Some really good input Bernie, ideas / suggestions coming thick n fast.

Please keep this thread updated as often as possible with any new developments and hopefully between us, we can get to the bottom of this and get this baby up n running, looking good for the wife.

Best

Jim

 

Yes!

All very good information.

Honestly, have not done a lot yet.
I have been swamped with regular work but I have been doing a LOT of reading at night on the forum trying to keep my head wrapped around common issues.

I started to go through all the fuses yesterday but got pulled away on other things. What I did accomplish today was to find and identify the problem with the trunk lock which turns out to be that infamous little microswitch. I wiggled the plunger around a little and the trunk lights came on. It is very intermittent so I taped down the plunger and voila, the trunk button works.

Next I am going to tear into the drivers door which has a door lock that mechanically refuses to go down. Can't even push it down so the motor has no chance. I think these things just all need to be cleaned and properly lubed. I am certain there is a back-pressure over ride on the door locks or else they would simply destroy themselves if they encountered resistance.

The sunroof does indeed have to be repaired. It was sticking up a little but I have since worked it down into the closed position. Now we live in Las vegas so there is not a lot of rain here but I am definitely pulling the computer to check the connections. Who knows if it has gotten wet before?

Hopefully tomorrow I will have gone through a number of relays as well. Have to run now on other business as usual but I will be back soon!

Bernie

 

Hey Lads,

I took the computer out yesterday just to be on the safe side with possible water getting into that area.

It looks clean to me.
Looks like it was swapped out in 2002 though for some reason?

Moving on for now

 

Hey again Bernie,

The car should crank even if the fuel pump is not working. In my experience the ECU does not have a pressurized fuel system signal. But like Avioni says, you should hear the fuel pump prime before cranking. See Kirk's current thread Intermittent stalling.

ECU pins look great. On 8/12/2002 Your car got the new EGR valve and ECU programming update. You should have a R493 label by the left hood hinge too. Keep going, you'll get there!

 

My very 1st post in the X300 forum after a long while lol
It just very lovely to see such cool topics , restoration projects as always and I appreciate you have done everything to bring your Jag back to it's heyday
As far as I remember , Doug is one of the most helpful guys in Jaguars as well as motorcarman
BTW, if you don't mind great to see Stu in here because I know him from UK Forum and one of the nicest persons you can meet in the net

 

Hello Cadillac, glad to see you in X300 land. Ten thousand posts.....

Yes, Doug is an icon of prompt, sensible advice and humor. We appreciate him and the techs like Bob that tolerate us fumbling about our Jaguars! Stu certainly has a way with words and is always entertaining...

Bernie is only days away from cruising in the XJ6...

 

Hi , there are other top posters and I am not among them lol
This place would not be as entertaining as it is been w/o those cool guys
Happy driving

 

Hey Gents,

Back to work on the Jag. Had business trips and had to shelve it for a little while.

Started testing relays yesterday and the four blue ones mentioned all test out perfectly. Moving on to the black ones in the engine bay but need help understanding how to release them from their mounts? Certainly don't want to break anything and its not apparent how they release to test them.

I am still drawn back to the fact my ignition key rotates almost a quarter turn in the barrel before I meet the first stage of the ignition? If all my relays check out, I think I am going after that column next.

Working on my cycling door lock issue as well.
The passenger rear lock does not cycle at all when locking or unlocking the drivers door. Going to pop the card on that one today to see what is preventing it from operating. Something tells me that's why the locks are cycling.

I also rebuilt a new door card for the drivers door last night. The PO had bought a used one which was marginally better than the original but after combining parts from both, I was able to build a pretty mint one.

Input on the releasing the relays is very helpful at the moment.

UPDATE!

Took the passenger door apart and discovered why its lock wasn't cycling.
Here is what I found and what is left of the assembly. Wonder why it didn't work?
Seems like a solid repair...............lol



Cheers
B ernie

 

Hey Guys,

Checked all the blue relays but still need some info on getting the black ones off in the engine bay to check those as well.

The latest update is that ALL blue relays work perfectly. They switch normally and have no resistance when engaged. I have been able to verify that the fuel pump does run and primes. First I bypassed the relay that was in the trunk by bridging terminals 30/87 in the socket and it was clear the pump was running. Then I replaced the relay and had my son cycle the ignition and I could hear the pump priming. This is fantastic news as it now has been brought down to just a starter motor issue. Whew!

Now that I have isolated it just to the starter, I will try some things tomorrow if I have some time. Still thinking it might be the key / ignition cylinder. My one and only key doesn't work very well in any of the locks actually so I am thinking I am going to keep my eyes open for a complete set of door / column and trunk.

Onward and upward!

 

Nice one, good news.....

Keep at it & hope to hear

 

if memory serves me right. the black relays are held on by metal clip. you can pull them upwards to release. when you test the starter relay if its found good, have your helper hit the key while you chek if there is signal going into the relay. if there is no signal then you could be right about the key cylinder but there is the BPM aswell. hopefully you find the relay to be the issue. goodluck

 

Thanks for the reply.

Do you know if it is possible to test the starter by bridging the relay socket like I did with the fuel pump?
I assume its possible from what I have read. Is the relay a four or five poster?

Also, is the solenoid for the starter on the starter itself or mounted somewhere else? The I ask is because my car is parked in my inclined driveway so jacking it up to get to the starter is not safe. If I roll it to the street I will never get it back up the driveway again. Basically, I need a way to bypass the keyed ignition just to see if I can hit the starter. Hopefully through the relay if not solenoid or some other method.

Which side of the engine is the starter mounted? Again I can't get far enough under there to see it and jacking it up at this point is not an option. You can see the incline of my driveway from my original pics.

Cheers
Bernie

 

Yes you should be able to bypass the starter relay in the same way.

Yes the solenoid is on top of the starter. The starter is on the inlet manifold side and is near the top the the bell housing. You may be able to get to it from the top depending on how long and bendy your arms are!

If you haven't already downloaded the manuals then I would say it's a must. The full factory electrical diagrams are available as a link in the FAQ section. They look a tad daunting initially but are actually quite logical and quite thorough.

In the mean time, here is some info for the starter relay gleaned from the manual

Solenoid supply comes from fuse 3 in LH Engine bay fusebox (Brown White) permanent - 12v
Relay supply comes from fuse 12 RH Engine bay fusebox (White Black) key pos 2 - 12v
Realy switching is switched earth (Key pos 3) from Body Processor module via Park/Neutral switch (green orange).

Hope this helps.

 

Extremely helpful - Thanks!

I did download the electric portion of the manual yesterday.
Lotsa stuff in there that I hope I don't need........lol

Today I will check the voltages at the starter relay to see if the relay is getting its constant 12V and then the switched circuits. If it gets all the necessary voltages in P2 on the column, it may even be a bad starter itself. Going to then bridge the circuit to the solenoid and see if it turns over.

Thanks a bunch!

 

Hi Bernie, the P is supposed to be illuminated, My Jag does not start until it is illuminated, sometimes it's not, but after a good juggle it does.

My bet's on Electrical problem here. You should start with relay's.

 

Thanks Alex.

Already confirmed that the P is illuminated, the inertia switch is good, fuel pump primes, etc.

Just checked the starter motor relay and it is also showing as perfect.
Going to do some socket testing now to see if voltage is hitting the relay from upstream. If it is, then we know that I basically have a bad solenoid or a bad starter - one and the same.

Cheers
bernie

 

Hey Guys,

I hope all of this information is useful to someone else down the line so that's why I am making another post. I am working on two things together here one being the no crank issue and the other my doorlocks. Lets start with the doorlocks because they are a little related.

I discovered that the entire lock mechanism in the passenger door was fubared. Inside the motor for the door lock is a little button. This is obviously to notify the system that the door is in a locked or unlocked position. I remembered now a similar thing with the door locks on my Porsche. If, for any reason the system detects a door that's incapable of locking for any reason, it would cycle the locks a few times to try again and then ultimately time out. Same deal here. I put a jumper across the terminals where the button would have been seen from and voila, doors lock with single key turn. Now they cycle when I open it now because I would have to remove the jumper to allow them to open. The system is seeing a lock that doesn't open when the jumper is in place so it cycles it a few times and then times out. So I have the same but exact opposite with and without the jumper. Buying a new door lock system off ebay and that should correct the issue permanently. The passenger rear door also does not lock or unlock automatically so I need to take down one more door panel to completely ID all the issues.

Now on to my testing results with the no crank issue.
A poster told me that the relay for the starter is in the 4-bank of relays behind the left headlight and closest to the radiator. I was able to get the relay off (thanks for the help on that, they simply need some love to push them off the metal holder - no clips or locks). I tested the relay itself and it is perfect. The relay itself is a 5-pole relay but pole 4 is not used. There is no wire leading to it from the socket so only a 4-pole setup for the starter.

First I tested the relay and as I said it is perfect. Next I started checking the socket. First with the key off and removed. The results I got were what I expected.
Pin 1 & 2 are for the coil in the relay
Pin 1 = 0V
Pin 2 = 0V
Pin 3 & 5 are the relayed pair
Pin 3 = 12V
Pin 5 = 0V

This is what I expected to see.
Next I put the ignition key to position number 2 - right before the starter. The findings were NOT what I expected to see?

Pin 1 = 0V
Pin 2 = 7V
Pin 3 = 7V
Pin 5 = -4.3V

I put in the negative voltage value on Pin 5 because with the ignition turned off the pin was reading nothing. With the key to P2 it read this whacky reading.

For ***** and grins, I tried bridging pins 3 and 5 to see if it would hit the starter and it was just something I wasn't understanding but nope, absolutely nothing happened.

So here is where the doorlocks and no crank issue collide a little. When I tested the button for the door lock, I checked to see which side of the button was hot. I got 0 volts on one pin and on the other? I got 7V just like the relay socket.

My question now is if both are being fed from the body computer? Many questions in my head now about why the voltage drops when the car is keyed to P2? The battery in the car is smaller than needed for this car but it IS fully charged and pretty new. With no lights or starter engaged, it should have no issue handling my electrical tests.

So there is today's head scratcher.
Hopefully someone has seen something similar to this. In the meantime I will continue to search for answers myself.

EDIT - What I have not done yet is test the voltages at the socket when the key is turned and held in the start position. Need my little helper to get home for that one.

Cheers
Bernie

 

Somebody has previously suggested checking the earth leads, in particular the one from the engine to the inner wing on LH side, Have you done that? Those readings would suggest a dodgy earth to me.

Check resistance between chassis and engine block - there shouldn't be any, and directly from battery -ve to engine block if you can.

 

Thanks for the info.
No, haven't gotten to the grounds yet but I will do some quick tests to start checking some things. Is the engine to wing on the LH side easy to get to topside? Can't get under the car as it is on an incline in the driveway.

Bernie

 

Attached are some pictures of the engine bay earth points I found when doing some routine maintenance on mine

There may be others but that's all I could see in my archive pics. The picture of the empty engine bay shows the main body to engine earth strap point, and the pic of the engine shows where it goes on the block near the starter.

Note: This is RHD car so your car may be different.