DCH24V02

I have a 02 2500 just hit 218k mostly stock besides edge Evo ht tuner, fass DDRP, newer blue chips diesel vp44, 5" straight pipe and BHAF truck has been fine for the last 2 years. Recently Truck went into limp mode and I got codes po112 and po237 low voltage on iat and boost sensor circuits. Removed my tuner and replaced both iat and map sensor with oem cummins sensors (no change) next I cleaned all the grounds I could find and cleaned pos+ and neg- battery cables had battery's tested and alternator (no change) have good ground at sensors checked with voltmeter and also have 5 volts at map sensor. pulled ecm and checked resistance between ecm plug and sensor plugs on the harness at pin 11(ground) pin 10(5 volt supply) and pin 7 and pin 8 map and iat sensor signal wires all had good resistance. Had a DBRIII scan tool hooked up and iat sensor read 299 degrees and map showed no reading.. Don't think it's a ground issue cause 7 sensors use the pin 11 ground so I would assume if a ground issue all of them would be giving me issues? Only thing left is ecm that I can think of anyone have any suggestions or ideas before I fork out the money for a new one.. Any help or suggestions greatly apprieciated thanks

Dieselbuilder

Try disconnecting the battery's and hold the pos plus neg cables together to drain any remaining voltage wait then hook them back up to see if code clears and if it comes back again it could be a computer glitch if not may be ECM

DCH24V02

got the chance to try that and still it didn't help any still same issue.. It's starting to drive me crazy. Already wasted half the summer and haven't even been able to take the camp trailer anywhere.