Name that part!

Had this “leftover” from my resto work on a SII 69 OTS. Any help would be welcome. markings show a type SV
150 V DC 1pF.

Looks like a capacitor. I’m guessing radio noise suppression. It would be nice if there were a ruler or coin in the picture for scale.

Is the connector a 1/4" Lucar? It might be the suppression cap across the IVR. Probably aftermarket replacement, as far as I know the originals were metal can type, but that one looks like plastic.

At least for my S3 from '72, that capacitor is original. There is a similar one (lower left corner of picture) for the IVR as Andrew said, but that one as a different connector for ground. Yours has a screw-under connector on one end which looks like the one in the upper right corner of my picture.

  • Manfred

Are Series IIs suppose to have one of those? I’ve never seen one before.


This looks like what you have:

I found it when rebuilding the front of my '69 OTS. I recall reading that noise suppression capacitors were placed in various locations - not sure if this would be from the factory, or the dealership. As you can see, this one is on the picture frame or engine frame rail close to the upper A-arm fulcrum. I can’t tell what the wire is connected to from the picture, and my notes are 700 miles away. maybe this will trigger someone else to take a look in that area on their car, and help you out.


I had one of those on the 69E connected to the antenna in the trunk.

Per W. Schuster, me too I have one of those on the 69E connected to the antenna in the trunk.

Manni, Your very helpful photos showed up another question that I have re wiring connections. Lower left in two photos show the hazard switch with a green wire which has a small yellow “sleeve”. I have not been able to determine where the other end of that wire connects when it comes out from under the left side of the steering column.

Is that connection visible on your car? Any help would be appreciated.


Radio noise surpressor…

According to the S3 wiring diagram, it goes to the flasher unit.

It is a noise suppressor.Mine was attached to the engine block and the other to the coil.

And while we are on this subject … the metal connection bracket obviously goes to ground but does the lead go to a positive or negative. I did not mark it when I removed it.



Hi Bob,

The lead will always go to positive. I have a bulletin from Jaguar to dealerships circa 1970 recommending installation of six 1 mfd caps on the alternator, coil, fuel pump etc for radio noise. I will locate and post. I’ve been looking for a source for these retro style 1mfds, but no joy yet, although did find some other value caps.

Mil-spec, on eBait.

Thanks for the connection tip.

One little question. Manyreplacement caps do not specific their size. How does one determine the micro farads?



Some digital multimeters have a capacitance scale - they measure the rate at which voltage builds up on the capacitor using a current generator in the meter. This is probably the easiest way. The value used in noise suppression is very small. Paul

Yes its used as an X capacitor, for noise they are usually 1-10 mfd’s. since they are basically used to filter out high freq in the line voltage they rarely go bad( besides a broken wire possibly) . your good using anything from 1mfd to 10 usually and they can be rated at any voltage higher than 12v.

Once again, thanks!


Hi Bob,

Here is an excerpt from the Jaguar Bulletin to Dealers (courtesy of the Coventry Foundation). All of the capacitors I’ve seen on actual Series IIs and in reference books have been metal cans like the one in David Langley’s post earlier in this string. Lots of directions online towards using your vom to determine capacitance.

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Excellent information!

The circuit diagram does not show these capacitors.

Many thanks,