Scurry1074,
On a conventional vehicle with an ICE, regarding the basic principles of combustion you are correct, nothing changes there with the Karma (as far as the engine running). And you're right about being able to identify the make of the vehicle just listening to the starter cranking.
I think the biggest difference you need to understand the Karma is not a conventional vehicle by any stretch of the imagination. It does not have a starter motor and it doesn't even need the engine to be running to move the vehicle.
I said all of this to get to this one point. I would like to learn more about the Karma systems and how it works. I would like a basic understanding of what happens when I get in my Fisker Karma and I push the start button what happens.
The Karma is pretty complex monster but I'll try to give a basic overview on what happens when you hit the start button. Please take into consideration that you are driving an unfinished car, and it has many exceptions or "quirks."
This is a very brief overview and has many more layers to it.
1. User pushes Start button while pressing brake pedal to enter "Ready" mode (Run for conventional vehicles)
2. VCM detects power mode request and wakes up all modules. Request for HV initialization is sent to HCU.
3. HCU detects request and if all safety and functional criteria are met, HCU sends command to BECM to close HV contactors.
4. If all safety and functional criteria are met, BECM closes HV battery contactors. Vehicle is now in"Ready" mode but with propulsion disabled.
5. User selects "Drive" while pressing brake pedal.
6. HCU detects user input and if all safety and functional criteria have been met, HCU enables forward propulsion.
How does the 12v battery interact with HV battery? If the 12v battery is discharged the Karma won't start is this because the 12v battery must initiate things first before the HV battery can take over? I’m not asking for a training course even though that’s what I might need to understand this.
All of the electronics in the vehicle are controlled by the 12 volt battery (as it is in a conventional vehicle). If the 12 volt battery is drained nothing will work. If the 12 volt battery is LOW, some things might work, others will not. For example you may be able to open the door to the car but there may not be enough voltage at the BECM to close contactors to activate the HV system.
The 12 volt battery is charged by the HV battery via the APM (accessory power module). This basically replaces the alternator on a conventional car. If you are in Ready mode (Ready light SOLID not flashing), contactors are closed and the HV battery is charging the via the 12 volt battery via the APM. In ACC mode, HV contactors are not closed and the APM is not charging the battery.
It seems that Hybrid Solutions only provided basic troubleshooting solutions to Mikey43 that any of us that’s been around this forum are all ready familiar with such as how to reset the Karma. Most of us know that this restores the Karma back to its intended function. Before I call you guys for help I would have at least done a reset.
I don't know what was and what was not discussed in that conversation and I do not know what Mikey43's level of automotive knowledge is, but I will say this: This is not an easy vehicle to work, especially if you are not familiar with it. This car has probably an infinite amount of things that can go wrong with it. For example the BECM has over 3000 types of faults alone, all with similar symptoms and that is only one module. My point is there is only so much one can do over the phone without any diagnostic tools which on this car, is absolutely critical.
As for 12 volt resets, could it have worked? Sure, its definitely possible that a 12 volt reset could have got the car going, but at what cost? Any time you disconnect that 12 volt connector, you have just lost the ability to find out
why the car would not move, so now you have a ticking time bomb (not literally). Whatever caused the problem will come back and maybe this time it won't be in a convenient location like a driveway.
On top of losing vital information, that connector is not made to be disconnected numerous times as the terminals can become loose and make poor contact with each other over time, causing intermittent grounding issues. I'm sure you're familiar with what kind of havoc loose grounds can cause on an electrical system.
Hopefully this clears up some things & it was not meant to be condescending towards anyone. Feel free to ask any follow up questions and I'll do my best to answer them.
