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Discussion Starter #1
Hi I recently bought a 1976 Silver shadow, which runs well but has a ignition light that likes to be on all the time unless the engine is running, it has a CAV Alternator and has a new regulator box but the same fault is present, also with the Key out of the ignition the radio, seats, wipers and drivers window all work, just wondering if anyone else has come across this problem, started to check through the wiring but its a bit like spaghetti ! lol
 

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Martyn,


Well the spaghetti approach did not get any reaction.


I still think you should do the fuse pull test and remove each one to see if the supply to that gen light is coming from any fuseboard supply circuit or direct from battery circuit unfused.


Also did you fit a CAV regulator would like to see a picture of what you have there in the engine bay.


Also probably need to check each wire has been placed correctly even if you just did like for like change it needs to be checked someone else did not misplace a wire.


Keep the post updated as you do things.


All the best


Steve
 

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Discussion Starter #3
Hi Steve, I have now removed all the fuses in the "fuse box", the light is still on, a friend tonight suggested that I take off the Alternator feed wire to see if the light then goes off, he works on heavy goods vehicles and said that is what he would try next.
the nights are drawing in now so will have to leave it to the weekend to try something else
regards
Martyn
 

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Hi Martyn,


I agree, my next steps would be to remove the Brown/yellow wire at the regulator see what happens, then remove the brown/blue wire again at the regulator box.


The key now is to find what puts that light out then focus in on where that line circuit and how it could be picking up a permanent supply.


All the best


Steve
 

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Discussion Starter #5
Hi Steve,
if I remove the WL wire , the light goes out, but stays out when the ignition is on, sorry I don't do colours, do you know which terminal these wires go too? will do more investigation Saturday, and keep you posted
Martyn
 

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Martyn,


I don't see a WL wire. Is this a marking stamped on the regulator somewhere. The print on the schematics can sometimes be a bit blurred on the wire ID.



Take a picture of the area it may show up the colours or mark up the wire you are removing as that will be a good starting point now.


Not an easy area or subject I accept for someone who is colour blind. At least the schematics are in black and white.


I will be around over the weekend. Did you get my email address and home number.


Steve
 

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Martyn,


OK found the WL (I think) it is very blurred on the schematics I have but it is the markings on the regulator box casting.


The brown/yellow wire here is direct to one side of the gen warning light so that is good the light now goes out. The schematics show two Brown/yellow wires on the drawing connected here. Not sure if these are crimped together or just linked on separate terminals. Can you confirm as it may need each one removed separately to trace a fault. You might need to be diving in behind the regulator to the thermal delay and choke solenoid circuit and this is a pain to get at.


Next connection to it on the regulator is marked A and is Brown/blue. Leaving the Brown/yellow WL wire connected now remove the Brown/blue wire and see what happens to the gen light with ignition key in OFF position.




Its beginning to look maybe like a duff diode in the alternator. Possibly a good clean down at alternator connections would be a good start at the weekend.


Regards


Steve
 

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Martyn,


I am going to dive in here feet first and give you something to look at.


The two brown/yellow wires at the regulator WL are linked either crimped together or linked at the Lucar connectors on the regulator.


One wire is direct to the gen warning light the other goes to the cintilla thermal delay switch which energises the choke solenoid to keep the carb induction flap closed on initial cranking. The choke solenoid when energised on initial crank will not actually pick up and hold the flap unless you go through the procedure of pressing the accelerator pedal down before cranking. Choke will stll work as that comes off the manual choke coil which is heat related from the exhaust manifold.


That aside.... it is quite possible you have a fault inside the cintilla thermal switch as these are a problem......I have lots of faulty ones but have not found a suitable repair method yet. See the picture below.....Jean7 if you are reading this.... one day I will:devil. I have been able to repair some when it has just been oxydised contacts and the elements and insulation good.


My thoughts here are maybe the element wire has broken (which they do), and making contact with the bi-metal blade or the insulation on the blades has broken down (which it does). As there is an earth circuit on the thermal blades if the element has broken away or insulation rotted through you may be getting a circuit through the gen light that is keeping it alight.


Just something for bedtime reading and following the schematic before you start at the weekend to get your head around.


What I would do is (ignition OFF) and the brown/yellow wires removed is test the wire and see if it does go to earth. If the brown/yellow wires are separate then you can test each one individually disconnected from the regulator. If the light goes out with the choke thermal switch disconnected then for sure this is now where to start looking. Unfortunately the thermal switch is tucked under the metal housing with a lot of other relays. I can see you have speed control which makes it even harder to get to.



Do the quick wiring check and see what the results are and let me know.


Regards


Steve
 

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Discussion Starter #9
Hi Steve,
head is spinning already,lol, have just pulled off wire A (Brown Blue? two wires in one connector.) the light is out all the time, so does not come on with ignition in either ACC or On. wipers and seats still work with ignition off. checked for current with all wires fitted to regulator, WL (brown Yellow?Two wires) 2.36 volts, A (brown Blue, two wires) 2.36 volts, Black wire - sign .01 volts, F Brown Green single wire 0.82 volts and Hi (Brown single wire) 12.37 volts this is with the ignition in the off position. Med and low terminals there are no connections. not sure where to find the item in your thumbnail, are they plastic or ceramic? I have three ceramic discs on the inner wing near the air conditioning sight glass next to the radiator.
regards
Martyn
 

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Martyn,


Let me digest the information. All those volt readings need analysing but I don't really take much notice of volt readings on a multimeter they can be spurious and give false impressions.The items on the front wing are just the fan speed resistors so nothing to do with the problem.


The thermal choke cut out as I have pictured above is hidden as is about 10 Lucas relays under the metal housing that the regulator sits on. Even worse there is a printed circuit board which gets contaminated.


Time for a rethink though if the seats and everything (accessories wise) works with these wires disconnected and key off.


I will put up some pictures tomorrow what is underneath the blower motor and behind the regulator just for your reference.


Thinking now this is either some serious screw up behind the fuse board as you said it looked like tampering or just a simple problem with the ignition key switchbox problems.


I see you have fog lights now from the garage pics and a vinyl/everflex roof. Does your switchbox have a 'FOG' position as these were an accessory. If aftermarket usually the switchbox has not been changed so does not work the fog lights or have the decal......


And I thought I was going to get a good nights sleep tonight:crying


Will be around at home at the weekend


Steve
 

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Discussion Starter #11
don't loose sleep over this old lady! lol
the front fog lights work from the main lighting switch, the last position says Fog, which operate the front fog and turn out the headlights. will have a play around tomorrow, its not going to beat me!
regards
Martyn
 

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Discussion Starter #12
Hi Steve, Alternator now back in place, the speedo will only go up to 99999. I pulled out the switch panel, and pulled off all the wires that had spade connectors, Gen light remained on,( found another Live wire coming out of the switch, Black Blue going no where). looks as if someone has been in there before as a screw head down in the bowels of the switch has some damage on it, I think you are right, the problem is in the switch, I will take it apart but that's a job for another day I think!just one other thing I just remembered, the central locking works on both front doors using the passenger inside switch, but not when trying to use the drivers inside switch or key.
Martyn
 

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Hi Martyn,


At least the alternator connections we now know are good and clean.


Yes the 99999 speedos don't tell the truth and it is quite possible your car has done 150,000 miles despite showing 50,000 on clock.


Only the full service history records can prove this as MOT history only goes back a few years on the records.


You could apply to Swansea for the owner history as you get a copy of all the old log books as they changed hands and it was an optional extra to add the recorded miles when changing hands.


The door switches are not a problem. Very simple just Burgess microswitches screwed to a backplate top and bottom. Cheap and cheerful to fix but maybe not likely both would go faulty so perhaps this is something to do with the wires that are loose going into the drivers door.


Your rear ones I suspect will just be seized rods in the solenoid. Again not too difficult to free up but the coils can be burned out easily if people keep pushing the switch or leaving pressed too long.


I have emailed you some areas where you can find info on rebuilding the switchbox contacts.


Also if you search 'youtube rollsroycenut switchbox' you should get to the link where he strips a cloud one out but they are fairly similar.


All the best and have a good day.


Steve
 

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Martyn,


That Black/blue wire is certainly a key part of the ignition circuit and shows it going to the regulator and also on one schematic it shows it at the 'park' position.


Can you just do one test. With engine NOT running turn the key to the run position then move the gear selector to drive. Then see if you can turn the key back to the OFF position and remove the key with the gear selector still in 'D' position.


I think it really important now you do get this wiring sorted quickly as it appears to be part of the gear selector interlock circuit and the regulator circuit.


Looks like you are in the right area now where the problems are arising from but also need to know WHY someone would have done this so perhaps some other issues will come to pop up unless the back of the switch is badly corroded on the contacts and maybe causing fuse circuits to blow.


Keep the thread updated. If you don't find enough pictures and information from the web then I will get my spare switchbox out and take some pictures of the back of that one but mine does not have fogs.


All the best


Steve





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Discussion Starter #16
Hi Steve,
carried out the test you asked,( heard the relays in each gear operate) and the key came out of the ignition as normal, but, bearing in mind the Gen light situation , does the car think the ignition is still on? so not stopping the key from being removed?
regards
Martyn
 

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Martyn,


I might not have explained this right.


It is not the fact the key coming out of the ignition barrel but whether it lets you turn the key to the OFF position.


I will do a reccy on my car tomorrow but I know I had to leave my key in the car ignition when I stored it up at times as I did not want the park acctuator to engage just in case there was a problem when I needed to move the car so I always keft the handbrake off and in neutral but had to leave the key in the barrel.


Will check tomorrow and update what is the NORM. Hopefully someone else may respond as to what should happen as to be sure I could never turn the key to OFF unless the lever was in P position.



All the best



Steve
 

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Martyn,


I might not have explained this right.


It is not the fact the key coming out of the ignition barrel but whether it lets you turn the key to the OFF position.


I will do a reccy on my car tomorrow but I know I had to leave my key in the car ignition when I stored it up at times as I did not want the park acctuator to engage just in case there was a problem when I needed to move the car so I always keft the handbrake off and in neutral but had to leave the key in the barrel.


Will check tomorrow and update what is the NORM. Hopefully someone else may respond as to what should happen as to be sure I could never turn the key to OFF unless the lever was in P position.



All the best



Steve

Steve, I am not sure what you are saying about the key not being able to go to the OFF position, I assume you mean if the selector is in anything other than P or N.
All I can say is that the key on my Shadow will go to any position whatever position the gear selector is in.
When the key is pulled from the ignition that operates a micro-switch in the switchbox which in turn puts the gearbox in Park.

Not 100% sure but I think if you turn the battery isolator off while the gear selector in N and key in the ignition, the box will not go into the Park position.

Jake.
 

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Discussion Starter #19
Hi Steve, rechecked the wires, the black blue wire was actually Black Purple which goes deep into the switch along with a Purple, red and brown /black, I think the other wires are terminal 3 Brown/ slate (2 Wires) 6 Brown Red (2 wires) 2 Lrg Brown/white (1 wire) 12 Black (2 wires) 11 Brown Green 10 Brown / Purple, 1 White/ Black and Grey 5 Brown (2 wires)
regards Martyn
 

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Hi Jake,


Yes I think I mean something like what you are saying. I told you before I am getting OLD.


When I was a young 'globetrotter' and a lot more grey cells in the brain which have slowly migrated out to the hair, I had too many cars and some used to go into a warehouse for professional storage. Insurance at that company required the car to be left out of gear, handbrake off and battery disconnected so in case of flood/fire the cars could always be pushed.


I just remember something 'quirky' about the RR switchbox that did not let me do that as some of my other cars did.


I will go later to the car when it gets lighter and test to see what I was meaning but it is something on the lines you describe.


Martyn,


OK no problem with the colours they are difficult to judge sometimes even if you are not colour blind as the cotton ones fade and the plastic ones the colours of the wire and tracer can have blended/migrated into each other.


I will have a look at the schematics from what you have now found and see what may be happening.


If you have looked at the exploded view I sent you of the switchbox you will see just how complex it is. When I had a problem many years back I got a spare just for reference to have on hand when I stripped mine down as the assembly has to be precise with fibre insulators in between rotory cams etc. I actually found my old hand written drawings in my workshop manual of the sequence when I took it apart. Back then there were no digital cameras or access to the internet to get help or information........so much easier today



Will come back later with any information or ideas but I still think you are in the right area now where the problem is initiating from.


All the best


Steve
 
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