The earlier (PTEC aka PCM150) can't be reprogrammed so you can't swap a used one in. (Obviously with the right knowledge someone could in theory reprogram one but not with Jag tools.) Repairers should be OK.

Agreed - finding the actual problem would seem wise LOL

 

The car sat for a while as we had a lot going on. We have finally got back to it and determined that it was damaged contacts on the wiring connections to the ECU. The car is running nicely now and I am in the final stages of putting it through the roadworthy process.

 

I see you changed the wheels. Glad you got it fixed ok. I wondered if that was a stupid place for them to put the ECM connections; right underneath a big funnel that when blocked will submerge the connections! Obviously, it is possible for water to damage them.
Who designs this stuff? Kindergarten dropouts?

 

The car has passed a roadworthiness test now and been re-registered. Forum members in Victoria, Australia might see us driving it now.

 

Long time but you got it fixed! Thanks for coming back to help the next guy too!
Any pictures of the damage? It can range from minor to completely eat up.
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And again I fell for it - I started reading everything from the very start, not realizing that this is not a new post, but 2 years old.
Anyway - I am not lying here: After one of your first posts, where you listed, what the previous mechanic-owner did already, I was about to write the following to you (again - thinking that this is a current problem):
Looks like the mechanic checked already many suspicious components and went on looking for the next possible failure source. But what he probably did not check is, if there is a problem in the wiring, or more likely a corroded or worn out contact pin in one of the many connectors, big and small. I just found one of those tricky faults in my Jag causing the ABS check light to light up...

 

Would the CPK throw a code from a failed attempt at starting? In this case I am referring to a 2000XKR.

Thanks

Tom

 

Typically not. The OBD II system is designed primarily for monitoring and reporting faults related to emissions. If you have a fault preventing the engine from starting, in the OBD II mindset, that's not related to emissions. Even if the computer knows why the engine won't start (a required input is missing or invalid, for example), it won't tell you via the OBD II interface. It's kinda like getting in the wrong line at the DMV office. Even though the slug lady behind the counter can access the entire computer system from any terminal, you wanted a new driver's license but are in the line for renewing vehicle registration. She crosses her arms and isn't going to offer the information you need.

 

Most (?) S-Types will log P1582 (a data recorder) for a start / sudden stop issue but an ordinary OBD tool doesn't know how to decode it.

 

I beer had a start/stop problem on my S-type *although my question was about the 2000XKR( but will see sometimes a 1582 that I use the SDD to erase- since I have no other codes to go with it and as a consequance will not worry about data that will have no meaning to me.

T

 

There are codes for a malfunctioning CKP, but you are indicating that will not be seen as you attempt to start the car that will not start?

TBB

 

That's the way I understand the situation. How the computer decides to tell/not tell us something? It can be a mystery sometimes. The OBD system is primarily geared towards reporting emissions-related faults. We can use the system to our advantage when troubleshooting, but like any diagnostic tools there are limitations.

For example: Say we've got a rough running engine with low power on one cylinder, with a clogged injector as the root cause. In such a case, emissions also increase and the OBD system gladly reports which cylinder has low power output. We still have to troubleshoot if it's a bad coil, spark plug, low compression, etc. But in most cases, OBD codes will steer us in the right direction towards a fix.

What about a no-start? Or maybe an engine just died suddenly out of the blue? If it's not emissions-related, there often isn't a fault code set. The computer may well know what's wrong, and dealer-level software may be able to retrieve additional details. But unfortunately such info isn't usually available to us mere mortals with our garden variety scanners. We can wish the situation was different, but that's just how it is.

On a related note, I just noticed an interesting tidbit for code P0335 (CKP sensor circuit malfunction) here:

http://www.jagrepair.com/images/Auto..._OBD_II_R2.pdf

"Note: If CKP Sensor fault exists, engine will start after approximately 5 seconds of cranking as the ECM will default to CMP Sensor 1 signal for synchronization."

Reading between the lines, for a no-start condition and the CKP sensor is suspected, crank the starter for at least 5 seconds and see if the engine now starts. I do not know if this switchover logic only happens if P0335 has already been set, or if it would happen anytime the CKP input is invalid, even without a code.