In the process of performing an oil change on my 70’ FHC (S2) I noticed a loose wire (white with black stripe) in the vicinity of the distributor. Looking around, noticed an empty spade on what I believe is the relay for the oil pressure sending unit which is mounted over the oil filter canister. This relay has an existing wire connected (white with brown stripe) on the adjacent spade. Would I be correct in assuming that this loose wire gets connected to the adjacent spade? Checked the wiring diagram but no help.
No. You would not be correct to connect that White/Black wire to the oil pressure sender. The White/Brown wire is the only one that should go to the sender. The second terminal is unused. The White/Black wire is probably used to connect the distributor to the negative terminal on the ignition coil. If you have replaced the standard points/condensor on your distributor with a Pertronix or similar pickup, or replaced the entire distributor with an electronic distributor such as a 123, then that White/Black wire is no longer used. You should just put some tape over the end, and tie it up out of the way.
No. The OP’s car is a Series 2. No Oil Pressure switch to drive the ignition light - it uses the 3AW. Wrong color wire too. The Oil Pressure Switch (not to be confused with the Oil Pressure Sender) which was only fitted to some 4.2L Series 1’s has a Brown/Black (NB) wire. The photo from the original poster around the distributor area clearly has some non-original wiring (red) in the frame, so I’m betting on an electronic “upgrade” to the ignition system, which likely removed the need for the original White/Black wire from the distributor to the coil. Just need the original poster to confirm that is the case.
Sure, I didn’t believe it drove it, but it is nevertheless there, seemingly identical, and perfectly placed for the switch connection. But yep, wrong color.
I have a '72 S1 XJ and they’re no doubt the same.
I looked at wiring diagram for my car, because I’m a nerd, and NB goes to the oil pressure switch to light. Another NB from the 3AW to light, then W from the light to Fuse 6.
WB to the distributor BTW, as the photo above.
That wire and sheathing look spot on for it too(not to mention sender/switch/temp sensor wires I might add), color codes notwithstanding.
Appears in background a bundle of red/black wires no doubt for elec. ignition upgrade, so you’re probably spot on.
I’ve attached a wiring diagram for the S1 XJ6 which should also apply to the car numbers shown below on the chart. If it looks different than a S2 E, please speak up…I’d be curious to know. Jaguar always made point to cross pollinate dontcha know.
Hope it helps.
Ok, I’ll go back and play with the XJ kids and not cause possible confusion.
Thanks David, yes the car was replaced to a Pertronix ignition by the previous owner. Don’t have issues with the oil pressure gauge or light, so that seems the likely explanation.
I second David’s advice to put some tape of the end of the spade terminal. Remember that the white and black wire is still hot while the ignition is on and if it shorts against the frame the engine will cut out momentarily and maybe just stop. This happened to me in my MGB in the mountains around Lake Tahoe. In fact it shorted out so many times that the Pertronix finally failed.
Andy S2 with points.
