Help: 2002 C5 intermittent cranking issue

This one is probably headed for the dealer. I just haven't made up my mind whether to drive it there now (risking a monster disagnostics effort that doesn't come up with the right solution); or, waiting until
it fails completely and having it towed to the dealer. Or maybe taking it to a locksmith to check out the ignition switch.
About two months ago, the engine failed to crank on the first turn of the ignition key. Second try was successful. Acted like a bad solenoid or a dead spot on an armature. A week later it did the same thing, batt voltage was down to 11.2 volts so I threw a charge on it. Ok for several days then it acted up again. Checked all the grounds and cables between the battery and the load center. OK for several days then it failed to crank again on the first try. Replaced the three-year old battery.
Couple of weeks later I was back to the same problem. Swapped ignition keys and cleaned the contacts on the resistor bead (figuring it was a PASS key or security issue -- this car uses ignition keys like the old system on the C4). Again, things were OK for a week. Then it was sometimes taking two attempts. To reduce the accessory load when the key is turned on I started turning off the a/c before shutting down the engine.
Now, sometimes it won't crank on the first try but always makes it on the third attempt. Last Friday I was in the boondocks, miles from a tow-truck and it took four turns of the key before it cranked. That caused a 'pucker wrinkle' in the middle of the driver's seat.) For the last four days (probably a dozen starts), no problem.
Makes no difference whether the weather or car is warm or cold. Or, where the steering column is positioned.
If I recall correctly, 2002 has multiple modules whereas 2003 & '04 have a less complicated system.
Anyone else had this problem? Any thoughts?
tks in advance
-- pj
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something bad in the charging system maybe?
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wrote:

Do you use the accessory connections under the passenger side kick panel? The reason for asking is I use them and it adds a delay to the starting sequence. It is really kind of weird when you turn the key and nothing happens. I have to turn mine and hold it (for what seems like forever) and it finally starts. The computer has to check the line before it will allow the starter to continue
2001 Black Coupe
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PJ wrote:

Had the same problem about a year ago with my 02 C5. A new starter cured it. It was probably just the solenoid but I couldn't find that part by itself.
The clue was when a friend with good hearing heard the Theft Deterrent Relay click as I turned the key. That relay is in the pass footwell and has to function for the starter to turn. I have since heard that many C5's with this issue are fixed by tightening the + batt cable where it hooks to the solenoid. HTH
Don
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Don wrote:

Do you use the accessory connections under the passenger side kick panel? The reason for asking is I use them and it adds a delay to the starting sequence. It is really kind of weird when you turn the key and nothing happens. I have to turn mine and hold it (for what seems like forever) and it finally starts. The computer has to check the line before it will allow the starter to continue
2001 Black Coupe
Thanks guys,
When this happens I'm hearing a brief sound right after the key is turned -- thought it was an air conditioning actuator but it might be that security relay.
I'm using the accessory circuit to run a Garmin.
So, will leave the accessory circuit off for a while and check out that batt connection.
Tks again -- good info.
-- pj
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