Close but no cigar:

[Dave-R]

After working to revive my sunk 2011 Cobalt with a 5.7 GiC-300-P , I am stumped with only one problem. I get a EGC alarm SPN-29-FM3. It is a TCP sensor 2 high voltage alarm. It is one of the signals that control the throttle positioner. I followed the troubleshooting diagram, but with no luck. Called the dealers, and they are three weeks out. I hate to come from all the work with replacing the engine, all the switches, all the gauges, and the wife making new travel covers, and she also made new snap in carpeting, and then be held up by electronics. Well maybe next year. Dave-R

 

[gm280]

WOW recovering from a sunken boat is a huge undertaking. And even worst if you are using the sunken circuits as well. If there are from the sunken hull, you may need to get new sensors. If these are new ones already, It points to something wired incorrectly. Look to see what the sensor are doing. I mean if they are for voltage, heat, flow or what. Then see if you ground out one if that changes anything, or open the circuit or even apply voltage to one. I guess what I am trying to say is, do you know if the sensors work by being shorted, or opened or what. If you know what triggers them, then you can determine what is causing their failures.