaimer. You're welcome to use the diagram but at your own risk. I have traced these wires using continuity and voltage measurements only. Also I have not traced all of these wires end to end, in particular those that are shown connected to the ECU (the ECU on this car is very difficult to get at). For the ECU pin numbers I used an engine wiring diagram contained in the Haynes manual for the Ford Escort and Orion 1990 to 2000 manual number 1737. The diagram is on page 12.52. The wire colours on the Morgan for all the injectors, sensors and actuators match this Haynes diagram so I am pretty sure the car is fitted with a standard Ford Escort SEFI engine loom. Also a while ago I obtained a used ECU of the same type fitted in the Morgan and ran it up on an ECU test rig I constructed. So far I have been able to confirm about 40% of these pin numbers. This is still work in progress. Finally after pulling every fuse on the car one by one I can find no fuse that, if blown, would break the specific “ignition on” feed to injectors, MAF sensor, speed sensor etc connected via pin 5 of the 12 way connector on my diagram. It would seem that this feed is not fused !! If anyone has been down this path before and has found such a fuse I would be delighted to know the details. Apologies for the long post but hope it will be of use to others. Regards Tony ![[Linked Image]](https://www.tm-img.com/images/2025/02/10/The-12-way-faulty-pin.jpg) ![[Linked Image]](https://www.tm-img.com/images/2025/03/03/Morgan-12-and-6-way-connectors.png)
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BigLes, Hamwich |
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Joined: Apr 2008
Posts: 11,856 Likes: 137
Scruffy Oik Member of the Inner Circle
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Scruffy Oik Member of the Inner Circle
Joined: Apr 2008
Posts: 11,856 Likes: 137 |
This is what TalkMorgan's all about! Congratulations on your successful diagnostics Tony. Sorry I can't be of any help regarding the question, but it seems strange that there would be no fuse at all in this feed, doesn't it?
Tim H. 1986 4/4 VVTi Sport, 2002 LR Defender, 2022 Mini Cooper SE
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Joined: Apr 2024
Posts: 51 Likes: 10
Just Getting Started
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OP
Just Getting Started
Joined: Apr 2024
Posts: 51 Likes: 10 |
Hi Tim
Thank you for your kind comments. As for the un-fused feed I couldn't agree with you more, it does seem odd. The fuse panel has 19 fuses with one spare unused slot. I pulled each of these fuses individually made sure the injector power is still present with ignition on and checked that each fuse pulled results in the appropriate service loss i.e. dipped lights, main lights, horn etc. The source of this feed is ultimately from the ignition hold relay permanent live contact. So I wondered maybe this permanent live was fused. One of the fuses in the panel not shown on my diagram is fuse 10 a 20 amp. This is a permanent live to the radiator fan motor. I thought maybe this fuse also breaks the permanent live to the ignition relay contact but it doesn't. The same applies to fuse 9 permanent live to the cigarette lighter but that was not associated either. The only other fuse I know of is an individual 10 amp fuse near the battery connected to the battery positive terminal but that only feeds the radio and for some odd reason the immobiliser LED anode. It could well be me missing something I will keep looking but maybe its a Morgan drop off.
Regards Tony
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Joined: Nov 2012
Posts: 251 Likes: 14
Learner Plates Off!
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Learner Plates Off!
Joined: Nov 2012
Posts: 251 Likes: 14 |
Tony
Fabulous post - many thanks!
Dave Blue 4/4 1969, Green +4 1953, (different) Green +8 1977
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Joined: Feb 2016
Posts: 7,919 Likes: 216
Talk Morgan Guru
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Talk Morgan Guru
Joined: Feb 2016
Posts: 7,919 Likes: 216 |
Excellent fault finding Zach  There are Ford Focus wiring diagrams out there but I admit difficulty in finding the correct engine one for your car. I wouldn't worry too much about what appears to be an unfused feed. Pulling fuses one by one would leave you open to secondary current paths.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
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Joined: Apr 2024
Posts: 51 Likes: 10
Just Getting Started
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OP
Just Getting Started
Joined: Apr 2024
Posts: 51 Likes: 10 |
Dave and Richard thank you both very much for you kind comments.
Richard just to make sure I understand what you mean by secondary current paths. Lets imagine the feed to one head light had failed due to a bad connection in a connector somewhere in its feed path. You replace the bulb still no light. You measure the voltage arriving at the good head light and it is 12 volts. You check the voltage at the bad light and its near zero. You then decide to do a continuity check between the head light switch and the bad head light and low and behold is a few ohms. You scratch your head and think, well the bulb should light even if a little dimmer. What you would have failed to realise is the continuity check you measured is the path from the switch, to the good head light, down its bulb to earth, from earth up through the bad headlights bulb. So the continuity check would have mislead you.
I was once asked by a friend to help him with a problem with the nav light on the tip of his aircraft's starboard wing. The light had failed and he changed the bulb but it was still out. He then carefully probed the bulb holder with a volt meter and it was pretty much 12 volts. I explained to him that the meter was high impedance or more correctly resistance since we are dealing with dc and it would pass a tiny fraction of the current that the bulb would. The result would be almost no volt drop across the high resistance he had somewhere in the light feed whilst measuring with the meter. Hence the meter reading 12 volts. Ohms Law tells us that the voltage on both sides of a 20 meg ohm resistor will be the same if there is no current flowing through it. We fixed the problem but in this case it was a voltage measurement that was misleading him.
I have tried to take into account these sorts of problems when I set about tracing my cables and drawing my diagram and was left with this illusive fuse. I have probably been tripped up by something like this but I am still looking. If I find it I will update and repost my diagram.
Regards Tony
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Joined: Jul 2019
Posts: 4,607 Likes: 192
Part of the Furniture
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Part of the Furniture
Joined: Jul 2019
Posts: 4,607 Likes: 192 |
Not directly related to your quest, but many years back while taking part in discussions with the GoMoG web site`s moderator trying to find an issue with his +8`s EFI system, he ended up opening up the wiring loom to find a fuse wrapped within...???? Given that was a long time ago and my memory was never great and the ageing process is unlikely to have improved matters.... at the time I remembered coming across a similar situation of a fuse within the harness of a BL mini, that it seems at least back then if not still, there are possible issues that do not match imagined best practice even outside the MMC , who I suspect made use of partial wiring systems from the engine donors vehicles as EFI became more common. I have also read all be it some years back where wires changed colours via a loom joint on a vehicle wiring untouched from new, reported by a TM stalwart.. All second hand info, though not in the case of the Mini fuse.
Good luck in finding the source of your ..err...foible.. and thanks for sharing in such detail.
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Joined: Dec 2008
Posts: 21,866 Likes: 167
Roadster Guru Member of the Inner Circle
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Roadster Guru Member of the Inner Circle
Joined: Dec 2008
Posts: 21,866 Likes: 167 |
I remember seeing a BL car with a single fuseholder emerging from the loom, then going back in, but no idea what that was.
DaveW '05 Red Roadster S1 '16 Yellow (Not the only) Narrow AR GDI Plus 4
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Joined: Jul 2007
Posts: 26,747 Likes: 419
Member of the Inner Circle
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Member of the Inner Circle
Joined: Jul 2007
Posts: 26,747 Likes: 419 |
I think my 67 Midget had max 4 fuses
JohnV6 2022 CX Plus Four 2025 MG ZS EV aka Trigger
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Joined: Dec 2009
Posts: 35,773 Likes: 468
Tricky Dicky Member of the Inner Circle
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Tricky Dicky Member of the Inner Circle
Joined: Dec 2009
Posts: 35,773 Likes: 468 |
Pretty sure my 105E had two.
2009 4/4 Henrietta 1999 Indigo Blue +8 2009 4/4 Sport Green prev 1993 Connaught Green +8 prev
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