Charging at idle, oem idle parameters, what charging we can tune.

[Speedz06]

I'm learning this stuff day by day but help would be appreciated greatly. Anyone know what the alternator table should look like, im thinking mine is not right

I'll search threads but if anyone knows this well please let me know.

My setting for
1. Voltage control: Not Fitted (Im thinking it should be "fitted?")
(ECM 740) " Alternator Voltage Control: Indicates the vehicle is fitted with a regulated voltage control alternator and serial message duty cycle control from BCM is available, if disabled DC will be 100% when alternator is enabled."

Firstly, on the most of the tales on HP Tuners tables each has an ecm code number. For instance in reference to the above voltage control, what does "ECM 740" mean? is this some reference where I can look up more info or a circuit number? Is there a way to look up info using these "ECM #'s"


This above "Voltage Control" parameter determines the status of the next parameter:

2. ECM override 741) "Disabled" (thinking it should be "enabled" not sure) ECM override cannot be enabled unless the above table has "fitted"

"Alternator ECM Override: (notes) Should only be enabled if Voltage Control is enabled. Indicates that the ECM can override the serial message alternator duty cycle to boost system voltage when required."

I would think that we would want that "ON"?

Doesnt this mean that the ECM will NOT increase voltage as necessary when it sees a need to increase voltage?
This makes sense then that mechanic at the shop was thinking the computer isnt telling the alternator to add voltage when needed. Maybe he just wasnt looking here since no one would normally turn that off.

Can I command the alternator to supply 14.2-14.7 at idle, which it is perfectly capable of IMO. then, amperage draw will actually reduce. The alternator will run cooler, everything will have more juice...

[???]

anything ever come of this?

[[email protected]]

Anything?

[???]

on a 08 c6 I tried changing to fitted and enabled and the alt wouldn't charge at all. so I put it back and messed with some some of the voltage values in the boost settings and nothing I did seems to change anything.

when I'm watching the voltage it sure seems like the ecm is controlling it, but it no setting changed anything besides not working at all.

all id like to do is have the car idle itself up to keep the voltage off the battery when it's hot and everything is running at max. my amp clamp says the output is bouncing between 50 to 70 amps out at idle, but it's just not enough to keep up with 110 deg summer traffic. I don't really wanna idle the car up to 1000rpms or over drive the alt all the time. but as is, it just can't keep up and I can't find anything in the settings to adjust idle based on voltage. even old obd1 ecm have a rpm vs voltage table. so annoying.

[ke5gnz]

the BCM tells the ECM when and how much the alternator needs to charge. no setting in the ECM will change the charge rate, and unfortunately we cant change the BCM

[???]

the BCM tells the ECM when and how much the alternator needs to charge. no setting in the ECM will change the charge rate, and unfortunately we cant change the BCM

probably can't tell much from a pic of the diagram but the BCM (top right) only picks up the system voltage from fuse 15 and puts that voltage over the serial data line to the ecm. the ecm is what outputs the generator field duty cycle signal from the settings. I'm just not sure hp defined them correctly for this car's os. since the setting default to not fitted even thou it shows in all the paperwork that it's wired like that. I will probably look at the duty cycle at some point when I break out a scope to look at it.