Service code issue
Thread Starter
5th Gear
Joined: Oct 2021
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Service code issue
We have a 2006 C6 that had headers and high performance plugs installed. Our BCM failed recently and after replacing it, we still get an service charging system code. Dealer says it’s the plugs. We’re reluctant to go back to OEM, because we think the engine is tuned to them for the headers. Thoughts?
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,508
Likes: 4,000
From: Cape Coral, Florida
We have a 2006 C6 that had headers and high performance plugs installed. Our BCM failed recently and after replacing it, we still get an service charging system code. Dealer says it’s the plugs. We’re reluctant to go back to OEM, because we think the engine is tuned to them for the headers. Thoughts?
Last edited by C5 Diag; Oct 4, 2021 at 01:52 PM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,508
Likes: 4,000
From: Cape Coral, Florida
I found something but not the whole TSB...you using NGK or these E3 plugs ??
PIC4536C: Service Charging System Message On DIC And DTC P0621 - keywords charge fuse generator horn lamp light open - (Dec 3, 2008)
Models: 2005-2009 Chevrolet Corvette models
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may comment that the Service Charging System message displays on the DIC.
Using the Tech2, DTC P0621 is stored.
This may be a result of aftermarket spark plugs or an open in circuit number 2540.
Recommendation/Instructions:
Check for aftermarket spark plugs on E bay.
Plugs that are designed with a "Pulse" technology will interfere with this circuit and cause the Service Charging System message to illuminate on the IP and/or P0621 DTC store in the ECM.
If aftermarket plugs are installed, replace plugs with OEM parts.
This is not considered a warranty repair and all cost associated with this repair should be the customers responsibility.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,508
Likes: 4,000
From: Cape Coral, Florida
Would have been easy for the Dealership to tell you if the plugs you had were the ones mentioned in the TSB…hopefully your Tech can do a quick charging system test..doesn’t take that long !!…let us know what you find !!
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