dpacella Posted May 28, 2017 Share Posted May 28, 2017 I have a 2007 Mack Aset AC427 engine I'm having issues with. I'm using Mack's PTT software that is installed on my laptop. I have blink code 4-5 (low voltage) popping up (VGT position sensor) and also it wont allow me to calibrate the turbo either. It says "Value outside permitted range" when trying to calibrate. I went into my MacK Diagnostic manual and followed all the different steps for the blink code 4-5. I went to the require pins and check ohms and voltage, I'm getting .01 volts off the harness going to the position sensor connector and also off the ECM pin that goes to the VGT position sensor. I cleaned the grounds on the main engine harness. I have two different ECM's laying around that I swap in and out . I used a different VGT control valve. Just now I replaced the complete engine harness and the blink code 4-5 is still coming up. I have two VGT position sensors laying around that I tried as well. I verified that air is coming out of the VGT control valve and ran air through the steel air line too, but I didn't gauge the air coming out of VGT control valve going to the VGT actuator. I have no major air leaks, I do have the ATC & ABS light intermitting coming on. I used Macks' PTT software, Mack's shop manual and my imagination. I'm not sure what else to try besides it might be the actuator on the turbo? If anyone can point me in the right direction I would appreciate it, thank you. Quote Link to comment Share on other sites More sharing options...
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.