So I drove a night yesterday. Pleasantly surprised by the headlights, on a par with the XK8 (which for a "modern" car are pretty bad).
I had no illumination on the instrument panel. Just took the switch out and magically it starts working. I assume this will happen a lot. Someone has disabled the "Dim" setting by taking both wires to the same terminal so I might restore that just for the sake of originality.

I have noticed the ammeter works the wrong way around, the car has been converted to negative earth so I guess someone forgot to do the ammeter. Thats the next job.

After that work out why the heating fan is not working and the fog masters.

I love working on a car I can understand, this is why I have it. Now the sun is shinning so off for a drive.\

 

if there have been modifications/additions to the car from original you might want to check them for electrical problems too, as whoever did the conversion, if it was indeed intentionally done at all, may not have been aware of the consequences of a polarity conversion. for example, anything involving solid state componentry could be at risk. even an old generator may need to be tweaked. and i've hat motors run in reverse on occasion. i don't have enough information, nor knowledge to give a complete list...

 

I have checked the list of stuff that needs changing to switch it to negative earth. The generator is working so I guess I am OK.

 

The dim setting may have been removed because the lamps have been replaced by leds as most leds don't dim. With the original incandescents, dim is extremely dim to the point of being useless and full brightness is still not exactly right. To be fair to Jaguar, the instrument illumination switch brings out the eccentricity in most manufacturers.

 

Just been able to see the dashboard lighting at full. It’s very dim but makes the instruments visible.

Next tackled the fan. There was power on the switch but the switch wasn’t working.


Isn’t this a thing of beauty?
Dismantled the switch, cleaned the contacts, put in a little contact cleaner and after a little fun (one of the arms came off with the springs!) got it back together and now it works perfectly!

In this day and age when we are fighting for the right to repair I think we forget we used to have it. It was normal, even a switch could be repaired.

Very chuffed. Two repairs and didn’t cost me a penny.

 

This stuff is your friend.

 

When reversing the leads on the ammeter in a MK2 just be a little cautious.
1. disconnect the battery. If you short a live lead sparks will fly!! (and there is a danger of burning up your electrical harness.)
2. Make sure the scuttle vent is CLOSED. If the vent actuating handle is in the OPEN position, you will break the lower plastic annunciation strip when you hinge down the instrument panel.

 

Beginning to wonder if my car was really converted to negative earth? When I select the fog lights all the lights go out. Looks like a short circuit. Should I swap the wires on the fog lights? Anything else I should check. I have found the standard conversion checklist but it does not mention the fog lights.

 

probably should confirm your polarity. i'd simply look at both battery wires, positive and negative, and see which one, positive or negative, goes DIRECTLY to the frame or engine block or transmission housing. it's also possible to use a multimeter, as it will show plus or minus sign next the voltage when measuring it in any completed circuit.

that's what i'd do anyway, everyone attacks these problems differently.

in general, i've found that incandecent bulbs are polarity insensitive.

 

The negative from the battery is connected to the frame and I have checked everything with a multimeter. My concern is that it was not done on purpose rather by accident when someone placed a new battery. The bulbs shouldn’t matter as they don’t care about polarity. I was just concerned that I may now have the plus directly connection to the frame? Maybe I am not thinking about this correctly?

 

Rishi
Someone has converted it to negative earth so stop fretting. The car is running OK.
I have done this conversion many times and it is a no brainer.
The latest was late last year on an S type for a friend who got it as a "barn find".
Your fog light problems have nothing to do with polarity.

 

you say the negative is connected to the frame. if so, the positive is NOT connected to the frame, if it was your car would probably be burning.

 

On an S Type you have a choice. Fog lights or main lights. Never both on together. Peter can tell you some stories about Fograngers & his trouble with them.

 

Then I think I just have a short in the fog rangers. It’s not that the headlights go out which I know is correct but all the lights go out when I switch to F. Will take a look this afternoon. While I have the battery disconnected I will swap the wires around on the ammeter.

 

Yes ~ Peter has had many issues with Fograngers ~ shorts, bad connections etc. They are not sealed like the S Type are.

 

Just check carefully around the main headlight switch for correct connections.
The headlights will not go on when the fog lights are selected.
Are you sure all of the other taillights and park lights go out with the fog lights selected.
I doubt if it is a short circuit as that would probably blow a fuse in the huge 2 fuse panel adjacent to the regulator.

 

Everything goes out and I see a huge deflection on the ammeter. I am also suprised one of the fuses didn’t blow. Anyway just about to take apart and see what’s what

Everything around the switch looks OK.



I have added some shrink wrap over the negative connection to ensure they can't short. Still not working.
Now I will get out the multimeter and see what is going on.

Discovered why my headlights give lots of light. They are halogen. Shouldn't there really be a relay to switch halogen lights?

With the Fog Rangers removed I can switch to F and the side lights are on, headlights are off and there is power on the connector of the fog lights. So the problem is created when I mounts the lights.

 

I've never taken apart one of those switches, but those tabs look bent in the wrong position to me ???

You don't need a relay to run halogen lights, the wiring is plenty heavy enough, just make sure your 12 volt and ground connection are nice clean.
Use conductive grease on your grounds, and dielectric grease to keep out the air on the 12 volt connections.
Do not use dielectric grease directly on any of the connections, its just meant to keep the air out.

 

Switch works fine now so I guess it was OK. It all made sense if you see the inside of the switch.

Anyway caused myself a bigger problem I think. Messing around with the FogRangers trying to get them to work and now the battery is no longer charging. Ignition light is on permanently and the ammeter only shows discharge. If I switch everything off it does not show charge. So now I have a real problem to diagnose!

 

I have the greatest admiration and affection for the Mk2, but I am realistic about some of its weak points. On the basis of the thirty something years my Mk2 was in regular use and having spent twenty years in the Netherlands, I ask the following questions:
How often is it foggy in the Netherlands (I remember a couple of genuine pea-soupers)? When it is, are you likely to take your Mk2 out? And, in the unlikely event that you are driving your Mk2 in fog, do you think lamps that either don't work or point in the wrong direction are any use? Do you want the Fograngers for aesthetics only? If you manage a yes, then by all means keep the Fograngers. Otherwise replace them with some nice grilles. You can use that position on the light switch for alternative front fog lamps that actually work or DRLs or a rear fog lamp hidden in the reversing light or ... .