Low voltage.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Here ya go,,, try this
Get a set of JUMPER CABLES and pick a color,,, RED or BLACK.. What ever color clamp that you pick, put one clamp on the POSITIVE Battery terminal and the other one on the terminal on back of the alternator
See if it starts charging.
Get a set of JUMPER CABLES and pick a color,,, RED or BLACK.. What ever color clamp that you pick, put one clamp on the POSITIVE Battery terminal and the other one on the terminal on back of the alternator
See if it starts charging.
Last edited by Bill Curlee; Aug 14, 2013 at 06:04 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
With the engine OFF,,, you SHOULD have battery voltage on the BATT terminal. Its connected directly to the battery thru the starter solenoid. If you truly have 0 volts,, your fuseable link is most likely blown.
An ohm meter reading from the removed POS battery terminal to the BATT terminal will most likely show INFINITY or OPEN
BC
An ohm meter reading from the removed POS battery terminal to the BATT terminal will most likely show INFINITY or OPEN
BC
Thread Starter
Racer
Joined: Dec 2012
Posts: 254
Likes: 1
From: Midland TX
I took it in to the dealership today and they put the scan tool on it. It is showing the pcm terminal (not sure if that was the proper term) L is not functioning correctly. F is told that the alternator needs to charge the battery and L is supposed to excite the alternator to actually do it's job which is not happening. So basically the pcm is being told that the alternator needs to turn on but the command to start charging never reaches the alternator. He told me it is either the pcm Itself, a loose connection going into the pcm, or a bad ground somewhere. I am taking it back there Saturday morning to have him work on it and get it fixed! I will let you guys know what I find out at that point! Thank you for all of your help and suggestions guys!
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 461
From: Southern Utah
I agree with Bill...I can't understand how there would not be battery voltage at the alternator output terminal when it is connected directly to the battery with a simple wire. That fusible link looks to me like at least part of the problem.
Thread Starter
Racer
Joined: Dec 2012
Posts: 254
Likes: 1
From: Midland TX
I agree that it is definitely odd that it shows 0v instead of showing the battery voltage. I checked the fuse and it is still intact and even swapped it to just be sure. I checked the resistance of the battery wire going to the alternator and it showed 0 ohms.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Well,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, before you spend $$$$$$$$$
$$$$$$$$$$$$$ at the dealer,,, please try jumpering the battery POSITIVE terminal to the alternator BATT terminal and see if you charge again..
It wont hurt and it may resolve your issue!
I dont trus STEALERSHIPS as far as I can spit.
$$$$$$$$$$$$$ at the dealer,,, please try jumpering the battery POSITIVE terminal to the alternator BATT terminal and see if you charge again.. It wont hurt and it may resolve your issue!
I dont trus STEALERSHIPS as far as I can spit.
Moderator emeritus
Joined: Jun 2001
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Well,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, before you spend $$$$$$$$$$$$$$$$$$$$$$ at the dealer,,, please try jumpering the battery POSITIVE terminal to the alternator BATT terminal and see if you charge again..
It wont hurt and it may resolve your issue!
I dont trus STEALERSHIPS as far as I can spit.
$$$$$$$$$$$$$ at the dealer,,, please try jumpering the battery POSITIVE terminal to the alternator BATT terminal and see if you charge again.. It wont hurt and it may resolve your issue!
I dont trus STEALERSHIPS as far as I can spit.
That's too much trust.
There seems to be an open between the alternator and the battery.Elmer
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Something is wrong,, because, if the wire with the fusable link was good,,,,,,,,,,, you would have battery voltage at the BATT terminal without a doubt!
jumper that wire!
and I bet thats your issue!
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Thread Starter
Racer
Joined: Dec 2012
Posts: 254
Likes: 1
From: Midland TX
I checked the fuse and it is still intact and even swapped it to just be sure. I checked the resistance of the battery wire going to the alternator and it showed 0 ohms
Something is wrong,, because, if the wire with the fusable link was good,,,,,,,,,,, you would have battery voltage at the BATT terminal without a doubt!
jumper that wire! and I bet thats your issue!
Something is wrong,, because, if the wire with the fusable link was good,,,,,,,,,,, you would have battery voltage at the BATT terminal without a doubt!
jumper that wire!
and I bet thats your issue!If the wire has a 0 ohm resistance wouldn't that mean the wire is good? I would be over joyed if it was only a bad wire and that fixed it! If it is a bad wire then why is the pcm throwing codes?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If the battery terminal has 12.VDC on it,, the BATT terminal on the back of the alternator SHOULD also have 12 VDC.
If it doesnt, your ohm meter is lying to you!
Like I stated before, it take 2 min to connect a jumper and its FREE!
7th Gear
Joined: Apr 2018
Posts: 7
Likes: 0
From: Columbus OH
Any update on this situation? I have the same problem and this thread is the closest to what I have going on. Very curious about what happened or what the issue was. Thanks!
7th Gear
Joined: Apr 2018
Posts: 7
Likes: 0
From: Columbus OH
Low voltage at high temps, when stopped, and slow/no crank when engine is hot
For the next person with an C6 LS2 trying to fix the voltage flux at high temps seen in traffic jams, drive throughs, or slow/no start when the engine is hot. The low voltage has been sending "Service Charging System" when dipping below 13.5 volts and hitting as low as 11 volts before jumping back up to nominal. Also experienced no start/crank when hitting the start button until the engine cools down enough and suddenly a slow crank will get the car started.
replacement solenoid can be found on Amazon for ~$25 search:
"DB Electrical SDR6160 Solenoid Compatible with/Replacement forDelco PG260H, L Starters, 12 Volt /10503939/10-DE263, 10-DE263S, 10-DE269 /RAD126"
This is a direct replacement for 'AC Delco 10503939' which is on my 2006 LS2 C6 manual (I don't think that matters but I see people always asking on tranny type).
I have Kooks long tube headers which need to be loosened (I took the 5 or 6 bolts completely off the block & 2 bolts connecting to the x pipe below) to allow the header to be free. That being said, you'll have to remove the fastener securing the oil dip stick to the block that is at the header bolts as well as the x4 ignition wires to get access to the starter from the top. This is necessary to access one of the 2 bolts holding the starter to the engine block (at least with long tube headers). *DISCONNECT BATTERY, there is a straight connection from the batt to starter which will rock you if its left live and you create a ground for that stored electric* Disconnect the oil temp sensor, loosen the x2 starter bolts, using a flat head or a slim hand, disconnect the wiring connector (the connector's lock is at the top end of the connection; just lift up to unlock then pull toward the front of the car to disengage. After confirming battery is disconnected, undo the nut that holds the battery connection to the starter. completely remove the x2 starter bolts you previously loosened, twist and pull out the starter. you'll have to use a 5mm or 5.5mm hex to remove the x3 fasteners securing the solenoid to the starter as well as the electrical connection between the starter and solenoid.. which is 1 nut.
Keep in mind that TQ spec for these nuts on the solenoid are around 7ft/lbs so it'll feel like its finger tightened. I tried using a heat shield but the stock battery cable was too short to reach around the heat shield so I didn't use it. The product was on Amazon "Polished Aluminum Fits Chevy Compact Mini Starter Heat Shield/Cover" and fit the starter on 2 of the 3 mounting points to the starter but again, the C6 LS2 2006 battery cable to the starter is too short to reach around the heat shield.
To install, set the starter into position where it'll be fastened to the block. Before fastening, tilt starter up and reconnect the electrical connector and the battery cable to the starter. then install the x2 starter bolts to the block. Reconnect the oil temp sensor you previously removed. Begin to install the header bolts to the block but don't tighten. Completely tighten the lower end of the long tube headers to the X pipe then completely tighten the headers to the block. Fasten the oil dip stick back to the block, reconnect the ignition wires, and finally reinstall the battery.
Hope the amazon products help. Sorry for the "spoiler" I have no idea how to delete it from this post? The ~$25 solenoid is much better than buying a complete starter in my opinion but others will suggest swapping the entire unit. I'm just a cheap ***. More money for gas and tires 
replacement solenoid can be found on Amazon for ~$25 search:
"DB Electrical SDR6160 Solenoid Compatible with/Replacement forDelco PG260H, L Starters, 12 Volt /10503939/10-DE263, 10-DE263S, 10-DE269 /RAD126"
This is a direct replacement for 'AC Delco 10503939' which is on my 2006 LS2 C6 manual (I don't think that matters but I see people always asking on tranny type).
I have Kooks long tube headers which need to be loosened (I took the 5 or 6 bolts completely off the block & 2 bolts connecting to the x pipe below) to allow the header to be free. That being said, you'll have to remove the fastener securing the oil dip stick to the block that is at the header bolts as well as the x4 ignition wires to get access to the starter from the top. This is necessary to access one of the 2 bolts holding the starter to the engine block (at least with long tube headers). *DISCONNECT BATTERY, there is a straight connection from the batt to starter which will rock you if its left live and you create a ground for that stored electric* Disconnect the oil temp sensor, loosen the x2 starter bolts, using a flat head or a slim hand, disconnect the wiring connector (the connector's lock is at the top end of the connection; just lift up to unlock then pull toward the front of the car to disengage. After confirming battery is disconnected, undo the nut that holds the battery connection to the starter. completely remove the x2 starter bolts you previously loosened, twist and pull out the starter. you'll have to use a 5mm or 5.5mm hex to remove the x3 fasteners securing the solenoid to the starter as well as the electrical connection between the starter and solenoid.. which is 1 nut.
Keep in mind that TQ spec for these nuts on the solenoid are around 7ft/lbs so it'll feel like its finger tightened. I tried using a heat shield but the stock battery cable was too short to reach around the heat shield so I didn't use it. The product was on Amazon "Polished Aluminum Fits Chevy Compact Mini Starter Heat Shield/Cover" and fit the starter on 2 of the 3 mounting points to the starter but again, the C6 LS2 2006 battery cable to the starter is too short to reach around the heat shield.
To install, set the starter into position where it'll be fastened to the block. Before fastening, tilt starter up and reconnect the electrical connector and the battery cable to the starter. then install the x2 starter bolts to the block. Reconnect the oil temp sensor you previously removed. Begin to install the header bolts to the block but don't tighten. Completely tighten the lower end of the long tube headers to the X pipe then completely tighten the headers to the block. Fasten the oil dip stick back to the block, reconnect the ignition wires, and finally reinstall the battery.
Spoiler