Truck will not turn over replaced ignition switch and cylinder,its as if there is no power going to alternator. no remote start. if you keep turning ignition key it will start finally. does not happen all the time can go days no problem other days it will do it all day long.

Hello! There is a Technical Service Bulletin (TSB) # 02-06-03-006B written that addresses this issue...Dated November, 2004...It concerns the way the battery cables are connected to the posts...Loose connections cause improper battery charging and intermittent starter cable continuity....The TSB mentions that the bolt that holds the cable connector in-place is either stripped or too long...The Bulletin also mentions the charging voltage...Running voltage must be greater than engine off voltage but less than 16 volts...A function of the Alternator...If the battery is leaking, the alternator is overcharging...Take the vehicle to an authorized GMC dealer and have the TSB installed if necessary...

You can check the battery cables (both - and +) for tight, clean connections...If you have a voltmeter, set it to read +12 volts...Measure battery voltage with engine off...Record reading...Start engine and measure again...Voltage must be 1.8 - 2.0 volts higher...In both measurements place the meter probes directly on the battery post and not on the connector...

Guru...............Saailer

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