5.7 GXi-C in engine protection mode

[Tristador]

Hello all,
I have a 2011 Stingray 250 CS with a 5.7 Gxi-C P . Serial number A152226
The engine is going into protection mode at 1000 rpms. The engine will not go above 3000 rpms.
The Check Engine light does not come on, only the red triangle with one beep.
Returning to idle speed, the fault clears itself.
I have been reading the many informative posts on this forum and have learned a lot , but I am not able to identify the cause. I just purchased a RInda TechMate Pro scan tool. It didn't show any active faults upon connection.
It shows Derate 1 ON when the RED Triangle is lit. Soft Warning output On.
Engine temperature and oil pressure readings are good, according to the data on the tool.and
no misfires detected.
Can anyone point me to what data I should be looking for ?
There is so much information on this tool and I don't know what to do with it all.

Is there anyway to store the data and print a report ?
Thanks in advance for any help.

 

[alldodge]

Don't know if your motor has an in-gear switch. If it does the PCM may think its in neutral and will not let the motor rpms increase.

 

[Tristador]

Alldodge,
You may be on to something, Watching the Rinda screen, as soon as the IVS State reads Off-Idle, I get one warning beep and the red warning triangle lights up. Derate activated at that time.
When I throttle back to idle, the fault clears as soon as the IVS state is Idle.
This was just done while docked, moving the throttle with the gear disengagement button pushed so i could control throttle only.
I'm going to do some reading up on the Idle Validation Switch and see what i can find.
Thank you for the tip.

 

[Tristador]

I took the boat out for a ride today, clearing all stored trouble codes so I would be dealing with fresh codes and not some that had built up over the years.
I got some hard trouble codes now. MIL is lit and beeping. Engine likes to stall at low speed, almost idling.
.
IWith the scan tool, I pulled 5 codes.
The codes are all listed as SPN, I need to dig deep and find out what these mean, but they do seem to lean to the Throttle position system and sensors.

SPN 3673 FM 4 Count 3
Engine TP sensor 2
voltage below normal or shorted low.

SPN 1079 FM 4 Count 2
Sensor Power Supply 1
evoltage below normal or shorted low.

SPN 91 FM1 Count 13
Accel pedal/lever snsor 1
data valid but below normal range

SPN 91 FM4 Count 2
Accel pedal/lever sensor 1
voltage below normal or shorted low

SPN 91 FM18 Count 9
Accel pedal/lever sensor 1
data moderately below normal range

Anyone have any info or sources to pass along that could help me solve this issue?
I will be posting my findings to this thread as I get them.
TIA
Tristador

 

[alldodge]

Two codes showing voltage below normal
I would start measuring alternator output and could be there is a ALT or battery problem

 

[Tristador]

I got these codes to clear.

It turned out that I had a problem with the 5V system shorting to ground.
Thank you for your assistance.