There are three sets of lights connected to this switch - Tach/speedo, other instruments and the “panel edge”, which I assume is the lighted indicators of each switches function.
I am not clear what is supposed to happen when the switch is in its three positions and the wiring diagram does not show which terminals are live in each position… can someone confirm that with headlights off, none of these lights is on. With the headlights on, the dash lights switch goes as follows:
Switch off - tach off - instruments off - panel edge off
Switch 1 - tach low - instruments low - panel edge full;
Switch 2 - tach full - instrument full - panel edge full.
Since terminal 3 is connected to the output of fuse 5 which has power when the side lights are on, the result is as follows if the side/head lights are ON:
switch off - panel edge ON, tach & instruments OFF
switch middle - panel edge ON, tach & instruments LOW (as controlled by panel light resistance)
switch full - panel edge ON, tach & instruments full ON
So, the same as your description except that panel edge lights are ON in all 3 switch positions.
Same for my S2 (panel off when switch is in position 1).
I don’t think one can conclude what is correct from the wiring diagram as it is possibly the switch internals (“terminals 3&4 connected”) that might make this otherwise.
I’m going by the 1970 Series 2 wiring diagram from Richard Liggitt’s book which includes descriptions of all the switches and relays with details of which terminals are connected in each state. His information is usually spot on. The diagram shows terminals 3&4 as being connected internal to the switch. I don’t know if this applies to my earlier '69 Series 2 - maybe I’ll try it out when the garage is dark enough to see the very dim panel edge lights…
I’m afraid that my test was not a complete success. It did verify that with the panel light switch OFF, the panel edge lights (legend strip) were still illuminated. However, my panel light switch seems to be defective. It has “feel” to it at all. No detents at all. I can’t tell whether it’s 2 or 3 position. The instrument lights come on (very weakly) when the switch is moved away from the OFF position, but there is no sense of it “clicking” at all. Looks like I’ll have to take a look at it when I get a chance…
I have an update on this Panel Light switch, but it is a bit confusing to say the least. It seems that there may be some differences between early and late Series 2 cars in this area. That at least, is consistent with what I have found. My car (which is a 1969) has a Lucas 39225 switch in this position. The date code suggests that it is original. This is a 2-position switch, not a 3-position as I believe you have. Lucas 39225 is the Jaguar C.32855 part. Its 4 terminals operate as follows: OFF - 1&3&4 connected; ON - 1&3&2 connected. Terminal 3 is connected ® to Fuse #5, Terminal 1 is connected (R/U) to the panel edge lights (legend strip), Terminal 2 is connected (R/W) to the Instrument lights (Full), and Terminal 4 is connected (R/N) to the Instrument lights (Dim) via a resistor (this last connection is an assumption, as I haven’t traced the wire to find the resistor). This would suggest that with the panel edge lights (legend strip) should be on full as long as the side lights are on, and that the instrument lights are DIM when the panel switch is OFF, and FULL when the panel switch is ON. Having dismantled it, I find that my switch is not operating at all, so I can’t confirm this until I carry out a repair. What is strange, is that when I look at the Jaguar Parts List, the Panel Light switch is missing (all other rocker switches are there) so I can’t confirm the part number. Furthermore, the connections do not match the Wiring Diagram in the Service Manual - I presume that the issue here is the numbering of the terminals on the switch. This is not the first time I’ve come across this issue:
My Car/Wiring Diagram (attempt at Table)
Connection to Fuse #5 ® 3/2
Connection to Panel Edge Lights (R/U) 1/4
Connection to Instrument Lights FULL (R/W) 2/1
Connection to Instrument Lights DIM (R/N) 4/3
Moving on to the later Series 2 cars, the wiring diagram for the 1970 cars from Richard Liggitt, which also includes descriptions and terminal designations for the switches and relays, shows a 3-position switch with Lucas number 39226 and Jaguar Part Number C.32856. His wiring diagram implies the operating description I described in my earlier post for each of the 3 positions. When I look up this Jaguar Part number on XK’s Unlimited web site I don’t find it. I do, however, find a rocker switch for the Panel Lights for Series 2 and Series 3s with Lucas Number 39599 and Jaguar Number C.34682!
Without knowing what year your car is, it is difficult for me to say much more…
Thanks for your continued research. Mine is the 3 position switch and I was able to figure it out using Liggetts diagram and a continuity tester. I now have it operational and working as Liggett specifies.
I cannot add any more on the two position switch except to say my car is a May 21 1969 build, so presumably not in the “early” 1969 group.
Glad to hear that your switch is now working properly. Having found that mine was non-operational, I took it apart to investigate. The “tophat” that sits on top of the spring with a dimple for the knob on the rocker had disintegrated. I made a replacement out of part of the mechanism of a ballpoint pen. It seems to work fine! Now, for the first time since I bought the car I have instrument lights that come on FULL as opposed to DIM. The DIM level is barely perceptible. The FULL is still pretty dim, but much brighter than before. Can’t wait to try them at night. Thanks to your question, I fixed something on my car that I didn’t even know was broken!
I don’t think I can clarify any further than I did in my posts 4 years ago. There are multiple versions of the Series 2 wiring diagram (neither of which may be relevant to your 1967 Series 1) which differ in the area of the Panel Lamp switch. Some cars appear to have been equipped with a 2 position switch, and some with a 3 position switch. It’s also worth noting that some of the reproduction switches available from “the usual” suppliers differ from the originals, particularly in the way the terminals are numbered. For this reason, I advise anyone to verify which terminals are connected in each switch position before installing these switches as the wiring may need to be adapted to suit. Good luck!
I’m trying to connect my panel lights properly (69 S2) to this switch that I bought from SNG Barratt (wrong switch type was installed in switch panel by PO). The wires are Red (from fuse #5), Red and White (to panel lights), Red and Brown (to panel light resistance then to panel lights) and Red and Blue (to panel edge lights) My wiring diagram shows connections for terminals numbered 1, 2, 3 and 4. This switch has terminals 1, 3, 4, and 5. There is no terminal at all on this switch at number 2.
Any guidance on what goes where is greatly appreciated!
Thanks,
Chet
I spent time today hooking up this Lucas 152SA switch for my panel lights and want to report that it is different than what is outlined in the other post. Specifically: when the switch is in the off position terminals 3 and 4 are connected. When it is in the “dim” position terminals 3,4 and 5 are connected. When it is in “bright” position terminals 1, 3 and 4 are connected. So the correct connection for the panel lights to this switch is Red/White to terminal 1; Red to terminal 3; Red/Blue to terminal 4 and Red/Brown to terminal 5.
