Glow Plug Malfunction PO380

[lnesomdove]

I have a 1997 3500 Diesel that the SES light has started coming on intermittently. I connected my code reader and it was throwing a PO380 which it interprets as a Glow Plug malfunction A Circuit.

 

Looking through my diesel repair book for Chevy's, the diagnostic to test the glow plugs is to use an ohm meter and check the resistance. All 8 read between 1 and 2: 1.0 to 1.8, which the book says is acceptable.

 

The book also indicates that the glow plugs are now controlled by the computer, so that rules out the glow plug controller, unless it's the computer. What else do I need to check?

[GM-Tech]

I can give you a PDF of the P0380 diagnostic process. It may be difficult to follow each step if your scanner is not capable of reading out some of the values they want you to look at.

 

Interested?