Where is the Starter Solenoid on a 73 XJ6?

(Lou) #1

Sorry to start a new

(Lou) #2

Sorry, the item go posted before I was finished.

Can someone tell me where the starter Solinoid is on a 73 XJ6. I know I could use the sound to find it, but I am alone this weekend and can do both at the same time.


(Carl Hutchins, Jr. ) #3


Down and under. Atop the starter motor.


(Carl Hutchins, Jr. ) #4

Solenoid. A device that in this application converts electrical energy into mechanical movement and simultaneously switches
electrical energy,


(Lou) #5

Thank you. Ugh! What a difficult place to work.


(Robert Wilkinson) #6

There is another source of clicking besides the solenoid. That’s the starter relay. It’s located roughly above the starter solenoid–on the bulkhead (firewall). A thick wire attached to it is the one that goes to the solenoid. Connecting battery voltage to that terminal is the same as connecting voltage to the solenoid. Relay click is nowhere’s near as loud as solenoid click.

Great that you got a rust-free car, Lou! I am now jealous of both you and Rust Free Mike!

(Lou) #7

Thanks Bob. It is satisfying that this car won’t be eaten by the tin worm as the 71 is.
With the 71 having such severe rust problems, I always questioned what I was doing; am I wasting my time, is it worth it, etc.

Your email is really ironic. I spent the afternoon attempting to determine what the cause of the non-start is…an failed miserably. :(. Not really, it’s a beautiful day here in Pennsylvania and getting back into Jaguaring felt good.

OK, so here’s where I am. Frank sent me this great email that gives me precise instructions on how to test for three potential problems; the ignition switch, the starter solenoid and the starter itself. But I was unable to do the test because I could not find the point where the four wires that Frank spoke of came together: black/green, white/yellow, white/red and brown. I assumed they were on the firewall. But only the brow is.

And that’s why your email is ironic. I though that perhaps the relay you refer to in your email, which I now know is the starter relay, was the place. It does have the brown wire coming out and going to the starter, but that’s it.

Maybe the wires are in the starter motor itself. But if that is the case, I am never going to get to them without removing the intake manifold. The only wire I see going into the starter motor is the thick black wire you refer to in your email. I did remove the end from the firewall post and found a fair amount of corrosion, which I cleaned and reconnected. But that was not the source of the problem, as the starter did not spin. :frowning:

However, the thought occurred to me that on my 71, I have tested the starter by connecting a remote starter But, the 71 is a different starter motor on which you could quickly disconnect from the large black wire by just pulling it off and clip the remote starter onto the stud.

So tomorrow, I’ll remove the thick black wire from the firewall post and connect it to the remote starter. That should at least tell me if the starter solenoid and motor are working.

Thanks for your thoughts.


(Robert Wilkinson) #8

Right, Lou. I use a remote starter all of the time that way when setting valve clearance or getting the timing marks at TDC.

Not sure you are referring to the right wire, though. A VERY thick wire goes from a post on the firewall to the starter. This wire is always hot…the post is connected to the battery +, to another post on the left side of the firewall, and to the alternator. That’s NOT the wire.

Rather, a thinner wire (maybe 3/16 inch OD) comes from a quick disconnect terminal on the relay and goes to the starter solenoid. That’s the wire to use with a remote starter switch (other side of switch clipped to the battery + terminal). You can unplug the wire from the relay terminal or just connect to the terminal with the wire attached. Either way, it should activate the solenoid and, via the solenoid contacts, activate the starter as well. Let us know!

(Frank Andersen) #9

As Robert says ‘thick black wire’ is the wrong colour…

‘Brown’ is the colour for permanent power, plain black is always a direct ground connection - and there are no ‘thick black wires’ originally used anywhere. I suggest you check wire colours carefully; in some cases the wire colours fade or deteriorate. There is also the possibility that a PO may have replaced wires with no regard to original colours…

…and POs sometime does the oddest things! Either you are not looking at the starter relay - or it’s wiring is completely haywire. The starter relay has 5 terminals, though only 4 is used for the actual cranking. One wire (nominally white/red) connects the solenoid to the relay - which is the one Robert refers to when using the remote starter. It’s imperative that the wire is properly identified as going to the starter solenoid - which is indeed, as Carl says bolted to the starter housing. You simply have to access the starter motor to identify that wire…

…no ‘ifs’ or ‘buts’ - unless you can verify that you have positively found the starter relay proper, identified by the relevant wire colours - and all relevant wires are connected to the relay, nowhere else. Again; you are either looking at the wrong ‘relay’ - or its connections are totally messed up. In which case that has to be sorted before any progress can be made…so…?

xj6 85 Sov Europe (UK/NZ)

(Lou) #10


I just realized your post has the answer in it on how to use the remote starter. I must have gotten up on the wrong side of the bed this morning

I’ll try your suggestion tomorrow.



(Robert Wilkinson) #11

Good luck, Lou. Be sure to have the car in Park. You are bypassing the neutral/park safety switch, and of course the ignition/starter switch. With the ignition switch off, the engine should turn over but not start (assuming the starter and solenoid both work). With ignition on, the engine should start. The car can move in either case unless it’s in Park (or neutral, but that’s not as good IMO).

(Carl Hutchins, Jr. ) #12


No! I hope you did not disconnect the big black wire at the firewall post to remote crank.

Leave that post alone. Except to clean and tighten the connections.

Down and under. I see no need to remove the intake manifold???

The face of the solenoid has three connections.

  1. Big “wire” from the fire wall post.
  2. small connector for the r/w from the starter relay.
  3. A strap from the solenoid to the starter motor.

Don’t mess with these other than clean and tighten.

As Bob says, you can jump 12 v to the connector for the small r/w wire to crank, but not start. CAVEAT, as he warns. Double
caution intended.

If it does not crank other stuff to fix. Low battery most likely.
Dud starter or solenoid also possible.


(Frank Andersen) #13

The crux is to ensure he is on the starter relay, Carl - and not looking anywhere else…

All relevant tests can be done there - access the starter and solenoid is relevant only if the solenoid operates and the engine fails to crank. A sometimes fault is burnt contacts in the solenoid, preventing adequate current flow to the starter. Or a fault in the starter itself…

xj6 85 Sov Europe (UK/NZ)

(Lou) #14


Thanks for your guidance.

I did disconnect the large, branded copper wire on the firewall because it looked like it had never been disturbed since installation. There was a large, heavy duty angle rubber cover over it. With the application of some silicone, I was able to slide the rubber cover up the wire to access the 9/16" nut holding it in place. And in fact, both the stud and the nut holding it in place were moderately corroded. I cleaned it with a wire brush and steel wool and reassembled, and slid the rubber cover back in place. I was looking for a bad connection to the starter, but this was obviously not it.

Regarding removal of the intake manifold, I only mentioned it to highlight the difficulty of access the starter. It would be the last thing I would do. I assume the starter and solenoid are usually accessed from underneath, which I hope is not necessary.

I think that I will wait for Saturday so I can hopefully perform all the tests Frank suggested in one day.

I am mildly concerned because the starter relay does not have the while/red wire that Frank spoke of, although it has a white/green wire that was not mentioned. I must get out the wiring diagram and see if I can find that.

As Frank said, the 73 was a transition year. I should check the Series 2 wiring diagram. As I mentioned in a post some time ago, this car is close to the end of the run, I think it was 4000 cars from the last.


(Frank Andersen) #15

The wiring colours for the cranking circuits, solenoid and relay, were unaltered throughout, Lou - there were no white/green on the starter relay…

What other colours do you have on that relay?

I have actually not found any relay with a white/green wire, which is neither here nor there - but the starter relay always have a white/red. So, you are either on the wrong relay - or someone have done a ‘funny’. The only reason then for accessing the starter solenoid is to verify the wire colours there - which should be the fat black and the white/red. However; ff the wire on the solenoid is indeed white/green it would serve - it’s not the colour but the wire that carries power; colour is for identification. Certainly if power is applied to the (disconnected) white/green and the starter solenoid operates, it is proof enough, and the white/green can be regarded as white/red. If not - it proves nothing…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

(Paul M. Novak) #16


I don’t know anything about the Series I XJ6 but a White-Green wire on a Series III XJ6 or XJ12 is for the Fuel Pump.  Is it possible that you have the Fuel Pump Relay confused with the Starter Relay?


Paul M. Novak

1990 Series III V12 Vanden Plas

1990 XJ-S Classic Collection convertible

1987 XJ6 Vanden Plas

1984 XJ6 Vanden Plas

1969 E-Type FHC

1957 MK VIII Saloon

Ramona, CA USA

(tony) #17

The SM changed about '73 from a SM45 to a M100, and the Solenoid wiring is somewhat different

The older larger M45 has 2 big push on lugs, and the M100 has a brass screw with a wire leading off

I have permanently fitted an engine cranking switch, and its ideal for testing Starters.

a 30A MOM switch is fitted directly from + battery terminal to the solenoid wire

a 73 should have the older style SM, which can be easily distinguished, cause it has a sheet metal cover clamped around the brushes

I had some starter issues and used this to help nail them down, and its perfect for doing timing etc

As others noted, precautions MUST be taken to avoid any possibility of starting vehicle, including chocks

(Lou) #18


I don’t know what the purpose of the purpose of the white green wire is, I just know it’s connected to the starter relay.

Below are three photos of the starter relay and the area around it… The center photo is of the relay, after removal from the firewall and looking at it from the back. From left to right is the black wire, the white/green , brown, and the white wire hidden behind the black/green wire. In the bottom photo you can see the white wire better. All these wires plug into spade connections in the relay.

The top photo is of the area just to the left of the starter relay. The circular connector in the top right of the photo is where the left side of the relay is bolted to the firewall, through the connector. You can clearly see that there is what sees to be a white/red wire. However, it’s not connected to the relay. It comes down from a bundle of wire running at the top of the firewall behind the battery. Just after it emerges from the black tape holding the bundle together, it makes a 180 degree turn and goes back into the bundle of wires which you see in pictures 2 and 3, from the starter relay.

So there is a white/red wire but not connected to the relay. I looked but did not see where the white/red wire comes from or goes to. I don’t know what to make of this.


(Frank Andersen) #19

As per earlier post from Paul, Lou - the white/green may be to the fuel pump…

However, none of my diagrams show the fuel pump for the carbed engines - and the digrams of the transition year is confusing. I suspect Jaguar did not scrupulously update the diagrams (or indeed specifications descriptions during this time - there were something haphazard during rapid changes.

A fuel safety relay was added for sometimes during the transition, but do not have the colours you describe. Nor do I have the pleasure of your pictures for clarification - I am sort of stumped as to the identity of ‘your’ relay. But it does bear the characteristics of a fuel ‘relay’ - or related to fuel. With the fuel pump running; try disconnecting the white/green to see what happens…?

However, all diagrams are united in one thing; the starter relay has one stand-out feature; there is a white/red (to the starter solenoid) - and a white/yellow (from ign key, powered in ‘crank’). Even Jaguar cannot be so perverse as to produce any car within the ‘series’ that deviates from this standard. In short, whatever ‘your’ relay is; it is not the starter relay…

Unless you can find the other end of that white/red at another relay; the most conclusive check is to go to the starter solenoid - to verify absolutely the wire colours there. Which will tell what colour to look for - if it is not white/red. But someone out there should know precisely where the starter relay is located on the SI and/or SII…???

xj6 85 Sov Europe (UK/NZ)

(Lou) #20


I want to do the remove starter test on Saturday. So I pull the black wire off the starter relay and connect it to one of the two wires from the remove starter. And the other wire from the remove starter goes to the positive battery terminal? Correct?