What is P0641 code and How to fix it. Thnx

Question

2007 Chevrolet Uplander - engine code came up while I'm driving and it says on my dashboard , reduce engine power.I checked it on my portable OBD code tester and says P0641. Any knowledge of this code and inexpensive way to fix. Thanks

Answer 1

P0641  5 volt refference 1 circuit 

The ECM has 2 internal 5 volt reference,these are called buses, which supplies 5 volts to various sensor on each buses.A fault condition will affect other 5 volt reference connected to the bus. For circuit 1 buses they are MAP,FTF(fuel tank pressure sensor),APP 2 sensor (acclerator pedal position) EOP (engine oil pressure) sensor,CMP (cansmshaft postion sensor), A/C (aircondition refigerent pressure sensor)  What set this code is 5 volt out of tolerance. The best and first of any repair is to check for poor connection or even corrosion this may even fix the condition. Disconnect the harness of the ECM. inspect it for corrosion clean if neccessary and reconnect.