My Girl has been in storage for a couple of years, in an attempt to start her up for use, she started cranking in the run position instead of the crank position and doesn’t change in crank position 3 either. I swapped relays, checked fuses, remote tested the starter, replaced the ignition switch and the BPCM, and still have the same problem. I did notice that the high beam indicator is on during the cranking event, all the gauges read good. I’ve been searching the forum for someone with a similar issue but haven’t come across any information. Please help. My Dad is unable to care for my Girl any more. He was responsible for starting the car occasionally and keeping the battery charged so I can use her when I come to visit my dad. Thank you for the help. Lady P was originally helping me trying to start my Girl from a couple of years ago and now that I am back in the Country I am giving it another try because I couldn’t continue working on her with the limited time I had to be here with my Dad.

 

Sounds like your starter solenoid is sticking. When you turn the key to the crank position, a coil on the solenoid which is attached to the starter motor is energised. This throws a cog forward onto the flywheel, connecting the starter to it, and causes the starter motor to turn. When the engine starts and you release the key, the energy is removed from the solenoid, and it returns to rest. If the solenoid is sticking, the cog stays in the forward position, which also maintains the power to the starter motor, hence the continued cranking.
I haven't had the need (touch wood!) to remove my starter, so don't know for sure, but solenoids can usually be dismantled and cleaned which should solve the problem.

 

Thank you very much, I’ll give that a try.

 

Pulled out the starter, replaced it and retried, no change, still cranks in run when attempting to start her. The old starter had some gear wear, solenoid was definitely not rusty or stuck. Tested out “Pass” at Autozone , I watched as the test was done. I swapped out the original Body Processor Module ( it had the replacement ) to see if the original module was going to work, the starter doesn’t do anything with the original BPM.
What next ?

 

Well members, it has come down to this. Body Processor Module has failed, CKPS has failed, Starter was damaged. I will be removing the Trans Rotary Switch from my Girl for an inspection and cleaning, because as strange as it seems, while I was investigating all the wiring related to the reason why it was starting in the run position and not in neutral, I followed some wires down to the transmission. I proceeded to tap on it with a hammer, and VOILA !!! It only cranks when you turn the key to start position, and it also fired up. I spent some time cleaning her up for a little drive, got in, turned the key and it started cranking in the run position again and at the same time it was running, the starter was going, until I shifted down out of Park. After 3 tries, I quit forcing the issue. Is this a unique issue , or am I chasing after the wrong thing ?

 

I was looking in the manuals at the function of the Rotary Switch on the transmission. It sends output to the decoder module next to the shifter, and to the Transmission Control Module. The decoder tells the TCM which gear is selected, and can inhibit the starter if not in P or N. It also lights up the gear indicator. That is all related to starting and driving, but shouldn't be related to the starter engaging while only in the "run" mode. So, if your gear indicator light is correct for where you position the shifter, and the car cranks ok in Park and Neutral (despite cranking in the "run" position), then the Rotary Switch is probably just fine.

Are you sure that the new ignition switch was installed correctly and without accidental shorting of any terminals? It seems like a short to the "crank" position contact could activate the starter from the "run" position. It is hard to say if this is the effect you would get if that were true, but worth checking the ignition switch. Aside from that, I would suspect the BPM again.

Let's say that the hammer tap temporarily corrected the original problem. Now, if the engine is running with the starter still engaged on the flywheel, but then the starter releases when you put the car into gear, it seems like the starter is not retracting with enough force. The retraction force comes from a spring inside the starter, or possibly only from the solenoid. So when you shift into Drive, the drop in RPM allows the starter gear to disengage due to the reduced force and friction between the two gears. It's a theory. Again that points to a worn out internal spring or solenoid on the starter.

 

Thank you SleekJag12 for your reply. The ignition switch checks out fine. I let the engine start while in the run position without having to move it to crank position, and after it starts, I quickly move it from Park to Reverse and the starter disengages as it should once started, however, now when I move the shift select from reverse to drive and back, it occasionally engages the starter when I pass the neutral position. In order to turn the engine off, I must have it in any location but Park. While it was off, , I moved the select to Neutral, turned the key to Run, and the starter doesn’t engage until I turn it to the Crank position. This is the reason I believe it is the Rotary Switch. Something has gone wrong inside the Switch that’s stuck in the Park contact. I have only one week left to find out because I have to go home from my visit with Dad. So during my last week here, I’ll be removing the Rotary Switch to open it up to look inside for the problem, but if I find nothing wrong with it, it will go back together and that will be the end of it until I can work on Her again.
p.s Starter, Crank Position Sensor, Body Processor Module,Battery,Ignition Switch,and all related Relays & Fuses have been replaced. When started She runs great.

 

I agree with @SleekJag12 , I don't see how the rotary switch could initiate cranking.

I can see that you have replaced many parts but some more detail diagnostics is what is really needed here. From looking at the Electrical Guide, there are only really two things that could cause what you are describing. I would do the following tests to diagnose.

1. The ignition switch and the wiring from the switch to the BPM. Test at the BPM for ground on Pin FC2-41. If you have ground signal here when the key is not in position III then the fault is either the ignition switch or a short to ground on the wiring between the switch and the BPM.

2. Assuming 1. does not find the problem, check Pin FC1-33 on the BPM. This should only have a ground when key is in position 3. If you have ground on this pin, but not on FC2-41 (as in 1. above) then the BPM is faulty or there is a short to ground on the wire from that pin to the starter relay.

I think the problems lies in either 1. or 2. above. There is a possibility that there is an issue with the actual starter relay or it's wiring but if that was the case I don't think cranking would stop when you move the selector.

EDIT: Note also that Key Pos III signal to the BPM is also used to turn off the Interior lights (during Cranking). If your lights are off at Pos II then that is further evidence of the Ignition Switch or it's wiring is not right.

 

Problem Solved. Transmission Rotary Switch had internal damage. At some point, heat softened up the Contact Bar to the circuit board and when it was shifted from Park, the dried up bushings were slow to rotate with the transmission and thus twisted the contact bar and closed the contacts and a short situation occurred. I opened up the switch to find this out and saw the internal damage and the dry binding bushings that caused the problem. I cleaned up the circuit board and contacts, used a heat gun to soften the rotating part back into the original position, put Crazy Glue in the plastic to metal where it was broken loose, reassembled it, and it works as it should now. I hope this information will help others that may have a similar start problem. Thank you to all in your efforts to help me.

 

Transmission Rotary Switch was distorted because the bushings inside that allow it to rotate smoothly when the shifting was done were dry and binding, this caused the plastic Rotary plate to distort the metal contact plates and shorted the information to the BCM thus engaging the starter before the key was turned to the crank position and began its sequence in Run. I found this out upon opening the Rotary Switch to look inside because it was the only thing left to check as I followed the wires from the inside to the outside. After discovering the tweaked contact, I proceeded to clean up the dust off the board and connections, then I took a heat gun to the contact bar to soften it up to return it to its original position and then used Crazy Glue to hold the part that separated together. I drilled out the broken screws from the case, lubricated the motion points but not the contact points, closed it up with a little silicone sealer and rivet the case closed, installed it in the position it was removed from, and it works as it should. I hope this will help out others that may experience the problem of cranking in the run position. Thank you to all that provided information on what to look for and test in an effort to resolve my dilemma. I was told that it was unlikely to be the Rotary Switch, but it proved to be otherwise. Thank you to jaguarforums.com for being here for me.

 

Pic of what Zorro was going through to resolve his issue :

The starter relay ( termed starter solenoid ) is looking for a ground path through the BPM on the blue colored wire to command the relay closed to engage the starter

The damaged rotary switch provided that ground through the case of the switch

 

Zorro,

Congratulations on successfully resolving your issue! I have moved your most recent post on the resolution to this thread so the full story will be together in the same thread and I have edited the thread title accordingly.

Cheers,

Don