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1999 XJ - when is cruise control light SUPPOSED to light?

OK... I've been testing this cruise control now for 5 months and so can say with certainty now that my intermittent connection problem was due to my attempt at clockspring repair (initial problem was that someone installed a non cruise control clock spring into my Jeep which has all the cruise control components), which was allowing very brief connection breakages, and then as soon as the sum of all of those breakages exceeded ~3 seconds, the cruise control shuts down completely until you restart the engine (see detailed explanation in my previous post). To solve this problem, I just bypassed the clock spring and made sure my connections were 100% solid, and the cruise control has been working perfectly since then for months now.
The takeaway from all this is that when troubleshooting the cruise control system, you have to remember that the PCM shuts down the cruise control system completely if it sees greater than a sum of ~3 seconds of broken connection time between the steering column controls and the PCM, and that means that a condition can exist where the cruise control system is in 100% perfect operating condition including all connections, and yet the cruise control lamp will not come on and the cruise control system will not function not because there is anything currently wrong with the system but only because the PCM has seen a historic problem with the system since last engine start that lasted greater than a total of ~3 seconds, and this strange but normal PCM behavior can make troubleshooting an intermittent connection difficult because until you restart the engine you really don't know if the problem has been fixed or not. I drove around for awhile with a voltmeter connected to the PCM input for the cruise control, and the cruise control would shut down without the voltmeter indicating any disconnection whatsoever, because even extremely brief disconnections are recorded by the PCM until they add up to ~ 3 seconds and then the system shuts down until engine restart. If this PCM peculiarity didn't exist, you could get the cruise control lamp to turn on and then wiggle wire harnesses, etc., until you were able to find where the intermittent connection problem was located (because the system would work when the connection was good and not work when the connection was not good), but with the PCM recording every little minor intermittent disconnection, the PCM shuts down the system long before you have a chance to locate the intermittent connection problem, and then you have to restart the engine and try again over and over and over. The only way to troubleshoot this problem with this PCM behavior is to bypass different sections of the circuit until the system quits shutting down, and then you will know where the intermittent problem is located.
 
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