Charging System Fault
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Charging System Fault
I've noticed that the last few times I've turned on my 2004 C5 after it has been parked for any extended period, that the car is slow to crank up and on a few occasions the "Charging System Fault" error appears on the DIC. I'm the original owner, the car is not a daily driver, has around 30K miles on it and I hook it up to a C-tek tender whenever I park it for an extended period of time. I just replaced the battery which has a 14 volt charge when running. I do have a bunch of aftermarket LED lighting and upgraded stereo but nothing that would indicate a parasitic drain. Once I get past the first start, the car starts rights up after every stop when I'm out running errands, etc.
My question is whether this symptom is typical of a failing alternator, failing starter or something else? I'm planning a performance build for this winter that will include adding an A&A supercharger and headers. As part of the preventive maintenance, I am planning on installing a new harmonic balancer as well. If this is a starter-related issue, the best time to swap it out would before I install the headers.
What say you CF C5 Tech?
My question is whether this symptom is typical of a failing alternator, failing starter or something else? I'm planning a performance build for this winter that will include adding an A&A supercharger and headers. As part of the preventive maintenance, I am planning on installing a new harmonic balancer as well. If this is a starter-related issue, the best time to swap it out would before I install the headers.
What say you CF C5 Tech?
Last edited by MSG C5; Oct 22, 2023 at 06:22 PM.
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From: Cape Coral, Florida
If it’s slow to crank and not knowing how old your battery is I’d get that checked first….always start with the battery….maybe a flaky voltage regulator….what part of Florida are you in ??…if Southwest bring it by.
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Thanks. The battery is new. I just replaced it less than 2 months ago and it has a 13.5 volt at start up and 14 when driving.
Melting Slicks
Joined: Sep 2008
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From: Espanola New Mexico
From the voltage you are seeing I don't think it's a charging system problem, but I would ask you to examine the cable connections at the starter solenoid. The other test I would perform is a measurement of the cars sleep mode current drain. That measurement is done by wiring in a DVM in series with the negative battery terminal and negative battery cable, of course you have to move the positive meter lead to the 10 amp jack and select dc current on the meter. Wait 20 minutes or so, normal current drain should be about 25ma.
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From: Anthony TX
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St. Jude Donor '08
From the voltage you are seeing I don't think it's a charging system problem, but I would ask you to examine the cable connections at the starter solenoid. The other test I would perform is a measurement of the cars sleep mode current drain. That measurement is done by wiring in a DVM in series with the negative battery terminal and negative battery cable, of course you have to move the positive meter lead to the 10 amp jack and select dc current on the meter. Wait 20 minutes or so, normal current drain should be about 25ma.
I would also have the system fully checked out at the Autoparts store. Have them do a full system load test and charging system check.
I would also conduct this test. Use a Multimeter DCV on a scale that will read 0-20 VDC. Measure the BATT terminal on the back of the alternator TO the POSITIVE Battery terminal. Theoretically, and if all the wiring and connections between the battery and alternator are clean and tight, You should see zero volts. If there are any issues you will see a voltage drop reading. See what you are reading between the two points and report back.
YES,, Conduct a SLEEP CURRENT DRAW TEST. You should read 20-25 milliamps once the BCM goes into sleep mode.
Make sure that your battery terminal connections are properly tightened. The manual states 11 foot pounds. If you can ever move the battery terminals by hand, they are too loose!
What is the RESERVE CAPACITY of your new battery? The C5 should have a RC of 120 amp/hrs to be able to sit /store for an extended period of time. To get a battery that had that RC for my 02 ZO6, I had to get the next size /series battery.
Bill
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