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Not so much as a couple minor hiccups all these years. Strange thing this morning. Got in, started car, backed out of garage and waited for Mrs to lock the house (engine running). All of a sudden the car shuts off. Tried starting, no crank (Maybe CPS?). After a few car restarted and drove to Dr appointment. After Dr appointment stopped at Walmart for some shopping. Loaded car, started car, after about 30-35 seconds BAM, car shuts down. Tried starting again, nothing, no crank. After a few tried my backup NEW RCM, car started again and within 30-35 seconds shut down again. I had just purchased refrigerated items and thought wasted $'s but after a couple more times of starting car and it cutting off, it stays running. Made it home with groceries and here I am.



So, this is not the SKREEM, never had to take off the battery cable. Not RCM, new one did same thing (no crank and when did start ran for @ 30-35 seconds and then cuts out). I am leaning to CPS BUT doesn't it still crank when the CPS is acting up?

I have not tried to access any codes yet.


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It might be the CPS. Engine was running when it shut down, cps stays hot, cools down and you can start it. Heats up, then shuts down again.
Cheapest fix to try. If the new CPS is installed and it still does the same, you will have to check for codes.

 

The CPS will not stop the starter from engaging.

Here is my advice, wait for this to happen again:
When the car refuses to crank, relax the key to the ON position.
If, in about 30 seconds, the engine fan warps up to high speed, then the ECU is not powered up and this is usually the RCM but COULD be a failed output from the key switch (but I doubt that).
If the fan does not speed up, I'd wonder about system voltage. Low voltage will cause the engine to cut out AND cause a no crank as well.

Usually, you'd have a battery (alternator) light in this case but not always. Also, being ready to check system voltage when this happens (carry a meter) would be helpful. Crossfires will not crank below about 10.8 volts.

That's all I can come up with.

 

You say you have never had to remove a battery cable? Hopefully it is not the original battery. I would also suspect corroded or dirty battery connections for the cables. Have you had a lot of humidity?

 

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I have taken the battery cable off, just not during this latest behavior. I also did swap the RCM but did not wait for a fan to 'warp up' after 30 seconds. Battery 12.8 volts with no engine running and key on. Car was cold out of the garage when first happened, truly a strange one here.

Will check for codes this morning, until I can figure this out the XF is parked (do not need a tow to home if stuck out somewhere).


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OK, tried the RCM test warp-up, no go. Car started again once, no codes on my CRP-123 & Crp-123E. Continues to just die with no start. Truely a wierd one here.


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Maybe something is reducing the voltage and causing the no start?
Have you tried getting any voltage readings while it was happening, as pizzaguy suggested?

 

Haven't tried the attempt to crank with a voltmeter but when it does start it cranks very quickly for about a second then starts (when it does). This voltage test will be next to try. Thanks for your replies!


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