I have an 09 Isuzu npr with the 5.2L. 186k miles. I’m having issues with the truck throwing the code p0045, turbo boost control circuit open. Here’s a list of things I have replaced but the code still remains. It comes on instantly even with the truck not running after you delete it. New turbo, turbo control module, boost pressure sensor, maf sensor, ecm, and new batteries. Code still remains. Looking for ideas on what else to try. This is the only code the truck has. Puts it in limp mode and won’t go over 30mph. Any help is appreciated.
danthewolf00
Veteran Expediter
Check the grounds and all the connections to fuses.
The wiring between the ecm and VGT controller need to be checked, perhaps load tested. There should be power, ground, and CAN to the VGT.