The 'E' Type Forum

I have recently had a problem with the ignition switch of my series 1.5 2+2. Some things on my car are S1 style and some are S2. I have toggle switches, a separate starter button, and wires that tally with S1 wiring diagram to be found on this site.


The switch would only work when the key was pressed in a bit and so was faulty. I ordered part no. C28522 (which says it is for the S2) from SNG Barrats because the photo for the S1 part C22258 appeared from the photo to only have two terminals and my old ignition unit has five terminal connected. The back of this new ignition switch looks like this;



which is quite unlike my original which looks like this;



I used my best judgment to connect up the ignition unit, as there were no instructions. The car started fine and started again after a stop on a drive. However, the next time I came to start it, it was dead. The battery was totally flat despite there being a conditioner on it. I charged up the battery, which was just over 3 years old. The very next day it was totally drained again. I took the battery back to Halfords and they tested it. They said it was at the end of it?s life, but was not faulty. The manager gave my a good discount on a new battery. I put it on the car and the next day it was flat. I requested instructions from SNG (which I feel should have been supplied without request) and after some time I got this;



Look again at the photo of the new switch and notice how totally different the terminal numbering is. Plus they included this;



Which is for the S2 and wire colours don?t correspond to my car.

Using a multimeter I tested my old ignition (which has no starter function) and found that the double center terminals, which would appear to be No.3, are never live to any other terminals no matter where the key is set. The Brown/Red wire and the 2 linked Brown/Purple wires seem only to permanently connect to each other and nothing else which seems very strange. Why not just joint them together? When the key is turned either way terminal(s) no. 4 are live (for a radio I assume, but nothing is on them) and when the key is turned clockwise terminals 2 and 4 are live with the No.1 feed (Brown/White).

To cap it all off, I tested the old unit again and found no fault at all. I did not have to push the key in to make connection, so I have re-fitted it as it was, but I would still like to solve the mystery of what the heck is going on. I think the wiring diagram is very deficient for not labeling the terminal numbers and showing the connections made in the various key positions. Perhaps something could be done to improve it (as it appears on this site anyway)

Sorry to be so lengthy, but I have to give all the details or there will only be more confusion.

Kind regards to everyone for a Happy Christmas

Andrew

Andrew,

Although we are in touch by private message, just to share my findings to the wider E type community.

I believe there were four Lucas Ignition starter switches :-

1961 - 64 Lucas 30608
1965 - 67 Lucas 34679 (as referenced in the Jaguar 4.2 Parts Book as C22258)
1968 - late 69/early 70 Lucas 34680

Then after late 1969/early70 they went to Lucas 39679.

Note the subtle part number change in the the 67/68 period around the Series 1 1/2 period.

The 34680 was used in several UK cars such as Triumph and Aston Martin and now appears to be the switch offered as a replacement for C22258. This Lucas part number 34680 also cross references to Lucas part number 31873 and I have an unused original Lucas 31873 still in it's Lucas box and packaging. This has the same terminals as your Lucas 35598 diagram which is now generally offered as the replacement for the 34680.

I am still uncertain as to the connections on the 31873, but over the Christmas period I 'll check it out, as there may be a subtle diffences between the 39679 and the 34680 to justify listing them as different part numbers. I'll also drop my dash to check what switch I have on my 1967 4.2. All interesting stuff !!!

Regardless of this - I send Christmas wishes to the E type Forum members with the wealth of information exchanged over the year and here's to 2014 and all that brings us !!!

regards,

Dave